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Cisco IOS Software Releases 12.3 T

Trunk-Management Features

Table Of Contents

Trunk-Management Features

Contents

Information About Trunk Management

Simulated Lines and Trunks

Trunk Conditioning

Congestion Monitoring and Management Features

T1/E1 Alarm Conditioning Feature

PSTN Fallback Feature

Busyout Features

Call Admission Control Features

Analog DID Feature

Analog Centralized Automatic Message Accounting E911 Trunk Feature

How to Configure Trunk Conditioning and Connections

Prerequisites for Configuring Trunk Conditioning and Connections

Configuring Trunk Conditioning

Configuring Trunk-Conditioning Signaling Attributes

Assigning Trunk-Conditioning Attributes to Network Dial Peers

Assigning Voice Classes to Voice Ports

Verifying Signaling Attributes and Trunk Conditioning

Configuring T1/E1 Alarm Conditioning

Assigning Alarm-Generation Parameters

Verifying Alarm-Generation Parameters

Configuring Trunk Connections

Configuring PLAR (Switched) Connections

Configuring Trunk and Tie-Line Connections

Configuring PLAR-OPX Connections

Configuration Examples for Trunk Conditioning and Connections

Trunk-Conditioning: Example

PLAR (Switched Calls) Configuration: Example

Permanent Trunks Configuration: Example

How to Configure Trunk Monitoring and Management

Configuring Analog Centralized Automatic Message Accounting E911 Trunk

Configuring CAMA Card for CAMA Signaling

Configuring ANI Mapping

Verifying CAMA Signaling

Troubleshooting Tips

Monitoring and Maintaining Analog CAMA-E911

Configuring Analog DID

Configuring Voice Ports to Support DID

Verifying DID Voice-Port Configuration

Configuring Call Admission Control

Configuring Call Admission Control for H.323 VoIP Gateways

Configuring MGCP VoIP Call Admission Control

Configuring Local and Advanced Voice Busyout

Configuring the Busyout Trigger Event

Configuring a Voice Port to Busy Out

Configuring a Voice Port to Monitor the Link to a Remote Interface

Configuring a Busyout-Monitoring Voice Class

Configuring a Graceful Busyout

Configuring Busyout Monitor

Configuring Busyout Monitor Gatekeeper

Verifying Busyout Status

Configuring PSTN Fallback

Configuring Fallback to Alternate Dial Peers

Configuring Destination Monitoring without Fallback to Alternate Dial Peers

Configuring Call-Fallback Cache Parameters

Configuring Call-Fallback Jitter-Probe Parameters

Configuring Call-Fallback Probe-Timeout and Weight Parameters

Configuring Call-Fallback Threshold Parameters

Configuring Call-Fallback Wait-Timeout

Configuring VoIP Alternate Path Fallback SNMP Trap

DETAILED STEPS

What to Do Next

Configuring Call-Fallback Map Parameters

Verifying PSTN Fallback Configuration

Monitoring and Maintaining PSTN Fallback

Configuration Examples for Trunk Monitoring and Management

Analog Centralized Automatic Message Accounting E911 Trunk: Examples

Busyout: Examples

Local Voice Busyout Configuration: Examples

Alarm Trigger for Busyout of Voice Ports Configuration: Example

Call Admission Control: Examples

Call Admission Control for H.323 VoIP Gateways: Examples

MGCP VoIP Call Admission Control: Examples

PSTN Fallback: Examples

Additional References

Related Documents

MIBs

Technical Assistance


Trunk-Management Features


This document describes how to condition and connect trunks and how to configure the following trunk-management features:

Analog Centralized Automatic Message Accounting E911 Trunk

Analog DID (Direct Inward Dial)

Busyout features:

Busyout Monitor

Local and Advanced Voice Busyout

Call admission control (CAC) features:

Call Admission Control for H.323 VoIP Gateways

MGCP VoIP Call Admission Control

PSTN Fallback

T1/E1 Alarm Conditioning

Trunk Conditioning

Feature History for Analog Centralized Automatic Message Accounting E911 Trunk

Release
Modification

12.2(11)T

This feature was introduced on the Cisco 2600 series, Cisco 3600 series, and Cisco 3700 series.


Feature History for Analog DID (Direct Inward Dial)

Release
Modification

12.1(5)XM

This feature was introduced on the Cisco 2600 series and Cisco 3600 series.

12.2(2)T

This feature was integrated into this release.


Feature History for Busyout Monitor

Release
Modification

12.0(3)T

This feature was introduced on the Cisco MC3810.

12.0(5)XK

This feature was implemented on the Cisco 2600 series and Cisco 3600 series.

12.0(7)T

This feature was integrated into this release.


Feature History for CAC Features (Call Admission Control for H.323 VoIP Gateways and MGCP VoIP Call Admission Control

Release
Modification

12.1(5)XM

This feature was introduced on the Cisco AS5300, Cisco AS5400, and Cisco AS5800.

12.2(2)T

This feature was integrated into this release.


Feature History for Local and Advanced Voice Busyout

Release
Modification

12.2(13)T

This feature was introduced on the Cisco 200, Cisco 2600 series, Cisco 3600 series, and Cisco 3725.

12.4(2)XA

This feature was enhanced on the Cisco 2600 series and Cisco 3600 series to include support for the busyout monitor gatekeeper command under the voice class busyout mode.

12.4(6)T

The busyout monitor gatekeeper command feature was integrated into this release.


Feature History for PSTN Fallback

Release
Modification

12.1(3)T

This feature was introduced on the Cisco 2600 series, Cisco 3600 series, and Cisco MC3810.

12.2(2)XA

The call fallback and call fallback reject-cause-code commands were introduced.

12.2(4)T

This feature was implemented on the Cisco 7200 series and Cisco 7500 series.

12.3(14)T

The VoIP Alternate Path Fallback SNMP Trap feature was added to the PSTN Fallback feature.


Feature History for T1/E1 Alarm Conditioning

Release
Modification

12.1(3)T

This feature was introduced on the Cisco 2600 series, Cisco 3600 series, and Cisco MC3810.


Feature History for Trunk Conditioning

Release
Modification

12.0(3)XG

This feature was introduced on the Cisco MC3810.

12.0(4)T

This feature was integrated into this release.


Finding Support Information for Platforms and Cisco IOS Software Images

Use Cisco Feature Navigator to find information about platform support and Cisco IOS and CatOS software image support. Access Cisco Feature Navigator at http://www.cisco.com/go/fn.


Note For more information about this and related Cisco IOS voice features, see the entire Cisco IOS Voice Configuration Library—including library preface and glossary, other feature documents, and troubleshooting documentation—at http://www.cisco.com/en/US/products/ps6441/prod_configuration_guide09186a0080565f8a.html.


Contents

Information About Trunk Management

How to Configure Trunk Conditioning and Connections

Configuration Examples for Trunk Conditioning and Connections

How to Configure Trunk Monitoring and Management

Configuration Examples for Trunk Monitoring and Management

Additional References

Information About Trunk Management

A trunk is a communication line between two switching systems—in this case, the switching equipment in a central office (CO) and a PBX. It is a physical and logical point-to-point connection with a permanent wire over which network traffic travels. A backbone is composed of a number of trunks.

VoIP simulates trunk connections between PBXs that are connected to Cisco routers or access servers on each side of the network.

In Figure 1, two PBXs connect to a router using a simulated trunk and a recEive and transMit (E&M) voice port. In this case, a permanent, nonswitched connection transparently connects the two PBXs.

Figure 1 Simulated Trunk Connection

Simulated Lines and Trunks

Simulated lines and trunks enable a telephone user at one location to dial an access code to access a PBX at another location. The user hears a second dial tone from the remote PBX. You can configure two types of simulated connection—switched and permanent—for both analog and digital systems. The connection command creates these connections.

The connection trunk command creates a permanent call that is connected as soon as the routers on each end are booted (see Figure 2). Permanent calls pass limited telephony signaling and operate without collecting digits or requiring changes to the overall dial plan.

Figure 2 Connection Trunk Configuration

The calls simulate a permanent tie line between two PBXs. Both ends must be configured and have compatible voice-port signaling that is either E&M to E&M or foreign exchange office (FXO) to foreign exchange station (FXS). The signaling cannot be FXO to ground-start.

When a switched call is configured (see Figure 3), the user can make a call without dialing any digits. Telephony signaling, such as hookflash, is not passed. If the remote telephone does not answer and digits from an attached telephony device are not collected, the call does not roll over to voice mail.

Figure 3 Connection Private-Line Auto Ringback (PLAR) Configuration

The switched-call configuration works with any type of voice port (E&M, FXO, or FXS) and without any effect on an existing dial plan. It is commonly used to connect PBXs in which the remote devices appear to be physical extensions. The PBX, rather than the router, provides dial tone to the extensions.

The connection tie-line command creates a switched call between two stations or PBXs, and this call bypasses the switch. The connection plar-opx command creates a call that is similar to a switched call. The connection does not take place between the PBX and the local router until the far-end FXS device answers. This enables the PBX to provide centralized voice mail or attendant services when the remote device does not answer.

Trunk Conditioning

The Trunk Conditioning feature enables you to create a voice class, configure specific signaling attributes to the voice class, and then map the attributes in the voice class to either a Voice over Frame Relay, Voice over ATM, or a Voice over HDLC dial peer. Using the voice class, you can define the keepalive-signaling packet interval and the signal pattern (ABCD) bit pattern for Cisco-trunk (private-line) calls.

Trunk-conditioning signaling attributes apply to permanent point-to-point voice connections (private lines and tie lines) that you create using the connection trunk command.

Trunk conditioning enables control over Cisco private-line calls that are sent over Frame Relay or ATM networks. When private-line or tie-line calls are sent between two PBXs, fault indications are sent to the sending PBX. If the call fails, the PBX can select an alternate path to route the calls. Selecting an alternate path applies to analog connections or digital T1/E1 using channel-associated signaling (CAS) ABCD signaling. It does not apply to common-channel signaling (CCS).

When T1/E1 CAS is carried in transparent pass-through mode for arbitrary, unknown, or unsupported CAS protocols, you must define on-hook/idle patterns so that the digital signal processor (DSP) code can sense the idle call state and shut off the flow of voice packets when no active call is in progress. This mode provides an additional idle bandwidth-saving mechanism for those cases when Voice Activity Detection (VAD) is not desired.


Note Cisco MC3810 series concentrators support additional trunk-conditioning features that specify timing, signaling, and transmission options. The features provide enhanced control over call rerouting in cases of trunk failure and increased bandwidth availability due to suppression of voice packets on out-of-service (OOS) trunks.


Congestion Monitoring and Management Features

Congestion monitoring of permanent and switched calls is performed with the following features:

T1/E1 alarm conditioning

PSTN fallback

Busyout functionality including busyout monitoring, CAC, Analog DID, and analog centralized automatic message accounting E911 trunk.

These features provides the following capabilities:

Signaling and suppression of voice traffic for idle or OOS network trunks

Busyout of the ports interfacing with a local PBX

Graceful refusal of calls by gateways when resources are unavailable

Direct dialing to an extension on a PBX without the assistance of an operator or automated call attendant

Sending of the calling number to each switching point via Centralized Automatic Message Accounting (CAMA)

An OOS condition can be signaled using an ABCD bit pattern that is different from the busy or seized state. The difference enables the PBX to differentiate between OOS and congestion.

T1/E1 Alarm Conditioning Feature

The T1/E1 Alarm Conditioning feature provides status monitoring on T1/E1 PBX voice interfaces for simulated lines and trunks that you create using the connection command. It supports operation with CAS but not with CCS.

A T1/E1 alarm can be triggered by events detected through the monitoring of a specified set of voice ports within a T1/E1 trunk. A monitored set includes a defined voice port that has a specified DS0 group or groups and configured for one of the following:

End-to-end connection of permanent virtual circuits (PVCs)

Busyout of switched virtual circuits (SVCs), where busyout is initiated by means of the busyout monitor command

When all monitored voice ports on a T1/E1 trunk are OOS (PVCs are OOS and SVCs are busied out), a T1/E1 alarm indication signal (AIS) is generated on the T1/E1 trunk that connects to the PBX or PSTN.


Note Voice ports that are busied out by the busyout forced command do not trigger a T1/E1 alarm.


PSTN Fallback Feature

The PSTN Fallback feature monitors congestion in the IP network and redirects calls to the PSTN or rejects calls based on network congestion. You define congestion thresholds based on your configured network. This feature can reroute calls to an alternate IP destination or, if the IP network is found unsuitable for voice traffic during periods of network congestion, to the PSTN. This enables a service provider to give a reasonable guarantee about conversation quality to its VoIP users at the time of call admission.


Note For information on VoIP, ATM, Calculated Planning Impairment Factor (ICPIF), and Service Assurance Agent (SAA), see the "Related Documents" section.



Note PSTN fallback does not ensure that a VoIP call is protected from the effects of congestion. This is the function of other quality-of-service (QoS) mechanisms such as IP Real-Time Transport Protocol (RTP) priority and low-latency queueing (LLQ).


PSTN fallback includes the following capabilities:

Offers flexibility to define the congestion thresholds based on the network by defining the following thresholds:

A threshold based on ICPIF, which is derived as part of ITU G.113, including the following: G.729, G.711, G.723, G.726, GSM, and G.728

A threshold based solely on packet delay and loss measurements

Uses SAA probes to provide packet delay, jitter, and loss information for the relevant IP addresses. Based on the packet loss, delay, and jitter encountered by these probes, an ICPIF or delay/loss value is calculated. For more information, see the "Service Assurance Agent" section.

Supports calls of any codec specified in G.113, including the following: G.729, G.711, G.723, G.726, GSM, and G.728.

The fallback subsystem has a network-traffic cache that maintains the ICPIF or delay/loss values for various destinations. The subsystem helps performance, because new calls to a well-known destination do not have to wait on a probe. The value is usually cached from a previous call.

Once the ICPIF or delay/loss values are calculated and stored, they remain until the cache ages out or overflows. Until a value ages out, probes are sent periodically for that destination. The time interval is user configurable.

The following is an example of the PSTN fallback sequence. In the example, call fallback active is enabled and an ICPIF threshold is defined. Call control would be similar if loss and delay thresholds were defined.

1. A call comes into the router. The IP address of the destination is checked against the configured maps to see if it should be sent to another router, such as a backhaul router, or to an alternate dial peer. If it should be sent to another router, the IP address for the fallback subsystem is replaced with the target router. If it should be sent to an alternate dial peer, the router matches that dial peer and obtains the destination information (codec, IP address, and so on).


Note The change is made in the destination address of the probing address. The destination for the actual call is not changed.


2. The router calls the fallback subsystem to look up the specified destination in its network traffic cache. If the ICPIF value exists and is current, then the router uses that value to decide whether to permit the call into the VoIP network. If the router determines that the network congestion is below the configured threshold (by looking at the value from the probe or a cached value), then the call is connected. Otherwise, the router checks the next dial-peer match again in the same way. Eventually, if all the VoIP dial peers are deemed unsuitable, then the call is hairpinned to the PSTN by virtue of a configured POTS dial peer (for analog or digital interfaces). If no PSTN dial peer is present, a fast-busy is sent to the PBX (in case of digital interfaces).


Note It is not possible to signal a fast-busy to some interfaces.


3. The fallback subsystem continues probing in the background periodically (period time is configured by the call fallback probe-timeout command), so that the network congestion information is available when there is a call request. The first call for a particular dial peer may be delayed while the router calculates the congestion information for that destination.

If the timeout threshold is set and the router has not received calls for a particular destination after the threshold expires, the router removes that destination's traffic information from the cache.


Caution Configuring call fallback active in a gateway creates an SAA jitter probe against other (target) gateways to which the calls are sent. In order for the call fallback active to work properly, the target gateways must have the rtr responder command (in Cisco IOS releases prior to 12.3(14)T) or the ip sla monitor responder command (in Cisco IOS Release 12.3(14)T or later) in their configurations. If one of these commands is not included in the configuration of each target gateway, calls to the target gateway will fail.

Calculated Impairment Planning Factor

ICPIF calculates an impairment factor for every piece of equipment along the voice path and adds the values to get the total impairment. The ITU assigns the different types of impairments, such as noise, delay, and echo. The threshold is based on ICPIF, which is derived as part of ITU G.113 including the following: G.729, G.711, G.723, G.726, GSM, and G.728.

The ICPIF handling has been introduced for compatibility with H.323. Part of ICPIF includes a concept of Total Impairment Value that is a function of loss of packets, delay of packets, and codecs used based on the round-trip reports from SAA.

Service Assurance Agent

SAA is a network-congestion analysis mechanism. SAA provides delay, jitter, and packet-loss information for configured IP addresses. SAA is based on a client-server protocol defined on UDP. It has an Message Digest 5 (MD5), which is a message authentication algorithm in SNMP v.2. MD5 verifies the integrity of the communication, authenticates the origin, and checks for timeliness.

SAA uses the UDP port (port 1976) for sending the SAA control message to the terminating gateway. SAA probe packets go out on randomly selected ports from the top end of the audio UDP port range (16384 to 32767).

The port pair (RTP and Real-Time Transport Control Protocol [RTCP] port) is selected, and by default SAA for call fallback uses the RTCP port (odd number) to avoid going into the priority queue, if enabled. If fallback is configured to use the priority queue, the RTP port (even number) is selected. The audio UDP port range must be included in the priority queue for fallback priority queueing to work.

Busyout Features

This section describes the following busyout features:

Local Voice Busyout Feature

Advanced Voice Busyout Feature

Busyout Monitor Feature

Local Voice Busyout Feature

The Local Voice Busyout feature busies out trunks that are assigned to PVCs so that the PBX does not seize the circuit. It enables the PBX to route a call based on the actual availability of trunks. Local voice busyout enables the following:

A group of voice ports to be marked busy if a link is broken.

Specific voice ports in a PVC application to be marked busy under specified conditions.

When ports are marked busy, a call is forced back to the originating equipment (typically a PBX) that reroutes the call over an alternate path. This action ensures that a caller does not experience "dead air" resulting from a connection that never terminates.

The feature provides a way to busy out a voice port if a monitored network interface changes state. When a monitored interface changes to a specified state—to OOS or in-service—the voice port presents a seized/busyout condition to the attached PBX or other customer premises equipment (CPE). The PBX or other CPE can then attempt to select an alternate route.

This feature differs from busy-back. Busy-back refers to the signal sent from within the network to the calling party that indicates a busy (or congested) state anywhere along the route, up to and including the condition of the called party.


Note The Local Voice Busyout feature is supported on analog and digital voice ports using CAS, but not on Cisco MC3810 BRI voice modules.


Advanced Voice Busyout Feature

The Advanced Voice Busyout feature adds the following functionality to the local voice busyout feature:

For VoIP, monitoring of links to remote, IP-addressable interfaces by use of service assurance agent (SAA)

Configuration by voice class to simplify and speed up the configuration of voice busyout on multiple voice ports (or n DS-0/PRI groups on universal gateway platforms).

This feature enables you to do the following:

Configure individual voice ports to enter the busyout state if an SAA probe signal returned from a remote, IP-addressable interface detects loss of IP connectivity by crossing a specified delay or loss threshold.

Define voice classes with specified busyout conditions, and assign a particular voice class to any number of voice ports.

SAA-probe monitoring of remote interfaces is intended for use with VoIP networks, although it can also be used with Voice over Frame Relay (VoFR) and Voice over ATM (VoATM) networks.

Busyout Monitor Feature

The Busyout Monitor feature is one aspect of call admission control that uses a data network and the PSTN to provide the best possible quality and cost savings for VoIP calls. It also provides the following:

Logical connections between LAN/WAN interfaces of routers in a VoIP gateway with directly connected voice ports

Port-by-port definition

Tracking of any directly connected main interface, subinterface, or virtual interface without monitoring the status of remote devices

Call Admission Control Features

This section describes the following CAC features:

Call Admission Control for H.323 VoIP Gateways Feature

MGCP VoIP Call Admission Control Feature

Call Admission Control for H.323 VoIP Gateways Feature

This feature provides the ability to support resource-based CAC processes. These resources include system resources such as CPU, memory, and call volume, and interface resources such as call volume.

If system resources are not available to admit the call, the result is either a system denial (which busies out all T1 or E1) or per-call denial (which disconnects, hairpins, or plays, a message or tone). If the interface-based resource is not available to admit the call, the call is dropped from the session protocol (such as H.323).

PSTN Fallback offers CAC based on congestion thresholds in H.323 networks.


Note For information on H.323, see the"Related Documents" section.


User-Selected CAC Commands

The feature allows you to configure thresholds for local resources and memory and CPU resources.


Note For a list of local resources that are configured by the call threshold poll-interval command for call admission, see the command-reference document listed in the "Related Documents" section.


With the call threshold command, you can configure two thresholds, high and low, for each resource. Call treatment is triggered when the current value of a resource exceeds the configured high. The call treatment remains in effect until the current resource value falls below the configured low. Having high and low thresholds prevents call admission flapping and provides hysteresis in call admission decision making.

With the call spike command, you can configure the limit for incoming calls during a specified time period. A call spike is the term for when a large number of incoming calls arrive from the PSTN in a very short period of time (for example, 100 incoming calls in 10 ms).

With the call treatment command, you can select how the call should be treated when local resources are not available to handle the call. For example, when the current resource value for any one of the configured triggers for call threshold has exceeded the configured threshold, the call treatment choices are as follows:

Time-division multiplexing (TDM) hairpinning—Hairpins the calls through the POTS dial peer.

Reject—Disconnects the call.

Play message or tone—Plays a configured message or tone to the user.

Resource-Unavailable Signaling

The Resource Unavailable Signaling feature supports the autobusyout feature where channels are busied out when local resources are not available to handle the call. Autobusyout is supported on both CAS and PRI channels:

CAS—Uses busyout to signal that local resources are unavailable.

PRI—Uses either service messages or a cause code to signal that resources are unavailable.

MGCP VoIP Call Admission Control Feature

The MGCP VoIP Call Admission Control feature enables certain Cisco CAC capabilities on VoIP networks that are managed by Media Gateway Control Protocol (MGCP) call agents. These capabilities permit the gateway to identify and gracefully refuse calls that are susceptible to poor voice quality.

Poor voice quality on an MGCP voice network can result from transmission artifacts such as echo, from the use of low quality codecs, from network congestion and delay, or from overloaded gateways. The first two causes can be overcome by using echo cancellation and better codec selection. The last two causes are addressed by MGCP VoIP CAC.

Before the release of MGCP VoIP CAC, MGCP voice calls were often established regardless of the availability of resources for those calls in the gateway and the network. MGCP VoIP CAC ensures resource availability by disallowing calls when gateway and network resources are below configured thresholds and by reserving guaranteed bandwidth throughout the network for each completed call.

MGCP VoIP CAC has three components for improving voice quality and reliability (see Table 48).

Table 48 MGCP VoIP CAC Components

Component
Purpose
Supported Platforms

System Resource Check (SRC) CAC

Evaluates memory and call resources local to the gateway

MGCP 1.0

MGCP 0.1

Resource Reservation Protocol (RSVP) CAC

Surveys bandwidth availability on the network

MGCP 1.0

MGCP 0.1

Cisco Service Assurance Agent (SA Agent)1 CAC

Appraises network congestion conditions on the network

MGCP 1.0

1 SA Agent was called Response Time Reporter (RTR) in earlier Cisco IOS software releases.


If all three CAC types are configured on a gateway, the gateway checks resources in this order: SRC CAC, then RSVP CAC, then SA Agent CAC. If any resource check fails, the call fails and no further checks are performed. When the call fails, the gateway refuses to accept it.

MGCP VoIP CAC supports several types of calls, depending on platform (Table 49).

Table 49 MGCP VoIP CAC Call Types by Platform 

Call Type
Cisco Platform
IAD2420
2600 series
3620
3640
3660
MC3810

911 calls

Yes

Call-waiting calls

Yes

Yes

Yes

Yes

Yes

CAS PBX calls, both immediate-start and wink-start

Yes

Yes

Yes

Yes

Yes

Yes

Named Signaling Event (NSE)-based audible ringback calls

Yes

Yes

Yes

Yes

Yes

Yes

One-direction voice-path calls

Yes

Yes

Yes

Yes

Yes

Yes

Regular two-way calls

Yes

Yes

Yes

Yes

Yes

Yes

Signaling System 7/ISDN User Part (SS7/ISUP) calls

Yes

Three-way calls

Yes

Yes

Yes

Yes

Yes


Fax/modem pass-through and fax/modem relay are not supported.


NoteMGCP VoIP CAC is not supported on the following profiles of MGCP 1.0: PacketCableTM Network-based Call Signaling (NCS) 1.0 and PacketCableTM Trunking Gateway Control Protocol (TGCP) 1.0.

For information on MGCP, SRC, RSVP, and SA Agent, see the "Related Documents" section.


SRC CAC

When a call agent attempts to set up or modify a call, MGCP SRC CAC measures available local resources on the gateway and compares them to the configured thresholds for those resources. If one or more resources are beyond their thresholds, SRC CAC notifies the call agent of the results and refuses the call. If resources are within bounds and a call is subsequently established, local resources are guaranteed for the duration of the call.

SRC CAC checks these gateway thresholds, as configured by the user:

CPU usage: both finest CPU utilization and average CPU utilization

Memory usage, including I/O memory, process memory, and total memory

Total calls allowed on the gateway

If several types of thresholds are configured on the gateway, the gateway checks them in sequence to determine if sufficient resources are available to continue setting up the call.


Note Network access server data calls are not counted by SRC in the total call calculations.


When the gateway sends an unavailable condition to the call agent, the call agent takes responsibility for the type of treatment to attach to the call attempt. The call agent may choose to handle such situations by rerouting the call, playing an announcement that the call cannot be completed, playing special tones, or sending the call back to take a different path. Once resources become available again, the gateway resumes the acceptance of new calls.

RSVP CAC

MGCP RSVP CAC determines if sufficient bandwidth exists across the IP network to accept a call and refuses the call if end-to-end bandwidth is not available.

To accept a call, MGCP RSVP CAC checks for and reserves the network bandwidth between the originating gateway and the terminating gateway before attempting to complete the call. If sufficient bandwidth is not available or cannot be reserved, the gateway alerts the call agent to this condition and the call agent applies a previously configured treatment to the refused call (plays an announcement or special tones, or sends the call back to take a different path).

RSVP is an out-of-band, end-to-end signaling protocol that requests a certain amount of bandwidth and latency with each network hop that supports RSVP. If a network node (router) does not support RSVP, RSVP moves on to the next hop. A network node has the option to approve or deny the reservation on the basis of the load of the interface to which the service is requested.

A voice call triggers two RSVP reservations because the reservation and admission control mechanisms provided by RSVP are unidirectional. Each voice gateway is responsible for initiating and maintaining one reservation toward the other voice gateway. RSVP CAC for a VoIP call fails if at least one of the reservations fails.

Cisco VoIP CAC applications use RSVP to limit the accepted voice load on the IP network and guarantee the QoS levels of calls. RSVP CAC synchronizes RSVP signaling with the call setup signaling protocol (MGCP, in this case) to ensure that the bandwidth reservation is established in both directions before a call moves to the alerting phase (ringing). This synchronization ensures that the called-party phone rings only after the resources for the call have been reserved. Using RSVP-based admission control, VoIP applications can reserve network bandwidth and react appropriately if bandwidth reservation fails.

SA Agent CAC

Cisco SAA is a Cisco IOS feature that allows users to monitor network performance and congestion between a Cisco router and a remote device, which can be another Cisco router, an IP host, or a multiple virtual storage (MVS) host. Performance can be measured for real-world scenarios through the configuration of SA Agent operations that are executed periodically. Performance metrics include round-trip response time, connect time, packet loss, application performance, and interpacket delay variance (jitter). The SA Agent feature allows users to receive notifications and perform troubleshooting and problem analysis on the basis of the statistics collected by the SA Agent.

SA Agent probes traverse the network to a given IP destination and measure the loss and delay characteristics of the network along the path traveled. These values are returned to the outgoing gateway to use in making a decision on the condition of the network and its ability to carry a voice call. SA Agent probes do not provide any bandwidth information, either configured or available. However, if bandwidth across a link anywhere in the path that the voice call will follow is oversubscribed, it is reasonable to assume that the packet delay and loss values returned by the probe will indeed reflect this condition, even if indirectly. The SA Agent protocol is a client/server protocol defined in User Datagram Protocol (UDP). The client builds and sends the probe, and the server (previously the RTR Responder) returns the probe to the sender.

SA Agent probe delay and loss information is used in calculating a single value that can be used as a gauge of network impairment and as a threshold for CAC decisions.

Analog DID Feature

The Analog Direct Inward Dialing (DID) feature is a service offered by telephone companies that enables callers to dial directly to an extension on a PBX without the assistance of an operator or automated call attendant. It makes use of DID trunks, which forward only the last three to five digits of a phone number to the PBX. If, for example, a company has a PBX with extensions 555-1000 to 555-1999, and a caller dials 555-1234, the local CO would forward 234 to the PBX. The PBX would then ring extension 234. This entire process is transparent to the caller.

When this feature is configured, a voice-enabled router equipped with an analog DID interface can receive calls from a DID trunk and connect them to the appropriate extensions. The DID state machine is identical to the E&M state machine and uses one of the following signaling types:

Immediate-start—The originating end seizes the line by going off hook and, without waiting for a response, it begins to outpulse digits. The address signaling used with immediate-start signaling consists only of dial-pulsing.

Wink-start—The originating end seizes the line by going off-hook. It waits for acknowledgment from the other end before outpulsing digits. This serves as an integrity check that identifies a malfunctioning trunk and allow the network to send a re-order tone to the calling party.

Delay dial—The originating end seizes the line and waits 200 ms to determine if the far end is on-hook. If so, the originating end then outpulses digits. If the far end is off-hook, the originating end waits until the far end is on-hook before outpulsing digits.

Figure 4 shows a hypothetical topology where a user connected to the PSTN (Caller A) dials various numbers and is connected to the appropriate extensions on a PBX.

Figure 4 DID Support

Number Dialed by User A
Number Received by Router
Extension Receiving Call

555-1234

234

User C

555-1345

345

User D

555-1456

456

User B

555-1678

678

No dial-peer match found; fast busy tone is played.



Note For information on installing and configuring Cisco 2600 series and Cisco 3600 series, on voice configuration, and on IP, Frame Relay, and ATM, see the "Related Documents" section.


Analog Centralized Automatic Message Accounting E911 Trunk Feature

Because E911 calls require special routing, the North American emergency E911 phone system is built largely outside of the normal PSTN on which common voice traffic rides. Calls to emergency services are routed based on the calling number, not the called number. The calling number is checked against a database of emergency service providers that cross-references the providers for the caller's particular location. The call is then routed to the proper public-service answering point (PSAP), which, in turn, dispatches those services for the caller's location.

During setup of a call to E911, before the audio channel is connected, the calling number is sent to each switching point (known as a Selective Router [SR]) via an old telephony protocol known as CAMA. CAMA was originally designed as a protocol for long-distance billing, because it provides for carrying both calling and called number using in-band signaling. CAMA allows the telephone system to send a station identification number to the PSAP via multifrequency (MF) signaling through the telephone company's E911 equipment. CAMA trunks are used in 80 percent of E911 networks.

The calling number is needed at the PSAP for two reasons:

To use the calling number to reference the Automatic Location Identification (ALI) database to find the caller's exact location and any other information about the caller that may have been stored in the database.

To have the callback number in case the call is disconnected.

Figure 5 illustrates the topography in existing E911 networks. Figure 6 illustrates an E911 network using the VIC-2CAMA card with Cisco 2600 series or Cisco 3600 series routers.

Figure 5 Existing E911 Networks

Figure 6 Analog CAMA E911 Networks

How to Configure Trunk Conditioning and Connections

This section contains the following procedures:

Prerequisites for Configuring Trunk Conditioning and Connections

Configuring Trunk Conditioning

Configuring T1/E1 Alarm Conditioning

Configuring Trunk Connections

Prerequisites for Configuring Trunk Conditioning and Connections


Note For information on the following configuration tasks, see the "Related Documents" section.


Configure the following as appropriate:

VoFR using FRF.11

VoATM

VoIP

Voice ports

Configuring Trunk Conditioning

This section contains the following procedures:

Configuring Trunk-Conditioning Signaling Attributes

Assigning Trunk-Conditioning Attributes to Network Dial Peers

Assigning Voice Classes to Voice Ports

Verifying Signaling Attributes and Trunk Conditioning

Configuring Trunk-Conditioning Signaling Attributes

Different trunk-conditioning signaling attributes may be required to match the characteristics of the different PBXs to which the router connects. For this reason, you configure these attributes by creating a voice class for each set of attributes required. You then configure trunk-conditioning attributes for each voice class and assign the voice class to one or more dial peers. You must configure a voice class and assign it to at least one dial peer before trunk-conditioning signaling attributes take effect.


Note This configuration supports the North America CAS protocol and applies only to Cisco private-line or FRF.11 trunk calls. It does not apply to digital T1/E1 trunks using CCS.


To configure trunk-conditioning signaling attributes, use the following commands.

SUMMARY STEPS

1. voice class permanent tag

2. signal keepalive seconds

3. signal sequence oos {both | idle-only | no-action | oos-only}

4. signal pattern {idle receive | idle transmit | oos receive | oos transmit} bit-pattern

5. signal timing oos timeout {seconds | disabled}

6. signal timing oos restart seconds

7. signal timing oos slave-standby seconds

8. signal timing oos {suppress-all | suppress-voice} seconds

9. signal timing idle suppress-voice seconds

10. exit

DETAILED STEPS

 
Command
Purpose

Step 1 

Router(config)# voice class permanent tag

Enters voice-class configuration mode and creates a voice class. Range: 1 to 10000 (must be unique on the router).

Note This command differs from the voice-class command in dial-peer voice configuration mode, which contains a hyphen.

Step 2 

Router(config-class)# signal keepalive seconds

(Optional) Defines the keepalive signaling packet interval, in seconds. Range: 1 to 65535. Default: 5.

Step 3 

Router(config-class)# signal sequence oos {both 
| idle-only | no-action | oos-only}

(Optional) Sets the signaling pattern (when the far-end keepalive message is lost or when AIS is received from the far end). Keywords are as follows:

both—Restores the default (both signaling patterns are sent). The no form of the command restores the default also.

idle-only or oos-only—Sends only one signaling pattern.

no-action—Sends no signaling pattern.

Step 4 

Router(config-class)# signal pattern 
{idle receive | idle transmit | oos receive | 
oos transmit} bit-pattern

(Optional) Overrides the default values for the idle and receive OOS patterns or configures OOS transmit signaling patterns.

Repeat the command entry for each signal pattern required.

Step 5 

Router(config-class)# signal timing oos timeout 
{seconds | disabled}

(Optional) Changes the timeout period for asserting a receive OOS pattern to the PBX when signaling packets are lost. This action changes the delay time before a busyout is sent to the PBX.

Step 6 

Router(config-class)# signal timing oos restart 
seconds

(Optional) Configures permanent voice connections to be restarted after the trunk has been OOS for a specified time. Default: no signal timing OOS pattern parameters are configured.

Note This command has no effect if the signal timing oos timeout command is set to disabled.

Step 7 

Router(config-class)# signal timing oos 
slave-standby seconds

(Optional) Configures a slave port to return to its initial standby state after the trunk has been OOS for a specified time. Default: no signal timing OOS pattern parameters are configured.

Note This command has no effect if the signal timing oos timeout command is set to disabled.

Step 8 

Router(config-class)# signal timing oos 
{suppress-all | suppress-voice} seconds

(Optional) Configures the router or concentrator to stop sending voice packets or voice and signaling packets to the network if it detects a transmit OOS signaling pattern from the PBX for a specified time. Default: no signal timing OOS pattern parameters are configured.

Note An OOS transmit signaling pattern must be configured with the signal pattern oos transmit command (see Step 4).

Step 9 

Router(config-class)# signal timing idle 
suppress-voice seconds

(Optional) Configures the router or concentrator to stop sending voice packets after the trunk has been idle for a specified time. Default: no signal timing OOS pattern parameters are configured.

Step 10 

Router(config-class)# exit

Exits the current mode.

Assigning Trunk-Conditioning Attributes to Network Dial Peers

After you create a voice class, you must apply it to the dial-peer configuration. You can assign trunk-conditioning attributes to VoIP, VoFR, or VoATM dial peers, but not to POTS dial peers.


Note This feature applies only to Cisco trunk (private-line) or FRF.11 trunk calls and does not apply to digital T1/E1 trunks using CCS.


To apply trunk-conditioning signaling attributes to a network dial peer, use the following commands.

SUMMARY STEPS

1. dial-peer voice tag {pots | vofr | voip}

2. voice-class permanent tag

3. exit

DETAILED STEPS

 
Command
Purpose
 

Router(config)# dial-peer voice tag {pots | vofr | voip}

Enters dial-peer configuration mode for a particular peer.

 

Router(config-dial-peer)# voice-class permanent tag

Assigns the voice class to the dial peer. Range: 1 to 10000 (must be unique on the router).

Note This command differs from the voice class command in global configuration mode, which does not contain a hyphen.

 

Router(config-dial-peer)# exit

Exits the current mode.

Assigning Voice Classes to Voice Ports

To assign a voice class to a voice port, use the following commands.

SUMMARY STEPS

1. voice-port slot/subunit/port

2. voice-class permanent tag

3. exit

DETAILED STEPS

 
Command
Purpose

Step 1 

Router(config)# voice-port slot/subunit/port

Enters voice-port configuration mode for a specified voice port.

Step 2 

Router(config-voiceport)# voice-class permanent 
tag

Assigns the voice class to a voice port. Range: 1 to 10000 (must be unique on the router).

Note This command differs from the voice class command in global configuration mode, which does not contain a hyphen.

Step 3 

Router(config-voiceport)# exit

Exits the current mode.

Verifying Signaling Attributes and Trunk Conditioning


Step 1 show voice trunk-conditioning signaling

Use this command to verify signaling attributes (timing parameters).

The following is sample output for voice-port 1/5 on a Cisco MC3810.

Router# show voice trunk-conditioning signaling 1/5

1/5 :
TX INFO :slow-mode seq#= 25, sig pkt cnt= 42, last-ABCD=0000
hardware-state ACTIVE signal type is NorthamericanCAS
signal path is OPEN
 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
RX INFO :slow-mode, sig pkt cnt= 37
missing = 0, out of seq = 0, very late = 0
playout depth = 0 (ms), refill count = 1
prev-seq#= 25, last-ABCD=0000
trunk_down_timer = 4212 (ms), idle timer = 0 (sec),
tx_oos_timer = 0 (sec), rx_ais_duration = 0 (ms)
forced playout signal pattern = NONE
signaling playout history
0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000 0000 0000

The following is sample summary output for voice ports on a Cisco MC3810:

Router# show voice trunk-conditioning signaling summary

1/1 is shutdown
1/4 is shutdown
1/5 :
TX INFO :slow-mode seq#= 25, sig pkt cnt= 40, last-ABCD=0000
hardware-state ACTIVE signal type is NorthamericanCAS signal path is OPEN
RX INFO :slow-mode, sig pkt cnt= 36, prev-seq#= 25, last-ABCD=0000

Step 2 show voice trunk-conditioning supervisory

Use this command to determine the status of trunk supervision and configuration parameters.

The following is sample output for a Cisco MC3810 multiservice concentrator.

Router# show voice trunk-conditioning supervisory 1/5

1/5 : state : TRUNK_SC_CONNECT, voice : on, signal : on, slave
status: trunk connected
sequence oos : idle and oos
pattern :rx_idle = 0x0 rx_oos = 0xF tx_oos =  0xF
timing : idle = 0, restart = 0, standby = 0, timeout = 40
supp_all = 50, supp_voice = 0, keep_alive = 5
timer: oos_ais_timer = 0, timer = 0

Step 3 show voice call summary

Use this command to show summary call data.

The following is sample output sample is for voice port 1/5 on a Cisco MC3810:

Router# show voice call summary

PORT      CODEC    VAD VTSP STATE            VPM STATE
========= ======== === ===================== ========================
1/1                                          *shutdown*
1/2       -         -  -                     FXSLS_ONHOOK
1/3       -         -  -                     FXSLS_ONHOOK
1/4                                          *shutdown*
1/5       g729r8    n  S_CONNECT             S_TRUNKED
1/6       -         -  -                     EM_ONHOOK

Step 4 show running-configuration

Use this command to verify signaling and timing parameters. The trunks do not have to be connected and active.

The following is sample output for voice-ports 0:0, 0:1, and 0:2 on a Cisco MC3810.

Router# show running-configuration

Building configuration...

Current configuration:
.
.
.
voice class permanent 100
signal timing idle suppress-voice 2000
signal timing oos restart 1000
.
.
.
voice-port 0:0
 voice-class permanent 100
 compand-type a-law
!
voice-port 0:1
 voice-class permanent 100
 compand-type a-law
!
voice-port 0:2
 voice-class permanent 100
 compand-type a-law
.
.
.


Configuring T1/E1 Alarm Conditioning

This section contains the following procedures:

Assigning Alarm-Generation Parameters

Verifying Alarm-Generation Parameters

You can configure a network to monitor any combination of DS0 groups on a T1 or E1 trunk. An alarm is triggered only if all of the monitored DS0 groups on a T1 or E1 trunk are OOS. If one monitored DS0 group is in service, no alarm is triggered. DS0 groups can be either of the following types:

DS0 groups configured as voice ports for permanent point-to-point voice connections created using the connection command (for private lines and tie lines). These DS0 groups can go OOS due to a trunk-conditioning event or busyout event (except forced busyout).

DS0 groups configured as voice ports for switched voice traffic using CAS. These DS0 groups can go OOS, because of a busyout event (except forced busyout).


Note Alarm conditioning is not supported on CCS trunks.


Prerequisites


Note For information on the following configuration tasks, see the "Related Documents" section.


Configure VoFR or VoATM, including POTS and network dial peers.

Configure voice ports, including busyout and trunk conditioning.

Configure DS0 groups.

Assigning Alarm-Generation Parameters

To assign alarm-generation parameters, use the following commands.

SUMMARY STEPS

1. controller {t1 | e1} {0 | 1}

2. mode {cas | atm}

3. ds0-group ds0-group-no timeslots timeslot-list type {e&m-immediate | e&m-delay | e&m-wink | fxs-ground-start | fxs-loop-start | fxo-ground-start | fxp-loop-start}

4. alarm-trigger blue ds0-group-list

5. exit

DETAILED STEPS

 
Command
Purpose

Step 1 

Router(config)# controller {t1 | e1} {0 | 1}

Enters controller configuration mode.

Step 2 

Router(config-controller)# mode {cas | atm}

Configures the controller for CAS.

Step 3 

Router(config-controller)# ds0-group ds0-group-no timeslots timeslot-list type {e&m-immediate | e&m-delay | e&m-wink | fxs-ground-start | fxs-loop-start | fxo-ground-start | fxp-loop-start}

Configures DS0 groups on the controller. Keywords and arguments vary according to the platform and type of trunk.

Repeat for each DS0 group to be configured.

Step 4 

Router(config-controller)# alarm-trigger blue ds0-group-list

Enables alarm conditioning and configures the system to monitor one or more DS0 groups. Keyword and argument are as follows:

blue—An AIS alarm; required.

ds0-group-list—A single DS0 group number, a single range of numbers, or multiple ranges of numbers separated by commas. Range: for T1, 0 to 23; for E1, 0 to 30.

Step 5 

Router(config-controller)# exit

Exits the current mode.

Verifying Alarm-Generation Parameters


Step 1 show running-configuration

Use this command to verify that the T1/E1 controller is correctly configured for generating alarms.

The following is sample output for a Cisco MC3810 with controller E1 0 configured so that a blue alarm is generated if DS0 groups 0, 1, and 2 (voice ports 0:0, 0:1, and 0:2) are all busied out:

Router# show running-configuration

Building configuration...
.
controller E1 0
 mode cas
 ds0-group 0 timeslots 1-10 type e&m-immediate-start
 ds0-group 1 timeslots 11-15,17-20 type e&m-immediate-start
 ds0-group 2 timeslots 21-30 type e&m-immediate-start
 alarm-trigger blue 0-2

Step 2 Create an OOS state on all voice ports on the controller (this should cause a blue alarm to be generated).

For voice ports with the busyout monitor function enabled (switched or trunked), busy out the voice ports as follows:

a. Shut down or disconnect any serial and Ethernet interfaces that are monitored for OOS busyout.

b. Activate any serial and Ethernet interfaces that are monitored for in-service busyout.


Note All the configured voice ports for switched connections and monitored for alarm trigger must have the busyout monitor function enabled; otherwise, no alarm can be triggered.


For voice ports with the busyout monitor function disabled (trunked only), create an OOS condition on the trunks by shutting down or disconnecting the associated local serial interface, or by shutting down the associated far-end T1/E1 controller.

Step 3 show controller

Use this command to display alarm status.

The following sample output displays the alarm status of the T1 or E1 trunk on a Cisco MC3810. A yellow alarm is received and detected, and a blue alarm is generated and transmitted:

Router# show controller t1 0

T1 0 is up.
  Applique type is Channelized T1
  Cablelength is long gain36 0db
  Yellow alarm detected.
  alarm-trigger is set to Blue
  Alarm is triggered
  Slot 3 CSU Serial #00000056 Model TEB HWVersion 3.70 RX level = 0DB
  Framing is ESF, Line Code is B8ZS, Clock Source is Line.
  Data in current interval (827 seconds elapsed):


Configuring Trunk Connections

This section contains the following procedures:

Configuring PLAR (Switched) Connections

Configuring Trunk and Tie-Line Connections

Configuring PLAR-OPX Connections

Configuring PLAR (Switched) Connections

PLARs (switched) connections enable the user to make a call without dialing any digits. The router uses the digits that follow the command internally to send the call to a dial peer.

To configure a PLAR connection, use the following command in voice-port configuration mode.


Note The syntax of the voice-port command is hardware specific, as described in the Cisco IOS command references listed in the "Related Documents" section.


To configure PLAR connections, use the following commands.

SUMMARY STEP

1. voice-port slot/subunit/port

2. connection plar string

3. exit

DETAILED STEP

 
Command
Purpose

Step 1 

Router(config)# voice-port slot/subunit/port

Enters voice-port configuration mode for a specified voice port.

Step 2 

Router(config-voiceport)# connection plar string

Specifies a PLAR connection and associates a peer directly with an interface. The string argument is a destination telephone number. Valid entries are any series of digits that specify the E.164 standard.

Step 3 

Router(config-voiceport)# exit

Exits the current mode.

Configuring Trunk and Tie-Line Connections

Trunk and tie-line connections are virtual connections to PBXs. They are dedicated until disabled.

Restrictions

Trunk/tie-line connections are applicable only to Cisco 2600 series and Cisco 3600 series.

You must use the following voice-port combinations:

E&M to E&M (same type)

FXS to FXO

FXS to FXS (without signaling)

You can not perform number expansion on the destination pattern telephone numbers configured for trunk connection.

You must configure both end routers to establish a trunk connection.

You must use the shutdown/no shutdown command sequence on the voice port to activate the configuration.

SUMMARY STEPS

1. dial-peer voice tag pots

2. destination-pattern [+]string [T]

3. port {slot/subunit/port} | {slot/port:ds0-group-no}

4. prefix string

5. exit

6. dial-peer voice tag voip

7. destination-pattern [+]string [T]

8. session target {ipv4:destination-address | dns:[$s$. | $d$. | $e$. | $u$. hostname | loopback:rtp | loopback:compressed | loopback:uncompressed | ras}

9. exit

10. voice-port slot/subunit/port

11. connection {tie-line | trunk [answer-mode]} string

12. exit

DETAILED STEPS

 
Command
Purpose

Step 1 

Router(config)# dial-peer voice tag pots

Enters dial-peer configuration mode for a particular POTS peer.

Step 2 

Router(config-dial-peer)# destination-pattern [+]string [T]

Defines the telephone number associated with the POTS dial peer. Keywords and argument are as follows:

Plus sign (+)—(Optional) Character indicating an E.164 standard number. The plus sign (+) is not supported on the Cisco MC3810.

string—Series of digits that specify the E.164 or private dialing plan telephone number. Valid entries are the digits 0 through 9, the letters A through D, and the following special characters:

Asterisk (*) and pound sign (#) that appear on standard touch-tone dial pad.

Comma (,) inserts a pause between digits.

Period (.) matches any entered digit (this character is used as a wildcard).

T—Indicates that the control character that the destination-pattern value is a variable length dial-string.

Step 3 

Router(config-dial-peer)# port {slot/subunit/port} | {slot/port:ds0-group-no}

Associates the POTS dial peer with a specific logical dial interface. Arguments are as follows:

slotLocation of the voice interface card. Range: 0 to 3, depending on the slot where the card is installed.

subunitSubunit on the voice interface card where the voice port is located. Valid entries:  0 and 1.

portVoice-port number. Valid entries: 0 and 1.

slotRouter location of the installed voice port adapter. Range: 0 to 3.

portVoice interface card location. Range: 0 to 3.

ds0-group-no—Defined DS0 group number. Each group number is represented on a separate voice port. This enables definition of individual DS0s on the digital T1/E1 card.

Step 4 

Router(config-dial-peer)# prefix string

(Optional) Specifies the prefix for this POTS dial peer. The string argument is sent to the telephony interface first, before the telephone number (destination pattern) associated with the dial peer is sent.

Step 5 

Router(config-dial-peer)# exit

Exits the current mode.

Step 6 

Router(config)# dial-peer voice tag voip

Configures a VoIP peer. The tag argument uniquely identifies the VoIP dial peer.

Step 7 

Router(config-dial-peer)# destination-pattern [+]string [T]

Defines the destination telephone number associated with this VoIP dial peer.

Step 8 

Router(config-dial-peer)# session target {ipv4:destination-address | dns:[$s$. | $d$. | $e$. | $u$. hostname | loopback:rtp | loopback:compressed | loopback:uncompressed | ras}

Identifies the IP address of the appropriate port on the destination end router. Keywords and arguments are as follows:

ipv4:destination-address—IP address of the dial peer.

dns:hostname—Characters representing the name of the host device.

$s$.—Source destination pattern is part of the domain name.

$d$.—Destination number is part of the domain name.

$e$.—Called number digits are reversed, periods are added between each digit of the called number. The string is part of the domain name.

$u$.—Unmatched portion of the destination pattern (such as a defined extension number) is part of the domain name.

loopback:rtp—All voice data is looped back to the originating source. Applicable for VoIP peers.

loopback:compressed—All voice data is looped back in compressed mode to the originating source. Applicable for POTS peers.

loopback:uncompressed—All voice data is looped back in an uncompressed mode to the originating source. Applicable for POTS peers.

ras—RAS signaling function protocol is used. A gatekeeper translates the E.164 address into an IP address.

Step 9 

Router(config-dial-peer)# exit

Exits the current mode.

Step 10 

Router(config)# voice-port slot/subunit/port

Enters voice-port configuration mode for a specified voice port.

Step 11 

Router(config-voiceport)# connection {tie-line | trunk [answer-mode]} string

Specifies a tie-line connection to a PBX. Keywords and arguments are as follows:

tie-line—Used only on a Cisco MC3810 when additional prefixed digits are required. The combined set of digits routes the call into the network using the dial peers. Tie-line digits are automatically stripped by a terminating port.

trunk—Straight tie-line connection to a PBX.

answer-mode—(Optional) The router should not attempt to initiate a trunk connection, but rather wait for an incoming call before establishing the trunk. If one of the devices is for receiving calls only, use this option.

string—Destination telephone number configured for the destination VoIP dial peer. The value configured for the connection trunk command must match the value configured for the VoIP dial peer exactly.

Step 12 

Router(config-voiceport)# exit

Exits the current mode.

Configuring PLAR-OPX Connections

OPXs are off-premise extension connections that are used with the Cisco MC3810 only.

To configure PLAR-OPX connections, use the following commands.

SUMMARY STEP

1. voice-port slot/subunit/port

2. connection plar-opx string

3. exit

DETAILED STEP

 
Command
Purpose

Step 1 

Router(config)# voice-port slot/subunit/port

Enters voice-port configuration mode for a specified voice port.

Step 2 

Router(config-voiceport)# connection plar-opx string

Specifies a PLAR-OPX connection on the Cisco MC3810, associating a peer directly with an interface. The local voice port provides a local response before the remote voice port receives an answer. On FXO interfaces, the voice port does not answer until the remote side answers.

Step 3 

Router(config-voiceport)# exit

Exits the current mode.

Configuration Examples for Trunk Conditioning and Connections

This section provides the following configuration examples:

Trunk-Conditioning: Example

PLAR (Switched Calls) Configuration: Example

Permanent Trunks Configuration: Example

Trunk-Conditioning: Example

The following example configures a voice class and then applies it to a VoFR and VoATM dial peer on a Cisco  MC3810 series.

Router(config)# voice class permanent 10
Router(config-class)# signal keepalive 10
Router(config-class)# signal pattern idle receive 0101
Router(config-class)# signal pattern idle transmit 0101
Router(config-class)# signal timing idle suppress-voice 5
Router(config-class)# signal pattern oos receive 0001
Router(config-class)# signal pattern oos transmit 0001
Router(config-class)# signal timing oos timeout 60
Router(config-class)# signal timing oos restart 120
Router(config-class)# signal timing oos suppress-voice 30
Router(config)# dial peer voice vofr 10
Router(config-dial-peer)# voice-class permanent 10
Router(config)# dial peer voice voatm 20
Router(config-dial-peer)# voice-class permanent 10

The following example configures a voice class using default idle and OOS signaling patterns and configures busyout to the PBX after a 60-second loss of signaling packets, with restart after 120 seconds.

Router(config)# voice class permanent 10
Router(config-class)# signal keepalive 10
Router(config-class)# signal timing oos timeout 60
Router(config-class)# signal timing idle suppress-voice 5
Router(config-class)# signal timing oos restart 120
Router(config-class)# exit
Router(config)# dial peer voice vofr 10
Router(config-dial-peer)# voice-class permanent 10
Router(config-dial-peer)# exit
Router(config)# dial peer voice voatm 20
Router(config-dial-peer)# voice-class permanent 10
Router(config-dial-peer)# exit

The following configuration example shows a voice class with specified signaling bit patterns for the idle receive and transmit; OOS receive and transmit states; and busyout to the PBX after a 90-second loss of signaling packets with restart after 240 seconds:

Router(config)# voice class permanent 30
Router(config-class)# signal keepalive 10
Router(config-class)# signal pattern idle receive 0101
Router(config-class)# signal pattern idle transmit 0101
Router(config-class)# signal pattern oos receive 0001
Router(config-class)# signal pattern oos transmit 0001
Router(config-class)# signal timing oos timeout 90
Router(config-class)# signal timing idle suppress-voice 5
Router(config-class)# signal timing oos restart 240
Router(config-class)# exit
Router(config)# voice-port 0/1:5
Router(config-voiceport)# voice-class permanent 30

The following configuration example shows a voice class using default idle and OOS signaling patterns and configures busyout after 60 seconds to the PBX, with restart after 120 seconds. It applies the voice class to both VoFR and VoATM dial peers:

Router(config)# voice class permanent 10
Router(config-class)# signal keepalive 10
Router(config-class)# signal timing oos timeout 60
Router(config-class)# signal timing idle suppress-voice 5
Router(config-class)# signal timing oos restart 120
Router(config-class)# exit
Router(config)# dial peer voice vofr 10
Router(config-dial-peer)# voice-class permanent 10
Router(config-dial-peer)# exit
Router(config)# dial peer voice voatm 20
Router(config-dial-peer)# voice-class permanent 10
Router(config-dial-peer)# exit

The following example configures a voice class with specified signaling bit patterns for the idle receive, idle transmit, OOS receive, and OOS transmit states, and configures busyout after 90 seconds to the PBX, with restart after 240 seconds. It applies the voice class to digital voice port 0:5 on a Cisco MC3810.

Router(config)# voice class permanent 30
Router(config-class)# signal keepalive 10
Router(config-class)# signal pattern idle receive 0101
Router(config-class)# signal pattern idle transmit 0101
Router(config-class)# signal pattern oos receive 0001
Router(config-class)# signal pattern oos transmit 0001
Router(config-class)# signal timing oos timeout 90
Router(config-class)# signal timing idle suppress-voice 5
Router(config-class)# signal timing oos restart 240 
Router(config-class)# exit
Router(config)# voice-port 0:5
Router(config-voiceport)# voice-class permanent 30

PLAR (Switched Calls) Configuration: Example

The following example configures the DTMF relay and PLAR for router alpha.

hostname router-alpha
!
voice-card 1
!
controller T1 1/0
 framing esf
 linecode b8zs
 ds0-group 1 timeslot 1 type fxo-loop
 ds0-group 2 timeslot 2 type fxo-loop
!
dial-peer voice 1 voip
 dtmf-relay  h245-alpha
 codec g729a
 destination-pattern 2..
 session target ipv4:192.168.100.2
!
dial-peer voice 2 pots
 destination-pattern 101
 port 1/0:1
!
dial-peer voice 3 pots
 destination-pattern 102
 port 1/0:2
!
voice-port 1/0:1
 connection plar 201
!
voice-port 1/0:2
 connection plar 202
!
interface s0/0
 ip address 192.168.100.1 255.255.255.0

The following example configures the DTMF relay for router beta.

hostname router-beta
!
dial-peer voice 1 voip
 destination-pattern 1..
 dtmf-relay h245-alpha
 codec g729a
 session target ipv4:192.168.100.1
!
dial-peer voice 2 pots
 destination-pattern 201
 port 1/1
!
dial-peer voice 3 pots
 destination-pattern 202
 port 1/2
!
voice-port 1/1
!
voice-port 1 / 2
!
interface serial 0/0
 ip address 192.168.100.2 255.255.255.0

Permanent Trunks Configuration: Example

A trunk connection can be used only between E&M ports or with FXO-to-FXS connections. The following example configures the alpha router:

hostname router-alpha
!
voice-card 1
!
controller T1 1/0
 framing esf
 linecode b8zs
 ds0-group 1 timeslot 1 type e&m-wink
 ds0-group 2 timeslot 2 type e&m-wink
 clock source line
!
voice-port 1/0:1
 connection trunk 1111
!
voice-port 1/0:2
 connection trunk 1112
!
dial-peer voice 1 voip
 dtmf-relay h245-alpha
 codec g729a
 destination-pattern 111.
 session target ipv4:192.168.100.2
!
dial-peer voice 2 pots
 destination-pattern 2221
port 1/0:1
!
dial-peer voice 3 pots
 destination-pattern 2222
 port 1/0:2
!
interface serial 0/0
 ip address 192.168.100.1 255.255.255.0

The following example configures the beta router:

hostname router-beta
!
voice-card 1
!
controller T1 1/0
 framing esf
 linecode b8zs
 ds0-group 1 timeslot 1 type e&m-wink
 ds0-group 2 timeslot 2 type e&m-wink
 clock source line
!
voice-port 1/0:1
 connection trunk 2221
!
voice-port 1/0:2
 connection trunk 2222
!
dial-peer voice 1 voip
 dtmf-relay h245-alpha
 codec g729a
 destination-pattern 222.
 session target ipv4:192.168.100.1
!
dial-peer voice 2 pots
 destination-pattern 1111
 port 1/0:1
!
dial-peer voice 3 pots
 destination-pattern 1112
 port 1/0:2
!
interface serial 0/0
 ip address 192.168.100.2 255.255.255.0

In this configuration, a permanent and transparent path is set up between individual DS0s on each router. It passes dial tone from the remote PBX and passes DTMF digits out of band.

The connection command, using the keyword trunk, establishes the permanent trunk connection between the routers. The digits after the command are passed internally within the router to match a dial peer so that the call can be set up.

How to Configure Trunk Monitoring and Management

This section contains the following procedures:

Configuring Analog Centralized Automatic Message Accounting E911 Trunk

Configuring Analog DID

Configuring Call Admission Control

Configuring Local and Advanced Voice Busyout

Configuring PSTN Fallback

Configuring Analog Centralized Automatic Message Accounting E911 Trunk

This section contains the following procedures (each task identified as either optional or required):

Configuring CAMA Card for CAMA Signaling (optional)

Configuring ANI Mapping (optional)

Verifying CAMA Signaling (optional)

Troubleshooting Tips (optional)

Monitoring and Maintaining Analog CAMA-E911 (optional)

Restrictions

You must install a CAMA card.

The following are not supported:

MCGP

Direct trunking

Automatic location information (ALI)/Data Management Systems (DMS) Reverse ALI lookup features of E911

Alternate routing for busy traffic and night service for power failure

Prerequisites


Note For information on the following configuration tasks, see the "Related Documents" section.


Install a CAMA card.

Configure IP routing.

Configure voice ports.

Configure VoIP.

Set up call agents (for information, see the documentation that accompanies the call agent).

Configuring CAMA Card for CAMA Signaling

To configure a CAMA card for CAMA signaling, use the following commands.


Note When the FXO-M1 port is not configured for CAMA signaling, the port functions as a normal foreign exchange office (FXO) port and all of the existing functionality is available.


SUMMARY STEPS

1. voice-port slot/subunit/port

2. signal {cama {KP-0-NXX-XXXX-ST | KP-0-NPA-NXX-XXXX-ST | KP-2-ST | KP-NPD-NXX-XXXX-ST} | groundstart | loopstart}}

3. shutdown

4. no shutdown

5. exit

DETAILED STEPS

 
Command
Purpose

Step 1 

Router(config)# voice-port slot/subunit/port

Enters voice-port configuration mode for a specified voice port.

Step 2 

Router(config-voiceport)# signal {cama {KP-0-NXX-XXXX-ST | KP-0-NPA-NXX-XXXX-ST | KP-2-ST | KP-NPD-NXX-XXXX-ST} | groundstart | loopstart}}

Selects the desired signal and specifies the type of CAMA signaling. The following are the four CAMA signaling options:

Type 1—KP-0-NXX-XXXX-ST

Type 2—KP-0-NPA-NXX-XXXX-ST

Type 3—KP-2-ST

Type 4—KP-NPD-NXX-XXXX-ST

Step 3 

Router(config-voiceport)# shutdown

Disables all voice ports on the voice interface card.

Step 4 

Router(config-voiceport)# no shutdown

Enables CAMA signaling.

Step 5 

Router(config-voiceport)# exit

Exits the current mode.


Note Both ports on the CAMA card configure simultaneously.


Configuring ANI Mapping

To configure a CAMA card for 8-digit ANI transmission, use the following commands.

SUMMARY STEPS

1. voice-port slot/subunit/port

2. timing digit ms

3. timing interdigit ms

4. ani mapping NPD-value NPA-number

5. exit

DETAILED STEPS

 
Command
Purpose

Step 1 

Router(config)# voice-port slot/subunit/port

Enters voice-port configuration mode for a specified voice port.

Step 2 

Router(config-voiceport)# timing digit ms

(Optional) Specifies the DTMF-digit signal duration for a specified voice port, in ms. Default: 75.

Step 3 

Router(config-voiceport)# timing interdigit ms

(Optional) Specifies the DTMF interdigit duration for a specified voice port, in ms. Default: 65.

Step 4 

Router(config-voiceport)# ani mapping NPD-value NPA-number

Builds the table that translates the Numbering Plan Area (NPA), or area code, into a single MF digit. The number of numbering plan digits (NPD) programmed is determined by local policy and the number of NPAs or area codes that the PSAP serves. NPD range: 0 to 3. NPA range: 100to 999.

Note Repeat until all NPAs (area codes) are configured or until the NPD range maximum is reached.

Step 5 

Router(config-voiceport)# exit

Exits the current mode.

Verifying CAMA Signaling

To verify that the CAMA card is configured for CAMA signaling and ANI mapping, use the show run command.

To verify that the voice ports are configured for CAMA signaling, use the show voice-port command.

Troubleshooting Tips

To troubleshoot the analog CAMA E911 feature, perform the following steps:

To enable debugging on all virtual voice port module (VPM) areas, use the debug vpm all command.

To turn off all port-level debugging, use the no debug vpm all command. We recommend that you turn of all debugging and then enter the individual debug commands desired to avoid confusion about which ports you are actually debugging.

To troubleshoot specific areas of the analog CAMA E911 feature, use the following commands in EXEC mode:

 
Command
Purpose
 
Router# debug vpm dsp

Displays messages from the DSP on the VPM to the router.

 
Router# debug vpm error

Displays processing errors in the voice telephony service provider.

 
Router# debug vpm port

Limits the debug vpm all command to a specified port.

 
Router# debug vpm spi

Traces how the voice port module SPI interfaces with the call control API.

 
Router# debug vpm trunk_sc

Enables the display of trunk conditioning supervisory component trace information.

 
Router# show debug

Displays which debug commands are enabled.

 
Router# debug vtsp all

Displays debugging information for all of the debug vtsp commands.

Monitoring and Maintaining Analog CAMA-E911

To display configuration information about a specific voice port, use the following commands in EXEC mode:

 
Command
Purpose
 

Router# show voice port [slot/subunit/port | summary]

Verifies that the VIC-2CAMA card recognizes CAMA signaling and verifies that the changes to the port configuration have been made.

 

Router# show run

Verifies that the VIC-2CAMA card is configured for CAMA signaling and ANI mapping.

Configuring Analog DID

This section contains the following procedures (each identified as either optional or required):

Configuring Voice Ports to Support DID (required)

Verifying DID Voice-Port Configuration (optional)

Restrictions

Dial tone is not present on DID voice ports.

Outgoing calls are not allowed on DID voice ports. If an outgoing call is attempted, the caller gets a fast busy signal.

Prerequisites


Note For information on the following configuration tasks, see the "Related Documents" section.


Obtain DID service from your service provider.

Establish a working network.

Complete your company's dial plan.

Establish a working telephony network based on your company's dial plan.

Install the DID cards (for information, see your platform installation guide).

Install at least one other network module or WAN interface card to provide the connection to the LAN or WAN.

Configuring Voice Ports to Support DID

To configure voice ports for DID, use the following commands. Not all commands required to configure voice ports appear here. Use the reference information in the "Analog DID Feature" section to find out more about voice-port configuration.

SUMMARY STEPS

1. voice-port slot/subunit/port

2. signal did {immediate | wink-start | delay-dial}

3. timing wait-wink ms

4. timing wink-wait ms

5. timing wink-duration ms

6. timing delay-duration ms

7. timing delay-start ms

8. exit

DETAILED STEPS

 
Command
Purpose

Step 1 

Router(config)# voice-port slot/subunit/port

Enters voice-port configuration mode for a specified voice port.

Step 2 

Router (config-voiceport)# signal did 
{immediate | wink-start | delay-dial}

Enables DID on the voice port. Keywords are as follows:

immediate—Voice port uses the immediate-start protocol.

wink-start—Voice port uses the wink-start protocol.

delay-dial—Voice port uses the delay-start protocol.

Step 3 

Router(config-voiceport)# timing wait-wink ms

(Optional for wink-start ports only) Sets the maximum time to wait for wink signaling after an outgoing seizure is sent.

Step 4 

Router(config-voiceport)# timing wink-wait ms

(Optional for wink-start ports only) Sets the maximum time to wait before sending a wink-start signal after an incoming seizure is detected.

Step 5 

Router(config-voiceport)# timing wink-duration 
ms

(Optional for wink-start ports only) Sets the duration of a wink-start signal.

Step 6 

Router(config-voiceport)# timing delay-duration 
ms

(Optional for delay-dial ports only) Sets the duration of the delay signal.

Step 7 

Router(config-voiceport)# timing delay-start ms

(Optional for delay-dial ports only) Sets the delay interval after an incoming seizure is detected.

Step 8 

Router(config-voiceport)# exit

Exits the current mode.

Verifying DID Voice-Port Configuration

To verify voice-port configuration, use the show voice port command. You can specify a voice port or display the status of all configured voice ports. In the following example, the specified Cisco 2600 FXS port is configured for DID:

Router# show voice port 1/0/0

Foreign Exchange Station with Direct Inward Dialing (FXS-DID) 1/0/0 Slot is 1, Sub-unit is 
0, Port is 0
 Type of VoicePort is DID-IN
 Operation State is DORMANT
 Administrative State is UP
 No Interface Down Failure
 Description is not set
 Noise Regeneration is enabled
 Non Linear Processing is enabled
 Music On Hold Threshold is Set to -38 dBm
 In Gain is Set to 0 dB
 Out Attenuation is Set to 0 dB
 Echo Cancellation is enabled
 Echo Cancel Coverage is set to 8 ms
 Playout-delay Mode is set to default
 Playout-delay Nominal is set to 60 ms
 Playout-delay Maximum is set to 200 ms
 Connection Mode is normal
 Connection Number is not set
 Initial Time Out is set to 10 s
 Interdigit Time Out is set to 10 s
 Ringing Time Out is set to 180 s
 Companding Type is u-law
 Region Tone is set for US
 Analog Info Follows:
 Currently processing none
 Maintenance Mode Set to None (not in mtc mode)
 Number of signaling protocol errors are 0
 Impedance is set to 600r Ohm
 Wait Release Time Out is 30 s
 Station name None, Station number None
 Voice card specific Info Follows:
 Signal Type is wink-start
 Dial Type is dtmf
 In Seizure is inactive
 Out Seizure is inactive
 Digit Duration Timing is set to 100 ms
 InterDigit Duration Timing is set to 100 ms
 Pulse Rate Timing is set to 10 pulses/second
 InterDigit Pulse Duration Timing is set to 750 ms
 Clear Wait Duration Timing is set to 400 ms
 Wink Wait Duration Timing is set to 200 ms
 Wait Wink Duration Timing is set to 550 ms
 Wink Duration Timing is set to 200 ms
 Delay Start Timing is set to 300 ms
 Delay Duration Timing is set to 2000 ms
 Dial Pulse Min. Delay is set to 140 ms
 Percent Break of Pulse is 60 percent
 Auto Cut-through is disabled
 Dialout Delay for immediate start is 300 ms

Configuring Call Admission Control

This section contains the following procedures:

Configuring Call Admission Control for H.323 VoIP Gateways

Configuring MGCP VoIP Call Admission Control

Configuring Call Admission Control for H.323 VoIP Gateways

This section contains the following procedures (each identified as either required or optional):

Configuring Call Spike (required)

Configuring Call Threshold (required)

Configuring Call-Threshold Poll Interval (optional)

Configuring Call Treatment (optional)

Verifying Call Admission Control (optional)

Restrictions

The following are applicable to the CAC Control for H.323 VoIP Gateways feature in conjunction with the PSTN Fallback feature only:

Upon detecting network congestion, the PSTN Fallback feature does nothing to the existing call. The PSTN Fallback feature affects only subsequent calls.

There is a single ICPIF/delay-loss value per system.

The PSTN Fallback feature adds a small call setup delay for the first call to a new IP destination.

H.323 VoIP calls are supported.

Prerequisites


Note For information on the following configuration tasks, see the "Related Documents" section.


Configure VoIP.

Ensure that you have the correct Cisco IOS release for your platform (use Cisco Feature Navigator on Cisco.com).

Configuring Call Spike

To configure a call spike, use the following command.

SUMMARY STEP

call spike call-number [steps number-of-steps size ms]

DETAILED STEP

 
Command
Purpose
 

Router(config)# call spike call-number [steps number-of-steps size ms]

Configures the limit for the number of incoming calls in a short period of time.

Configuring Call Threshold

To configure a call threshold, use the following command.

SUMMARY STEP

call threshold {global trigger-name | interface interface-name interface-number int-calls} low value high value [busyout | treatment]

DETAILED STEP

 
Command
Purpose
 

Router(config)# call threshold {global trigger-name | interface interface-name interface-number int-calls} low value high value [busyout | treatment]

Enables a resource and defines associated parameters. Action is enabled when the resource cost goes beyond the high value and is not disabled until the resource cost drops below the low value.

Configuring Call-Threshold Poll Interval

To configure a call-threshold poll interval, use the following command.

SUMMARY STEP

call threshold poll-interval {cpu-average | memory} seconds

DETAILED STEP

 
Command
Purpose
 

Router(config)# call threshold poll-interval {cpu-average | memory} seconds

Enables a polling interval threshold for CPU or memory.

Configuring Call Treatment

To configure call treatment, use the following command.

SUMMARY STEP

call treatment {on | action action [value] | cause-code cause-code | isdn-reject value}

DETAILED STEP

 
Command
Purpose
 

Router(config)# call treatment {on | action action [value] | cause-code cause-code | isdn-reject value}

Configures how calls should be processed when local resources are unavailable and indicates whether the call should be disconnected (with cause code), hairpinned, or a message or busy tone played to the user.

Verifying Call Admission Control


Step 1 show call spike status

Use this command to display the configured call spike threshold and statistics for incoming calls.

Step 2 show call threshold

Use this command to display enabled triggers, current values for configured triggers, and number of application programming interface (API) calls that were made to global and interface resources.

Step 3 show call treatment

Use this command to display the call treatment configuration and the statistics for handling the calls based upon resource availability.

Step 4 show running-configuration

Use this command to display the full running configuration.


Configuring MGCP VoIP Call Admission Control

This section contains the following procedures (each identified as either required or optional; you can perform any combination of optional procedures):

Configuring MGCP for Call Admission Control (required)

Configuring MGCP SRC CAC (optional)

Configuring MGCP RSVP CAC (optional)

Configuring MGCP-SA-Agent CAC (optional)

Verifying the MGCP VoIP CAC Configuration (optional)

Troubleshooting the MGCP VoIP CAC Configuration (optional)

Restrictions

MGCP VoIP CAC is not supported on the NCS 1.0 and TGCP 1.0 profiles of MGCP 1.0.

Fax/modem pass-through and fax/modem relay are not supported in MGCP VoIP CAC.

The call agent has responsibility for treating calls that have been refused by the gateway because of insufficient resources.

MGCP VoIP CAC does not attempt to identify the network element that is causing the resource problem. Calls may be successful if they are routed around the congested or unavailable network element.

MGCP VoIP CAC does not support the classification of calls into different priority levels, also referred to as policy control.

MGCP VoIP CAC does not address maintenance capabilities, such as bringing an out-of-service trunk back into service or handling lost communication with a call agent, even though such capabilities impact call processing resources.

On routers that accept both voice and data calls, SRC CAC does not count data calls in its calculation of total calls.

SA Agent CAC is not supported on the MGCP 0.1 protocol.


Note SRC CAC and SA Agent CAC are configured on the gateway. The call agent controls RSVP CAC, but the gateway needs to be configured with appropriate bandwidth to support RSVP CAC messages.


Prerequisites


Note For information on the following configuration tasks, see the "Related Documents" section.


Configure IP routing.

Configure voice ports.

Configure VoIP.

Set up call agents (for information, see the documentation that accompanies the call agent).

Configure other MGCP, SRC, RSVP, and SA Agent parameters as needed.

Configuring MGCP for Call Admission Control

Only the mgcp command and the mgcp call-agent command are required to configure MGCP on a gateway. Other commands may be used to fine-tune the MGCP application. They are described in the documents listed in the "MGCP VoIP Call Admission Control Feature" section.

To configure MGCP for CAC, use the following commands.

SUMMARY STEPS

1. mgcp [gw-port]

2. mgcp call-agent {dns-name | ip-address} [ca-port] [service-type type] [version protocol-version]

3. mgcp package-capability package

4. mgcp default-package package

DETAILED STEPS

 
Command
Purpose

Step 1 

Router(config)# mgcp [gw-port]

Starts and allocates resources for the MGCP daemon. The argument is as follows:

gw-port—UDP port for the MGCP gateway. Range: 1025 to 65535.

Step 2 

Router(config)# mgcp call-agent {dns-name | ip-address} [ca-port] [service-type type] [version protocol-version]

Configures the MGCP call agent and service type. Keywords and arguments are as follows:

dns-name—Fully qualified domain name (including host portion) for the call agent. For example, ca123.example.net.

ip-address—IP address for the call agent.

ca-port—UDP port number over which the gateway sends messages to the call agent. Range: 1025 to 65535. Default for MGCP 1.0: 2727. Default for MGCP 0.1: 2427.

service-type type—Protocol service type. Valid value for MGCP CAC: mgcp. Default: 0.1.

version protocol-version—Valid values MGCP and CAC: 0.1 and 1.0. Default: 0.1.

Step 3 

Router(config)# mgcp package-capability package

(Optional) Enables availability of the specified MGCP package on the gateway. Repeat this command for each additional package that you want to make available to the gateway.

The range of packages that you can select from depends on your platform and the type of gateway that you are configuring. Use command-line help to determine available packages by entering the mgcp package-capability ? command in global configuration mode.

Step 4 

Router(config)# mgcp default-package package

 

Configuring MGCP SRC CAC

To determine if the local gateway has sufficient resources to handle voice calls, MGCP SRC CAC checks those resources against the thresholds that you specify in this configuration task. The commands listed here are the minimum required to configure MGCP SRC CAC. Other commands to fine-tune SRC CAC are described in the SRC CAC document listed in the "MGCP VoIP Call Admission Control Feature" section.


Note Network access server data calls are not counted by SRC in the total calls calculations.


To configure MGCP SRC CAC, use the following commands.

SUMMARY STEPS

1. call threshold global trigger-name low value high value treatment

2. call threshold poll-interval [cpu-avg number | memory number]

3. mgcp src-cac

DETAILED STEPS

 
Command
Purpose

Step 1 

Router(config)# call threshold global trigger-name low value high value treatment

Enables a resource and defines its parameters. Treatment of attempted calls is enabled when the resource cost goes beyond the high value. Treatment is not disabled until the resource cost drops below the low value. Arguments and keywords are as follows:

trigger-name—One of the following:

cpu-5sec—CPU utilization for previous 5 seconds.

cpu-avg—Average CPU utilization.

io-mem—I/O memory utilization.

proc-mem—Processor memory utilization.

total-calls—Total number of calls.

total-mem—Total memory utilization.



low value—Low threshold. Range: 1 to 100 (%) for utilization triggers and 1 to 10000 (calls) for total-calls.

high value—High threshold. Range: 1 to 100 (%) for utilization triggers and 1 to 10000 (calls) for total-calls.

treatment—A call treatment is to be applied by the call agent when the resource is not available.

If network conditions rise above the high threshold value, SRC rejects the call by sending the call agent an MGCP error message with the return code 403. The call agent applies a treatment to the rejected call.

Note Error code 403 was originally numbered 502.

Step 2 

Router(config)# call threshold poll-interval [cpu-avg number | memory number]

(Optional) Establishes a testing period length for the CPU or memory.Keywords and arguments are as follows:

cpu-avg number—(Optional) CPU average interval, in seconds. Range: 1 to 60. Default: 60.

memory number—(Optional) Memory average interval, in seconds. Range: 1 to 60. Default: 5.

Step 3 

Router(config)# mgcp src-cac

Enables SRC CAC on the MGCP gateway.

Configuring MGCP RSVP CAC

MGCP RSVP CAC configuration requires the synchronization of the call setup signaling and the RSVP signaling. This synchronization guarantees that the called-party phone rings only after the resources for the call have been reserved. This synchronization also gives voice gateways the control of what action to take before the call setup moves to the alerting stage if the reservation fails or cannot be completed within a predefined period of time.

A timer can be set by using the call rsvp-sync resv-timer command to limit the number of seconds for which the terminating gateway waits for bandwidth reservation setup before proceeding with the call setup or releasing the call, depending on the QoS level configured in the dial peers. The timer defaults to 10 seconds.

Enable RSVP on the appropriate interfaces on your gateway by using the ip rsvp bandwidth interface configuration command. You must also enable fair queueing on these interfaces by using the fair-queue interface configuration command.

The commands listed here are the minimum required to configure MGCP RSVP CAC.


NoteFor information on enabling RSVP and fair queueing, see the description of the fair-queue (WFQ) command in the Cisco IOS Quality of Service Solutions Command Reference, Release 12.3.

For information on other commands to fine-tune RSVP CAC, see the "Related Documents" section.


To configure MGCP RSVP CAC, use the following commands.

SUMMARY STEPS

1. call rsvp-sync

2. call rsvp-sync resv-timer seconds

3. interface type [number]

4. ip rsvp bandwidth [interface-kbps [single-flow-kbps]]

5. fair-queue [congestive-discard-threshold [dynamic-queues [reservable-queues]]]

6. exit

DETAILED STEPS

 
Command
Purpose

Step 1 

Router(config)# call rsvp-sync

Enables synchronization between RSVP and the call setup signaling protocol.

Step 2 

Router(config)# call rsvp-sync resv-timer seconds

(Optional) Adjusts the timer for reservation requests, in seconds. Default: 10.

Step 3 

Router(config)# interface type [number]

Enters interface configuration mode.

Step 4 

Router(config-if)# ip rsvp bandwidth [interface-kbps [single-flow-kbps]]

Enables RSVP for IP on an interface. RSVP is disabled by default. Arguments are as follows:

interface-kbps—(Optional) Maximum amount of bandwidth, in kbps, that may be allocated by RSVP flows. Range: 1 to 10000000.

single-flow-kbps—(Optional) Maximum amount of bandwidth, in kbps, that may be allocated to a single flow. Range: 1 to 10000000.

Step 5 

Router(config-if)# fair-queue [congestive-discard-threshold [dynamic-queues [reservable-queues]]]

(Optional) Enables weighted fair queueing (WFQ) for an interface. Arguments are as follows:

congestive-discard-threshold—(Optional) Number of messages allowed in each queue. Range: a power of 2 in from 16 to 4096. Default: 64. When a conversation reaches this threshold, new message packets are discarded.

dynamic-queues—(Optional) Number of dynamic queues used for best-effort conversations (that is, a normal conversation that does not require any special network services). Valid values: 16, 32, 64, 128, 256, 512, 1024, 2048, and 4096.

reservable-queues—(Optional) Number of reservable queues used for reserved conversations. Range: 0 to 1000. Default: 0. Reservable queues are used for interfaces that are configured for features such as RSVP.

Step 6 

Router(config-if)# exit

Exits the current mode.

Configuring MGCP-SA-Agent CAC

The Cisco SA Agent is an application-aware synthetic operation agent that monitors network performance by measuring response time, network resource availability, application performance, jitter (interpacket delay variance), connect time, throughput, and packet loss. Performance can be measured between any Cisco device that supports this feature and any remote IP host (server), Cisco routing device, or mainframe host. Performance measurement statistics provided by this feature can be used for troubleshooting, for problem analysis, and for designing network topologies.

The SA Agent Responder that is enabled using the rtr responder command is a component embedded in the target Cisco routing device that allows the system to anticipate and respond to SA Agent request packets. The responder can listen on any user-defined port for UDP and TCP protocol messages. In a client/server terminology, the SA Agent Responder is a concurrent multiservice server.


Note The Cisco SA Agent feature is an expansion of the Response Time Reporter (RTR) feature introduced in Cisco IOS Release 11.2. SA Agent retains the use of the RTR acronym in many of the configuration commands and for the configuration mode used to configure SA Agent operations. RTR is also used throughout the command-line interface (CLI) in the output of help and show commands.


To configure MGCP-SA-Agent CAC, use the following commands. The commands listed here are the minimum required to configure MGCP-SA-Agent CAC. Other fine-tuning commands are described in the SA-Agent CAC documents listed in the "MGCP VoIP Call Admission Control Feature" section.

SUMMARY STEPS

1. call fallback active

2. mgcp rtrcac

3. rtr responder

DETAILED STEPS

 
Command
Purpose

Step 1 

Router(config)# call fallback active

Enables a call request to fall back to alternate dial peers in case of network congestion.

Step 2 

Router(config)# mgcp rtrcac

Enables MGCP SA Agent CAC.

Step 3 

Router(config)# rtr responder

Enables the SA Agent responder functionality on a Cisco device.

Verifying the MGCP VoIP CAC Configuration


Step 1 show running-configuration

Use this command to display the current configuration settings.

Step 2 show mgcp

Use this command to display MGCP configuration information.

Bold lines in the following command output indicate that the MGCP VoIP SA Agent CAC and SRC CAC are disabled.

Router# show mgcp

MGCP Admin State ACTIVE, Oper State ACTIVE - Cause Code NONE
MGCP call-agent: 172.18.195.147 2300 Initial protocol service is SGCP 1.5
MGCP block-newcalls DISABLED
MGCP send RSIP for SGCP is ENABLED
MGCP quarantine mode discard/step
MGCP quarantine of persistent events is ENABLED
MGCP dtmf-relay for VoIP disabled for all codec types
MGCP dtmf-relay voaal2 codec all
MGCP voip modem passthrough mode: NSE, codec: g711ulaw, redundancy: DISABLED,
MGCP voaal2 modem passthrough mode: NSE, codec: g711ulaw
MGCP TSE payload: 100
MGCP T.38 Named Signalling Event (NSE) response timer: 200
MGCP Network (IP/AAL2) Continuity Test timer: 3000
MGCP 'RTP stream loss' timer: 2
MGCP request timeout 500
MGCP maximum exponential request timeout 4000
MGCP gateway port: 2427, MGCP maximum waiting delay 3000
MGCP restart delay 0, MGCP vad DISABLED
MGCP rtrcac DISABLED
MGCP system resource check DISABLED
MGCP xpc-codec: DISABLED, MGCP persistent hookflash: DISABLED
MGCP persistent offhook: ENABLED, MGCP persistent onhook: DISABLED
MGCP piggyback msg DISABLED, MGCP endpoint offset DISABLED
MGCP simple-sdp DISABLED
MGCP undotted-notation DISABLED
MGCP codec type g711ulaw, MGCP packetization period 20
MGCP JB threshold lwm 30, MGCP JB threshold hwm 150
MGCP LAT threshold lmw 150, MGCP LAT threshold hwm 300
MGCP PL threshold lwm 1000, MGCP PL threshold hwm 10000
MGCP CL threshold lwm 1000, MGCP CL threshold hwm 10000
MGCP playout mode is adaptive 60, 4, 200 in msec
MGCP IP ToS low delay disabled, MGCP IP ToS high throughput disabled
MGCP IP ToS high reliability disabled, MGCP IP ToS low cost disabled
MGCP IP RTP precedence 5, MGCP signaling precedence: 3
MGCP default package: line-package
MGCP supported packages: gm-package dtmf-package trunk-package line-package hs-package 
atm-package ms-package dt-package res-package mt-package

Step 3 show call threshold configuration

Use this command to display the SRC CAC configuration.

Router# show call threshold configuration

Some resource polling interval:
  CPU_AVG interval: 60
  Memory interval:  5

IF      Type         Value   Low   High  Enable
-----   ----         -----   ----  ----  ------
N/A     cpu-5sec     43      0     80    treatment
N/A     cpu-avg      27      60    80    treatment
N/A     io-mem       15      60    80    treatment
N/A     proc-mem     24      60    80    treatment
N/A     total-mem    22      60    80    treatment
N/A     total-calls  0       5     12    treatment


Troubleshooting the MGCP VoIP CAC Configuration

MGCP VoIP CAC has several commands available to analyze call statistics and operation of applications on the gateway. They are classified into these groups for clarity:

Troubleshooting MGCP

Troubleshooting MGCP SRC CAC

Troubleshooting MGCP RSVP CAC

Troubleshooting MGCP SA Agent CAC

Troubleshooting MGCP

To provide information about the operation of the MGCP application, use the following commands in privileged EXEC mode:

 
Command
Purpose
 

Router# debug mgcp all

Displays real-time MGCP errors, events, media, packets, parser, SRC, and VoIP CAC information.

 

Router# debug mgcp errors [endpoint endpoint-name]

Displays MGCP errors.

 

Router# debug mgcp events [endpoint endpoint-name]

Displays MGCP events.

 

Router# debug mgcp media [endpoint endpoint-name]

Displays MGCP tone and signal information.

 

Router# debug mgcp packets [endpoint endpoint-name | input-hex]

Displays MGCP packet information, with input packets optionally in hexadecimal format.

 

Router# debug mgcp parser

Displays MGCP parser and builder information.

 

Router# debug mgcp src

Displays MGCP SRC CAC information.

 

Router# debug mgcp voipcac

Turns on debugging messages for the VoIP CAC process at the MGCP application layer.

Troubleshooting MGCP SRC CAC

To help identify SRC CAC problems, use the following commands in privileged EXEC mode:

 
Command
Purpose
 

Router# show call threshold {status [unavailable] | stats}

Displays status of configured triggers or statistics for application programming interface (API) calls that were made to global and interface resources.

 

Router# show mgcp statistics

Displays MGCP statistics, including those for MGCP SRC VoIP CAC.

 

Router# clear call threshold stats

Clears call threshold statistics.

 

Router# clear mgcp src-stats

Clears statistics gathered for MGCP SRC CAC.

 

Router# debug call threshold

Displays details of trigger actions.

 

Router# debug mgcp src

Displays debug information for MGCP SRC CAC calls.

Troubleshooting MGCP RSVP CAC

To identify and trace RSVP CAC problems, use the following commands in privileged EXEC mode:

 
Command
Purpose
 

Router# show call fallback cache

Displays a network congestion level check result if one has been cached.

 

Router# show call rsvp-sync stats

Displays statistics for calls that attempted RSVP reservation.

 

Router# show call rsvp-sync conf

Displays the configuration settings for RSVP synchronization.

 

Router# show ip rsvp reservation

Displays the RSVP-related receiver information currently in the database.

 

Router# debug call rsvp-sync func-trace

Displays messages about software functions called by RSVP.

 

Router# debug call rsvp-sync events

Displays events that occur during RSVP setup.

 

Router# debug ip rsvp detail

Displays detailed information about RSVP-enabled and Subnetwork Bandwidth Manager (SBM) message processing.

Troubleshooting MGCP SA Agent CAC

To help identify SA Agent CAC problems, use the following commands in privileged EXEC mode:

 
Command
Purpose
 

Router# show call fallback cache

Displays a network congestion level check result if one has been cached.

 

Router# debug call fallback probes

Verifies that probes are being sent correctly.

 

Router# debug call fallback detail

Displays details of the VoIP call fallback.

 

Router# show rtr application [tabular | full]

Displays global information about the SA Agent feature. There are a number of other options for the show rtr command; use CLI help to browse a list of choices.

 

Router# debug rtr error

Enables logging of SA Agent run-time errors.

 

Router# debug rtr trace

Traces the execution of an SA Agent operation.

Configuring Local and Advanced Voice Busyout

A busyout trigger event can be configured at both the serial interface level and the voice-port level. If there is a conflict between the interface-level trigger event and the voice-port-level trigger event (trigger events for each are different), the voice-port-level trigger event overrides the interface-level trigger event.

If more than one interface is configured for a busyout trigger event, voice ports are not busied out until all of the interfaces are down.


Note ITU-T G.113, General Characteristics of International Telephone Connections and Telephone Circuits, is supported.


This section contains the following procedures:

Configuring the Busyout Trigger Event

Configuring a Voice Port to Busy Out

Configuring a Voice Port to Monitor the Link to a Remote Interface

Configuring a Busyout-Monitoring Voice Class

Configuring a Graceful Busyout

Configuring Busyout Monitor

Configuring Busyout Monitor Gatekeeper

Verifying Busyout Status

Restrictions

A maximum of 32 network interfaces can be monitored for a voice port.

The busyout feature is not activated when no DSP resources or bandwidth are available. These two conditions can be addressed by configuring alternate routing.

This feature is not supported on BRI cards.

Configuring the Busyout Trigger Event

To configure the voice-port busyout trigger event for a serial or ATM network interface, use the following commands.


Note If voice-port busyout from a serial network interface is configured and the serial interface goes down, all voice ports are placed in busyout state.


SUMMARY STEPS

1. interface type [number]

2. voice-port busyout

3. Ctrl-Z

4. show voice busyout

DETAILED STEPS

 
Command
Purpose

Step 1 

Router(config)# interface type [number]

Enters interface configuration mode.

Step 2 

Router(config-if)# voice-port busyout

Busies out all voice ports associated with this serial interface.

Note This command does not busy out any voice ports configured to busy out under specific conditions, as described in the "Forcing Busyout" section.

Step 3 

Router(config-if)# Ctrl-Z

Exits the current mode and enters EXEC mode.

Step 4 

Router# show voice busyout

Displays the voice busyout status.

Configuring a Voice Port to Busy Out

You can configure a voice port to busy out under specified conditions or you can manually force it to busy out using the following procedures:

Configuring Busyout Under Specified Conditions

Configuring Busyout-Seize Conditions

Forcing Busyout

The default is to busy out when the monitored interface is OOS.

Configuring Busyout Under Specified Conditions

To configure busyout under specified conditions, use the following commands.

SUMMARY STEP

1. voice-port slot/subunit/port

2. busyout monitor interface {serial interface-number | ethernet interface-number} [in-service]

3. exit

DETAILED STEP

 
Command
Purpose

Step 1 

Router(config)# voice-port slot/subunit/port

Enters voice-port configuration mode for a specified voice port.

Step 2 

Router(config-voiceport)# busyout monitor 
interface {serial interface-number | ethernet 
interface-number} [in-service]

Specifies an interface to be monitored. When multiple interfaces are configured for OOS, busy out occurs only if all of the interfaces are OOS. When multiple interfaces are configured for in-service, busy out occurs only when any one interface returns to service.

Keywords and arguments are as follows:

serial—Monitoring of a serial interface. More than one can be entered for a voice port.

interface-number—Interface to be monitored for the voice-port busyout function.

ethernet—Monitoring of an Ethernet interface.

interface-number—Interface to be monitored for the voice-port busyout function.

in-service—Configures the voice port for busy out when the monitored interface returns to service.

Note The voice-port command is hardware specific, as described in the Cisco IOS command references listed in the "Related Documents" section.

Reenter the command for each additional interface to be monitored.

Step 3 

Router(config-voiceport)# exit
Exits the current mode.

Configuring Busyout-Seize Conditions

To configure busyout-seize conditions, use the following commands.

SUMMARY STEPS

1. voice-port slot/subunit/port

2. busyout seize {ignore | repeat}

3. Ctrl-Z

4. show voice port

DETAILED STEPS

 
Command
Purpose

Step 1 

Router(config)# voice-port slot/subunit/port

Enters voice-port configuration mode for a specified voice port.

Step 2 

Router(config-voiceport)# busyout seize {ignore 
| repeat}

For FXO and FXS only. Configures the busyout-seize action for this voice port. Keywords are as follows:

ignore—Leaves the loop open and ignores the incoming signal.

repeat—Seizes the far end and ignores all incoming signals until the far end releases. Removes the seize signal and wait for one second before starting to seize the far end again.

Note For E&M voice ports, the busyout action is always to seize the far-end line.

Step 3 

Router(config-voiceport)# Ctrl-Z

Exits the current mode and enters EXEC mode.

Step 4 

Router# show voice port

Displays the configured busyout-seize actions for the voice ports.


Note The Cisco MC3810 returns the voice ports to an idle state when the event that triggered the busyout disappears.


The busyout seize action depends on the voice-port signaling type. Table 50 lists the busyout actions that take place. For E&M voice ports, the busyout action is always seize.

Table 50 Procedure Settings and Busyout Actions 

Voice-Port Signaling Types
Procedure Settings (Busyout-Option Command)
Busyout Actions

FXS loop-start

Default

Removes the power from the loop. For analog voice ports, this is equivalent to removing the ground from the tip lead. For digital voice ports, the port generates the bit pattern equivalent to removing the ground from the tip lead or busies out if the bit pattern exists.

Ignore

Ignores the ground on the ring lead.

FXS ground-start

Default

Grounds the tip lead and stays at this state.

Ignore

Leaves the tip lead open and ignores the ground on the ring lead.

Repeat

Grounds the tip lead and waits for the far end to close the loop. The far end closes the loop. If the far end opens the loop again, the FXS removes the ground from the tip lead. FXS waits for several seconds before starting the process again.

FXO loop-start

Default

Closes the loop and stays at this state.

Ignore

Leaves the loop open and ignores the ringing current on the ring level.

Repeat

Closes the loop. After the detected far end starts the power denial procedure, FXO opens the loop. After the detected far end has completed the power denial procedure, FXO waits for several seconds before starting the process again.

FXO ground-start

Default

Grounds the tip lead.

Ignore

Leaves the loop open and ignores the running current on the ring lead or ground on the tip lead.

Repeat

Grounds the ring lead and removes the ground from the ring lead. Closes the loop after the detected far end grounds the tip lead. When the detected far end removes the ground from the tip lead, FXO opens the loop. The FXO waits for several seconds before starting the process again.

E&M immediate-start

Default (only option available)

Seizes the far end by setting lead busy.

E&M delay-start

Default (only option available)

Seizes the far end by setting lead busy.

E&M wink-start

Default (only option available)

Seizes the far end by setting lead busy.


Forcing Busyout

When you configure busyout, the specified voice port is forced into a busyout state when the interface is down. If you enter the busyout forced command, the voice port is forced unconditionally into a busyout state. If you enter the voice-port busyout command on more than one interface, all interfaces must be down for the busyout to take effect. To configure a forced busyout condition, use the following commands.


Note If you force a voice port into the busyout state, you must manually force it out of the busyout state by using the no busyout forced command.


SUMMARY STEPS

1. voice-port slot/subunit/port

2. busyout forced

3. busyout monitor action graceful

4. ctrl z

5. show voice busyout

DETAILED STEPS

 
Command
Purpose

Step 1 

Router(config)# voice-port slot/subunit/port

Enters voice-port configuration mode for a specified voice port.

Step 2 

Router(config-voiceport)# busyout forced

Places the voice port into the busyout state.

Note If you enter the no busyout forced command, busyout is controlled by the busyout monitor interface command. If you do not enter the busyout monitor interface command, the no busyout forced command forces the voice port out of the busyout state.

Step 3 

Router(config-voiceport)# busyout monitor action graceful

Busies out the voice port immediately if busyout is triggered. If there is an active call on this voice port, the voice port waits until the call is over.

Step 4 

Router(config-voiceport)# Ctrl-Z

Exits the current mode and enters EXEC mode.

Step 5 

router# show voice busyout

Displays the busyout status.

Configuring a Voice Port to Monitor the Link to a Remote Interface

Restrictions

A maximum of 32 network interfaces can be monitored for a voice port.

The maximum number of simultaneous SAA probes is controlled by the SAA subsystem design and its configuration.

Busyout based on monitoring of a remote, IP-addressable interface is not activated when DSP resources and bandwidth are unavailable.

The PSTN Fallback feature must be enabled for the busyout monitor probe command to function. It must also be configured on the router and the SAA responder on the target router.

The SAA responder function must be enabled on the router at the remote IP address targeted by the SAA probe.

The SAA probe feature can be configured on CAS trunks only (not CCS).

If a voice port monitors multiple links, busyout occurs only when all of the monitored links go below the threshold.

You can configure individual voice ports for busyout, or you can apply a voice class that includes all of the busyout parameters (see the "Assigning Voice Classes to Voice Ports" section).


Note If a busyout voice class is already assigned to a voice port, you cannot configure busyout using an SAA probe using this procedure.


SUMMARY STEP

1. voice-port slot/subunit/port

2. busyout monitor probe ip-address [codec codec-type] [icpif number | loss percent delay m s]

3. exit

DETAILED STEP

 
Command
Purpose

Step 1 

Router(config)# voice-port slot/subunit/port

Enters voice-port configuration mode for a specified voice port.

Step 2 

Router(config-voiceport)# busyout monitor probe ip-address [codec codec-type] [icpif number | loss percent delay ms]

Configures the busyout probe that monitors the link to the remote interface identified by an IP address. Reenter the command for each additional interface to be monitored. Keywords and arguments are as follows:

codec-type—(Optional) SAA probe signal.

icpif number—(Optional) Threshold for ICPIF.

loss percent delay—(Optional) Threshold in ms, or loss and delay thresholds individually.

Note If icpif values are not entered, the packet delay values from the call fallback active command are used.

Step 3 

Router(config-voiceport)# exit

Exits the current mode.

Verifying the Voice-Port Busyout Configuration


Step 1 Shut down the remote interface associated with the configured IP address. This busies out the voice port.

Step 2 show voice busyout

Use this command to display information about the busyout state.

The following is sample output for voice ports on a Cisco MC3810:

Router# show voice busyout

Voice port busyout will be triggered by the
following network interfaces states 
 1/1 probe 192.168.202.128 codec g711u icpif 25 
 1/2 probe 192.168.202.128 codec g711u icpif 25 
 1/3 probe 192.168.202.128 codec g711u icpif 25
The following voice ports are in busyout state 

1/1	is in busyout state caused by probe 192.168.202.128 codec g711u icpif 2
1/2	is in busyout state caused by probe 192.168.202.128 codec g711u icpif 2
1/3	is in busyout state caused by probe 192.168.202.128 codec g711u icpif 2


Configuring a Busyout-Monitoring Voice Class

A busyout voice class monitors local ports (serial and Ethernet) and links to remote IP addresses. Busyout occurs when all of the monitored local ports are OOS or when all of the monitored links go below the configured threshold value. If a voice port is configured to monitor multiple links, busyout occurs only when all of the monitored links go below the threshold.

To configure a busyout-monitoring voice class, use the following commands.

SUMMARY STEPS

1. voice class busyout tag

2. busyout monitor serial interface-number [in-service]

3. busyout monitor ethernet interface-number [in-service]

4. busyout monitor probe ip-address [codec codec-type] [icpif number | loss loss-value delay ms]

5. busyout monitor gatekeeper

6. exit

7. voice-port slot/subunit/port

8. voice-class permanent tag

9. exit

DETAILED STEPS

 
Command
Purpose

Step 1 

Router(config)# voice class busyout tag

Enters voice-class configuration mode and creates a voice class for defining busyout conditions. Range for tag: 1 to 10000 (must be unique on the router).

Step 2 

Router(config-class)# busyout monitor serial interface-number [in-service]

(Optional) Specifies a local serial interface to be monitored by the voice port. To configure the voice port to monitor multiple interfaces, reenter the command for each additional interface to be monitored.

Default: the voice port is busied out when the monitored interface is OOS. Enter the keyword in-service to configure the voice port for busyout when the monitored interface comes into service. If a voice port is configured to monitor multiple interfaces for the in-service state, busyout occurs when any one monitored serial or Ethernet interface comes into service.

Step 3 

Router(config-class)# busyout monitor ethernet interface-number [in-service]

(Optional) Specifies a local Ethernet interface to be monitored by the voice port. To configure the voice port to monitor multiple interfaces, reenter the command for each additional interface.

Default: the voice port is busied out when the monitored interface is OOS. Enter the keyword in-service to configure the voice port for busyout when the monitored interface comes into service. If a voice port is configured to monitor multiple interfaces for the in-service state, busyout occurs when any one monitored serial or Ethernet interface comes into service.

Step 4 

Router(config-class)# busyout monitor probe ip-address [codec codec-type] [icpif number | loss loss-value delay ms]

(Optional) Configures the voice port to use an SAA probe to monitor the link to the remote interface identified by an IP address.

Specifies a codec profile for the SAA probe signal and ICPIF loss/delay threshold or loss and delay thresholds individually. Packet loss and delay determine the threshold for initiating the busyout state.

Note To configure the voice port to monitor multiple remote interfaces, reenter the command for each additional interface to be monitored.

If a threshold value is not entered, the packet delay values from the call fallback active command are used.

Note PSTN fallback must be configured on this router and the SAA responder on the target router.

Step 5 

Router(config-class)# busyout monitor gatekeeper

Configures the monitor to trigger a busyout when any voice port assigned to this voice class loses connectivity to the gatekeeper.

Step 6 

Router(config-class)# exit

Exits the current mode.

Step 7 

Router(config)# voice-port slot/subunit/port

Enters voice-port configuration mode for a specified voice port.

Step 8 

Router(config-voiceport)# voice-class permanent 
tag

Assigns the voice class to a voice port. The tag argument is a unique number assigned to the voice class. Range: 1 to 10000.

Note The voice class command in global configuration mode is entered without a hyphen.

Step 9 

Router(config-voiceport)# exit

Exits the current mode.

Repeat Step 6 through Step 8 to assign the voice class for the busyout function to all voice ports that have these busyout requirements.

Verifying the Voice and Voice-Class Busyout Configuration


Step 1 Shut down or bring up the monitored interface or interfaces, as required. The voice port is busied out. Monitored interfaces can be any of the following, depending on the configuration:

Local interfaces—for the busyout monitor serial and the busyout monitor ethernet commands. If the voice port is configured to monitor multiple local interfaces for OOS, busyout occurs only when all the monitored interfaces are OOS. If a voice port is configured to monitor multiple local interfaces for the in-service state, busyout occurs when any one monitored interface comes into service.

Remote interface—for the busyout monitor probe command.

The voice port monitors a remote IP address for OOS only.


Note Ensure that PSTN fallback is configured on the local router and SAA responder is configured on the target router.


Step 2 show voice busyout

Use this command to display information about the busyout state.

The following is sample output for voice ports on a Cisco MC3810:

Router# show voice busyout

Voice port busyout will be triggered by the following network interfaces states 
 1/2 busyout monitor ATM0 
 1/3 busyout monitor ATM0 
 1/4 busyout monitor Serial0 
 1/5 busyout monitor Serial0 
 1/6 probe 192.168.202.128 codec g711u icpif 25
The following voice ports are in busyout state
 
1/1 is forced into busyout state 
1/2 is in busyout state caused by ATM0 
1/3 is in busyout state caused by ATM0 
1/4 is in busyout state caused by Serial0 
1/5 is in busyout state caused by Serial0
1/6 is in busyout state caused by probe 192.168.202.128 codec g711u icpif 2


Configuring a Graceful Busyout

To configure a graceful busyout, use the following commands.

SUMMARY STEPS

1. voice-port slot/subunit/port

2. busyout monitor action graceful

3. exit

DETAILED STEPS

 
Command
Purpose

Step 1 

Router(config)# voice-port slot/subunit/port

Enters voice-port configuration mode for a specified voice port.

Step 2 

Router(config-voiceport)# busyout monitor action graceful

Specifies the use of a graceful busyout. That is, the voice port is busied out immediately when triggered, if there are no active calls. If there is an active call, the voice port waits until the call is over.

Step 3 

Router(config-voiceport)# exit

Exits the current mode.

Configuring Busyout Monitor

Prerequisites


Note For information on the following configuration tasks, see the "Related Documents" section.


Configure VoIP, VoFR, or VoATM, including POTS and network dial peers.

Configure voice ports.

Configure call fallback on the local router.

Configure SAA responder on the target (far-end) router.

SUMMARY STEPS

1. voice-port slot/subunit/port

2. busyout monitor {serial interface-number | ethernet interface-number | fastethernet | interface-number}

3. busyout monitor action graceful

4. exit

DETAILED STEPS

 
Command
Purpose

Step 1 

Router(config)# voice-port slot/subunit/port

Enters voice-port configuration mode for a specified voice card.

Step 2 

Router(config-voiceport)# busyout monitor {serial interface-number | ethernet interface-number | fastethernet | interface-number}

Places a voice port into busyout monitor state. Keywords and arguments are as follows:

serial—Monitoring of a serial interface. More than one interface can be entered for a voice port.

ethernet—Monitoring of an Ethernet interface. More than one interface can be entered for a voice port.

fastethernet—Monitoring of a Fast Ethernet interface. More than one interface can be entered for a voice port.

interface-number—Interface to be monitored for the voice-port busyout function.

Step 3 

Router(config-voiceport)# busyout monitor action graceful

Places a voice port into monitor the need for a graceful busyout. That is, the voice port will be busied out immediately when triggered, if there are no active calls. If there is an active call, the voice port will wait until the call is over.

Step 4 

Router(config-voiceport)# exit

Exits the current mode.

Configuring Busyout Monitor Gatekeeper

To configure a voice port to busy out a voice port if the gateway loses connection to the primary gatekeeper, use the following commands.

SUMMARY STEPS

1. voice-port slot/subunit/port

2. busyout monitor gatekeeper

3. exit

DETAILED STEPS

 
Command
Purpose

Step 1 

Router(config)# voice-port slot/subunit/port

Enters voice-port configuration mode for a specified voice port.

Step 2 

Router(config-voiceport)# busyout monitor gatekeeper

Specifies busyout when connectivity to the gatekeeper is lost.

Step 3 

Router(config-voiceport)# exit

Exits the current mode.

Verifying Busyout Status

To verify that busyout is configured correctly, use the show running-configuration command to display the command settings for the router, as shown in the "Configuring Local and Advanced Voice Busyout" section.

Configuring PSTN Fallback

This section contains the following procedures (each identified as either optional or required):

Configuring Fallback to Alternate Dial Peers (required)

Configuring Destination Monitoring without Fallback to Alternate Dial Peers (optional)

Configuring Call-Fallback Cache Parameters (optional)

Configuring Call-Fallback Jitter-Probe Parameters (optional)

Configuring Call-Fallback Probe-Timeout and Weight Parameters (optional)

Configuring Call-Fallback Threshold Parameters (optional)

Configuring Call-Fallback Wait-Timeout (optional)

Configuring VoIP Alternate Path Fallback SNMP Trap (optional)

Configuring Call-Fallback Map Parameters (optional)

Verifying PSTN Fallback Configuration (optional)

Monitoring and Maintaining PSTN Fallback

Restrictions

When network congestion is detected, the PSTN Fallback feature does not affect existing calls. It affects only subsequent calls.

There can only be one ICPIF/delay-loss value per system.

There is a small additional call setup delay for the first call to a new IP destination.

The PSTN Fallback feature is supported for H.323 VoIP calls only.

Prerequisites


Note For information on the following configuration task, see the "Related Documents" section.


Configure VoIP.

Configuring Fallback to Alternate Dial Peers

To configure fallback to alternate dial peers, use the following commands.

SUMMARY STEPS

1. call fallback active

2. call fallback key-chain name-of-chain

DETAILED STEPS

 
Command
Purpose

Step 1 

Router(config)# call fallback active

Enables the PSTN fallback feature to alternate dial peers in case of network congestion.

Step 2 

Router(config)# call fallback key-chain name-of-chain

Specifies MD5 configuration.

Configuring Destination Monitoring without Fallback to Alternate Dial Peers

To configure destination monitoring without fallback to alternate dial peers, use the following commands.

SUMMARY STEP

call fallback monitor

DETAILED STEP

 
Command
Purpose
 

Router(config)# call fallback monitor

Enables the monitoring of destinations without fallback to alternate dial peers.

Configuring Call-Fallback Cache Parameters

To configure the call-fallback cache parameters, use the following commands.

SUMMARY STEPS

1. call fallback cache-size number

2. call fallback cache-timeout seconds

3. clear call fallback cache [ip-address]

DETAILED STEPS

 
Command
Purpose

Step 1 

Router(config)# call fallback cache-size number

Specifies the call fallback cache size.

Step 2 

Router(config)# call fallback cache-timeout seconds

Specifies the time after which the cache entry is purged, in seconds. Default: 600.

Step 3 

Router# clear call fallback cache [ip-address]

Clears the current ICPIF estimates for all IP addresses or a specific IP address in the cache.

Configuring Call-Fallback Jitter-Probe Parameters

To configure call-fallback jitter-probe parameters, use the following commands.

SUMMARY STEPS

1. call fallback jitter-probe num-packets number-of-packets

2. call fallback jitter-probe precedence precedence
or
call fallback jitter-probe dscp dscp-number

3. call fallback jitter-probe priority-queue

DETAILED STEPS

 
Command
Purpose

Step 1 

Router(config)# call fallback jitter-probe num-packets number-of-packets

Specifies the number of packets for jitter. Default: 15.

Step 2 

Router(config)# call fallback jitter-probe precedence precedence


or

Router(config)# call fallback jitter-probe dscp dscp-number

Specifies the treatment of the jitter-probe transmission. Default: 2.

Specifies the differentiated services code point (dscp) packet of the jitter-probe transmission.

Note The call fallback jitter-probe precedence command is mutually exclusive with the call fallback jitter-probe dscp command. Only one of these command can be enabled on the router. Usually the call fallback jitter-probe precedence command is enabled. When the call fallback jitter-probe dscp command is configured, the precedence value is replaced by the DSCP value. To disable DSCP and restore the default jitter probe precedence value, use the no call fallback jitter-probe dscp command.

Step 3 

Router(config)# call fallback jitter-probe priority-queue

Assigns a priority to the queue for jitter probes.

Configuring Call-Fallback Probe-Timeout and Weight Parameters

To configure call-fallback jitter-probe parameters, use the following commands.

SUMMARY STEPS

1. call fallback probe-timeout seconds

2. call fallback instantaneous-value-weight weight

DETAILED STEPS

 
Command
Purpose

Step 1 

Router(config)# call fallback probe-timeout seconds

Sets the timeout for an SAA probe, in seconds. Default: 30.

Step 2 

Router(config)# call fallback instantaneous-value-weight weight

Configures the call fallback subsystem to take an average from the last two probes registered in the cache for call requests.

Configuring Call-Fallback Threshold Parameters

To configure call-fallback threshold parameters, use the following commands.

SUMMARY STEPS

call fallback threshold delay delay-value loss loss-value

or

call fallback threshold icpif threshold-value

DETAILED STEPS

 
Command
Purpose
 

Router(config)# call fallback threshold delay delay-value loss loss-value

or


Router(config)# call fallback threshold icpif threshold-value

Specifies fallback threshold to use packet delay and loss values. No defaults.

Note The amount of delay set by the call fallback threshold delay loss command should not be more than half the amount of the time-to-wait value set by the call fallback wait-timeout command; otherwise the threshold delay will not work correctly. Because the default value of the call fallback wait-timeout command is set to 300 milliseconds, the user can configure a delay of up to 150 milliseconds for the call fallback threshold delay loss command. If the user wants to configure a higher threshold, the time-to-wait delay has to be increased from its default (300 milliseconds) using the call fallback wait-timeout command.

Specifies fallback threshold to use the Calculated Planning Impairment Factor (ICPIF) threshold for network traffic.

Configuring Call-Fallback Wait-Timeout

To configure the call-fallback wait-timeout parameters, use the following commands:

Summary Steps

call fallback wait-timeout milliseconds

DETAILED STEPS

 
Command
Purpose
 

Router(config)# call fallback wait-timeout milliseconds

Configures the waiting timeout interval for a response to a probe in milliseconds. Default: 300 milliseconds.

The time-to-wait period set by the call fallback wait-timeout command should always be greater than or equal to twice the amount of the threshold delay time set by the call fallback threshold delay loss command; otherwise the probe will fail.

Note The delay configured by the call fallback threshold delay loss command corresponds to a one-way delay, whereas the time-to-wait period configured by the call fallback wait-timeout command corresponds to a round-trip delay. The threshold delay time should be set at half the value of the time-to-wait value.

Configuring VoIP Alternate Path Fallback SNMP Trap

The VoIP Alternate Path Fallback SNMP Trap feature adds a Simple Network Management Protocol (SNMP) trap generation capability. This feature is built on top of the fallback subsystem to provide an SNMP notification trap when the fallback subsystem redirects or rejects a call because a network condition has failed to meet the configured threshold. The SNMP trap provides VoIP management status MIB information without flooding management systems with unnecessary messages about call status by triggering only when a call has been redirected to the public switched telephone network (PSTN) or the alternative IP port. A call can be rejected because of a network problem such as loss of WAN connection, delay, packet loss, or jitter. This feature supports only VoIP signaling protocol with H.323 in this release.

This feature has to be configured on the originating gateway and the terminating gateway. To configure the SNMP trap parameters, use the following commands:

SUMMARY STEPS

1. call fallback active

2. snmp-server enable traps voice fallback

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

call fallback active

Example:

Router(config)# call fallback active

Enables the PSTN fallback feature to alternate dial peers in case of network congestion.

Step 2 

snmp-server enable traps voice fallback

Example:

Router(config)# snmp-server enable traps voice fallback

Enables SNMP fallback notifications.

What to Do Next

Configure the rtr responder command on the terminating voice gateway. If the rtr responder is enabled on the terminating gateway, the terminating gateway responds to the probe request when the originating gateway sends an Response Time Report (RTR) probe to the terminating gateway to check the network conditions. The details on how to configure RTR can be found in the Network Monitoring Using Cisco Service Assurance Agent section of the Cisco IOS Configuration Fundamentals Configuration Guide, Release 12.2.

Configuring Call-Fallback Map Parameters

To configure call-fallback map parameters, use the following commands.

SUMMARY STEPS

call fallback map map target ip-address address-list ip-address1 ip-address2 ... ip-address7

or

call fallback map map target ip-address subnet ip-network netmask

DETAILED STEPS

 
Command
Purpose
 

Router(config)# call fallback map map target ip-address address-list ip-address1 ip-address2 ... ip-address7


or

Router(config)# call fallback map map target ip-address subnet ip-network netmask

Specifies the call fallback router to keep a cache table (by IP addresses) of distances for several destination peers sitting behind the router.

Specifies the call fallback router to keep a cache table (by subnet addresses) of distances for several destination peers sitting behind the router.

Verifying PSTN Fallback Configuration

To verify PSTN Fallback configuration, use the following commands.


Step 1 show running-config

Use this command to display the contents of the currently running configuration file to see if the new feature is configured.

Step 2 show call history voice

Use this command to display the call history table for voice calls and verify call fallback, call delay, and call loss parameters.

Step 3 show call fallback cache

Use this command to display the current Calculated Planning Impairment Factor (ICPIF) estimates for all IP addresses in the call fallback cache.

Step 4 show call fallback config

Use this command to display the current configuration.

Step 5 show call fallback stats

Use this command to display the call fallback statistics.


Monitoring and Maintaining PSTN Fallback

SUMMARY STEPS

1. clear call fallback cache

2. clear call fallback stats

3. debug call fallback detail

4. debug call fallback probes

5. test call fallback probe ip-address

6. debug snmp packets

DETAILED STEPS

 
Command
Purpose

Step 1 

Router# clear call fallback cache

(Optional) Clears the current ICPIF estimates for all IP addresses in the cache.

Step 2 

Router# clear call fallback stats

(Optional) Clears the call fallback statistics.

Step 3 

Router# debug call fallback detail

(Optional) Displays details of VoIP call fallback.

Step 4 

Router# debug call fallback probes

(Optional) Displays details of voice fallback probes.

Step 5 

Router# test call fallback probe ip-address

(Optional) Tests a probe to a particular IP address and displays the ICPIF SAA values.

Step 6 

Router# debug snmp packets

(Optional) Displays information about every Simple Network Management Protocol (SNMP) packet sent or received by the router.

Configuration Examples for Trunk Monitoring and Management

This section provides the following configuration examples:

Analog Centralized Automatic Message Accounting E911 Trunk: Examples

Busyout: Examples

Local Voice Busyout Configuration: Examples

Alarm Trigger for Busyout of Voice Ports Configuration: Example

Call Admission Control: Examples

Call Admission Control for H.323 VoIP Gateways: Examples

MGCP VoIP Call Admission Control: Examples

PSTN Fallback: Examples

Analog Centralized Automatic Message Accounting E911 Trunk: Examples

VIC-2CAMA for CAMA Signaling

The following example shows that the VIC-2CAMA is configured for 8-digit transmission:

!
voice-port 1/0/0
 timing digit 75
 timing inter-digit 65
 ani mapping 0 408
 ani mapping 1 510
 ani mapping 2 610
 ani mapping 3 710
 signal cama KP-NPD-NXX-XXXX-ST
!
voice-port 1/0/1
 timing digit 75
 timing inter-digit 65
 ani mapping 0 408
 ani mapping 1 510
 ani mapping 2 610
 ani mapping 3 710
 signal cama KP-NPD-NXX-XXXX-ST
!

ANI Mapping

The following example shows port 0 and port 1 with the Numbering Plan Area (NPA), or area code, preprogrammed into a single MF digit. The Numbering Plan Digit (NPD) table is preprogrammed in the sending and receiving equipment on each end of the MF trunk. Configuration of only one port is necessary, because both ports are configured simultaneously.

The following example shows configuration for the following NPAs (area codes): 0=408, 1=510, 2=610, 3=710.

!
voice-port 1/0/0
 timing digit 75
 timing inter-digit 65
 ani mapping 0 408
 ani mapping 1 510
 ani mapping 2 610
 ani mapping 3 710
 signal cama KP-NPD-NXX-XXXX-ST
!
voice-port 1/0/1
 timing digit 75
 timing inter-digit 65
 ani mapping 0 408
 ani mapping 1 510
 ani mapping 2 610
 ani mapping 3 710
 signal cama KP-NPD-NXX-XXXX-ST
!

Busyout: Examples

This section provides the following configuration examples:

Local Voice Busyout Configuration: Examples

Alarm Trigger for Busyout of Voice Ports Configuration: Example

Local Voice Busyout Configuration: Examples

The following example configures digital voice port 0:0.4 on a Cisco MC3810 series to go into the busyout state if serial interface 0:0 goes out of service:

Router(config)# voice-port 0:0.4

  Type of VoicePort is FXS
router(config-voiceport)# busyout monitor interface serial 0:0
1/2 is in busyout state

Router(config-voiceport)# end
Router# show voice busyout

!If following network interfaces are down, voice port will be put into busyout state
The following voice ports are in busyout state

1/1 is forced into busyout state
1/2 is in busyout state caused by Serial0

The following example configures digital voice port 2/1:7 on a Cisco 3600 series to go into the busyout state if serial interface 0:0 goes out of service:

Router(config)# voice-port 2/1:7

  Type of VoicePort is FXS

Router(config-voiceport)# busyout monitor interface serial 0:0

1/2 is in busyout state

Router(config-voiceport)# end
Router# show voice busyout

!If following network interfaces are down, voice port will be put into busyout state
The following voice ports are in busyout state

2/1:7 is forced into busyout state
2/1:8 is in busyout state caused by Serial0

The following example configures the busyout seize action for analog voice port 0/2/1 on a Cisco 3600 series to repeat:

Router(config)# voice-port 0/2/1

  Type of VoicePort is FXO

Router(config-voiceport)# busyout seize repeat
Router(config-voiceport)# end
Router# show voice busyout

!If following network interfaces are down, voice port will be put into busyout state
The following voice ports are in busyout state

0/2/1 is forced into busyout state
0/2/2 is in busyout state caused by Serial0

The following example forces DS0 timeslots 1 through 12 on controller T1 0 on a Cisco MC3810 into the busyout state:

Router(config)# controller t1 0
Router(config-controller)# ds0 busyout 1-12
Router(config-controller)# end

The following example configures busyout voice class 35, which initiates voice-port busyout whenever either serial port 0 or 1 is in service, and it applies voice class 35 to voice port 1/3:

Router(config)# voice class busyout 35
Router(config-class)# busyout monitor serial 0 in-service
Router(config-class)# busyout monitor serial 1 in-service
Router(config-class)# exit
Router(config)# voice-port 1/3
Router(config-voiceport)# voice class 35

The following example configures busyout voice class 40, which initiates voice-port busyout whenever an SAA probe sent to both of the two specified remote interfaces results in a link with an ICPIF delay/loss average of more than 15, and it applies voice class 40 to voice port 1/4:

Router(config)# voice class busyout 40
Router(config-class)# busyout monitor probe 192.168.202.128 icpif 15
Router(config-class)# busyout monitor probe 192.168.202.129 icpif 15
Router(config-class)# exit
Router(config)# voice-port 1/4
Router(config-voiceport)# voice class 40

The following example configures analog voice port 1/1 on a Cisco MC3810 to use an SAA probe with a G.711 alaw profile to probe the link to the remote interface with IP address 192.168.202.128, and to busyout the voice port if the link has a packet loss of more than 50 percent and a packet delay of more than 25 ms:

Router(config)# voice-port 1/1
Router(config-voiceport)# busyout monitor probe 192.168.202.128 codec g711a loss 50 
delay 25

The following example configures voice port 1/0/1 on a Cisco 3600 series to use an SAA probe with the default (G.711 ulaw) profile to probe the link to the remote interface with IP address 192.168.202.128, and to busyout the voice port if the link has packet loss and delay that exceed the threshold values configured by the call fallback active command:

Router(config)# voice-port 1/0/1
Router(config-voiceport)# busyout monitor probe 192.168.202.128

The following example configures busyout voice class 60, which configures multiple parameters for voice-port busyout, and it applies voice class 60 to voice ports 1/0/0 and 1/0/1 on a Cisco 3600 series. The voice ports busy out under any one the following conditions:

Serial ports 0/0 and 0/1 are both OOS

Serial port 1/0 or 1/0 is in service

The link loss exceeds 50 percent or the link delay exceeds 1 second on the links to both remote interfaces (IP addresses 192.168.202.128 and 192.168.202.129)

Router(config)# voice class busyout 60
Router(config-class)# busyout monitor serial 0/0
Router(config-class)# busyout monitor serial 0/1
Router(config-class)# busyout monitor serial 1/0 in-service
Router(config-class)# busyout monitor serial 1/1 in-service
Router(config-class)# busyout monitor probe 192.168.202.128 loss 50 delay 1000
Router(config-class)# busyout monitor probe 192.168.202.129 loss 50 delay 1000
Router(config-class)# exit
Router(config)# voice-port 1/0/0
Router(config-voiceport)# voice class 60
Router(config-voiceport)# exit
Router(config)# voice-port 1/0/1
Router(config-voiceport)# voice class 60
Router(config-voiceport)# exit

The following example configures voice port 1/1 into forced busyout state:

Router(config)# voice-port 1/1

Type of VoicePort is FXS

Router(config-voiceport)# busyout forced 
00:09:46: port 0 is forced into busyout state 

Router(config-voiceport)# end
Router# show voice busyout

!If following network interfaces are down, voice port will be put into busyout state.
The following voice ports are in busyout state
1/1 is forced into busyout state

The following example configures voice port 1/2 to busyout monitor mode, monitoring serial 0:

Router(config)# voice-port 1/2
Type of VoicePort is FXS

Router(config-voiceport)# busyout-monitor serial 0
1/2 is in busyout state

Router(config-voiceport)# end
Router# show voice busyout

!If following network interfaces are down, voice port will be put into busyout state.
The following voice ports are in busyout state
1/1 is forced into busyout state
1/2 is in busyout state caused by Serial0

The following example configures voice port 1/3 to the busyout seize repeat state:

Router(config)# voice-port 1/3
Type of VoicePort is FXO

router(config-voiceport)# busyout-seize repeat
Router(config-voiceport)# end
Router# show voice busyout

!If following network interfaces are down, voice port will be put into busyout state.
The following voice ports are in busyout state
1/1 is forced into busyout state
1/2 is in busyout state caused by Serial0

The following is a sample configuration of the busyout monitor action graceful and busyout monitor gatekeeper commands:

Router# show running-configuration
Building configuration...

Current configuration :2143 bytes
!
version 12.2
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname 2600a
!
enable secret 5 $1$QHAX$W3J2KNkDTkB99UmLZ7rq9.
enable password xxx
!
username user password 0 passwd
ip subnet-zero
no ip routing
!
!
no ip domain-lookup
!
!
fax interface-type fax-mail
mta receive maximum-recipients 0
!         
controller T1 0/2
 framing sf
 linecode ami
!
!
interface Ethernet0/0
 ip address 10.4.170.95 255.255.255.0
 no ip route-cache
 no ip mroute-cache
 half-duplex
 h323-gateway voip interface
 h323-gateway voip id test ipaddr 10.4.170.77 1719
 h323-gateway voip h323-id morpheus
!
interface Serial0/0
 no ip address
 no ip route-cache
 no ip mroute-cache
 shutdown
 no fair-queue
!
interface Serial0/1
 no ip address
 no ip route-cache
 no ip mroute-cache
 shutdown
!
ip local pool setup_pool 1.2.71.1 1.2.71.255
ip default-gateway 1.2.0.1
ip classless
no ip http server
ip pim bidir-enable
!
!
dialer-list 1 protocol ip permit
dialer-list 1 protocol ipx permit
!
!
snmp-server community public RO
!
voice-port 1/0/0
 type 5
!
voice-port 1/0/1
 type 5
!
voice-port 1/1/0
!
voice-port 1/1/1
 busyout monitor action graceful
 busyout monitor gatekeeper
 busyout monitor Ethernet0/0
!
mgcp
mgcp default-package dtmf-package
!
mgcp profile default
!
dial-peer cor custom
!
!
dial-peer voice 1 voip
 incoming called-number 308
 destination-pattern ...
 session protocol sipv2
 session target ipv4:10.4.170.77
 codec g711ulaw
!
dial-peer voice 2 pots
 destination-pattern 308
 port 1/1/0
 prefix 308
!
dial-peer voice 3 pots
 destination-pattern 309
 port 1/1/1
!
dial-peer voice 4 pots
 application mgcpapp
!
dial-peer voice 7 pots
 application sdfjsadf
!
dial-peer voice 88 pots
!
dial-peer voice 33 voip
 fax rate 12000
!
dial-peer voice 34 voatm
!
dial-peer voice 35 vofr
!
dial-peer voice 37 pots
!
dial-peer voice 90 voatm
!
dial-peer voice 91 voip
 fax rate 4800 bytes 41
!
dial-peer voice 92 vofr
!
dial-peer voice 999 voip
 destination-pattern 1234
 session target ras
!
gateway
!
!
line con 0
 exec-timeout 0 0
line aux 0
line vty 0 4
 password lab
 login
line vty 5 15
 login
!
!
end

Alarm Trigger for Busyout of Voice Ports Configuration: Example

This example creates three permanent trunks on controller T1 0 and configures T1 0 to send a blue (AIS) alarm if all three permanent trunks are OOS. These steps create the voice ports and configure the alarm trigger:

Router(config)# controller t1 0
Router(config-controller)# mode cas
Router(config-controller)# ds0-group 0 timeslots 1-10 type fxs-ground-start
Router(config-controller)# ds0-group 1 timeslots 11 type fxs-ground-start
Router(config-controller)# ds0-group 2 timeslots 12-23 type fxs-ground-start
Router(config-controller)# alarm-trigger blue 0-2
Router(config-controller)# exit
Router(config)#

These steps create a voice class to define the trunk conditioning parameters for permanent trunks (in which the default values are not used):

Router(config)# voice class permanent 8
Router(config-class)# signal keepalive 10
Router(config-class)# signal timing oos timeout 60
Router(config-class)# signal timing idle suppress-voice 5
Router(config-class)# signal timing oos restart 120
Router(config-class)# exit
Router(config)#

These steps create a VoIP dial peer to define the network connectivity and trunk conditioning parameters for permanent trunks:

Router(config)# dial-peer voice 100 voip
Router(config-dial-peer)# session target ipv4:172.20.10.10
Router(config-dial-peer)# destination-pattern 10..
Router(config-dial-peer)# voice-class permanent 8
Router(config-dial-peer)# exit
Router(config)#

These steps assign each voice port to a permanent trunk and associate each trunk with a network dial peer:

Router(config)# voice-port 0:0
Router(config-voiceport)# connection trunk 1001
Router(config-voiceport)# exit
Router(config)# voice-port 0:1
Router(config-voiceport)# connection trunk 1002
Router(config-voiceport)# exit
Router(config)# voice-port 0:2
Router(config-voiceport)# connection trunk 1003
Router(config-voiceport)# exit
Router(config)#

This example configures voice port 0:0 for busyout if serial port 0.1, 0.2, and Ethernet port 0 all go out of service, or serial port 1 comes into service:

Router(config)# voice-port 0:0
Router(config-voiceport)# busyout monitor serial 0.1
Router(config-voiceport)# busyout monitor serial 0.2
Router(config-voiceport)# busyout monitor ethernet 0
Router(config-voiceport)# busyout monitor serial 1 in-service
Router(config-voiceport)# exit

This example configures voice port 0:1 for busyout if the connections to both of two remote IP addresses are OOS:

Router(config)# voice-port 0:1
Router(config-voiceport)# busyout monitor probe 192.168.202.128 codec g711a icpif 15
Router(config-voiceport)# busyout monitor probe 192.168.202.129 codec g711a icpif 15
Router(config-voiceport)# exit

This example configures voice port 0:2 for busyout under any one of the following conditions:

Serial port 0.1 and 0.2 are both OOS

Serial port 1 comes into service

Connections to both of two remote IP addresses are OOS

Router(config)# voice-port 0:2
Router(config-voiceport)# busyout monitor serial 0.1
Router(config-voiceport)# busyout monitor serial 0.2
Router(config-voiceport)# busyout monitor serial 1 in-service
Router(config-voiceport)# busyout monitor probe 192.168.202.128 codec g711a icpif 15
Router(config-voiceport)# busyout monitor probe 192.168.202.129 codec g711a icpif 15
Router(config-voiceport)# exit
Router(config)# exit

Call Admission Control: Examples

This section provides the following configuration examples:

Call Admission Control for H.323 VoIP Gateways: Examples

MGCP VoIP Call Admission Control: Examples

Call Admission Control for H.323 VoIP Gateways: Examples

Call Spike Configuration

The following configuration of the call spike command has a call number of 30, 10 steps, and a step size of 2000 ms:

call threshold global cpu-avg low 70 high 80
call spike 30 steps 10 size 2000
cns event-service server

Call Threshold Configuration

The following example busies out the total-calls resource of 5 (low) or 5000 (high):

call threshold global total-calls low 5 high 5000 busyout

The following example enables thresholds of 5 (low) and 2500 (high) on Ethernet interface 0:

call threshold interface Ethernet 0 int-calls low 5 high 2500

The following example busies out the average CPU utilization if 5 percent (low) or 65 percent (high) is reached:

call threshold global cpu-avg low 5 high 65 busyout

Call Threshold Poll Interval Configuration

The following example enables a polling interval threshold for memory of 10 seconds:

call threshold poll-interval memory 10

The following example enables a polling interval threshold of 50 seconds:

call threshold poll-interval cpu-average 50

Call Treatment Configuration

The following example enables the Call Treatment feature with a "hairpin" action:

call treatment on
call treatment action hairpin

The following example displays proper formatting of the action playmsg keywords:

call treatment on
call treatment action playmsg tftp://keyer/prompts/congestion.au


Note The congestion.au file plays when local resources are not available to handle the call.


The following example configures a call treatment cause code to display no-qos when local resources are unavailable to process a call:

call treatment on
call treatment cause-code no-qos

MGCP VoIP Call Admission Control: Examples

MGCP RSVP and SA Agent CAC

The following example shows a configuration of MGCP RSVP and SA Agent CAC on a Cisco 3660:

version 12.2
no service single-slot-reload-enable
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname host1
!
no logging buffered
no logging buffered
logging rate-limit console 10 except errors
!
!
ip subnet-zero
!
!
no ip finger
no ip domain-lookup
ip host lab 192.168.254.254
!
call fallback active
call rsvp-sync
!
!
interface FastEthernet0/0
 ip address 172.16.125.4 255.255.0.0
 duplex auto
 speed auto
 ip rsvp bandwidth 512 512
!
interface FastEthernet0/1
 no ip address
 shutdown
 duplex auto
 speed auto
!
ip kerberos source-interface any
ip classless
ip route 172.16.173.1 255.255.255.255 172.16.0.1
ip route 192.168.254.254 255.255.255.255 FastEthernet0/0
no ip http server
!
!
voice-port 1/1/0
!
voice-port 1/1/1
!
mgcp
mgcp call-agent 172.16.173.1 service-type mgcp version 1.0
mgcp modem passthrough voip mode nse
mgcp modem passthrough voaal2 mode
mgcp rtrcac
no mgcp timer receive-rtcp
!
mgcp profile default
!
dial-peer cor custom
!
!
dial-peer voice 1 pots
 application mgcpapp
 port 1/1/0
!
dial-peer voice 2 pots
 application mgcpapp
 port 1/1/1

rtr responder
!
line con 0
 transport input none
line aux 0
line vty 0 4
 login
!
end

MGCP VoIP CAC on a Trunking Gateway

This configuration enables all three types of MGCP VoIP CAC: SRC, RSVP, and SA Agent. Comment lines are provided above the CAC commands to help you identify the commands needed for a particular CAC type.

version 12.2
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname host1
!
!
voice-card 2
!
voice-card 3
!
ip subnet-zero
ip dhcp smart-relay
!
! The following command is used in MGCP SA Agent CAC.
call fallback active
! The following command is used in MGCP RSVP CAC.
call rsvp-sync
! The following six commands are used in MGCP SRC CAC.
call threshold global cpu-5sec low 55 high 70 treatment
call threshold global cpu-avg low 70 high 80 treatment
call threshold global total-mem low 70 high 80 treatment
call threshold global io-mem low 70 high 80 treatment
call threshold global proc-mem low 70 high 80 treatment
call threshold global total-calls low 10 high 12 treatment
!
!
controller T1 2/0
!
controller T1 2/1
!
controller T1 3/0
 framing esf
 clock source internal
 ds0-group 1 timeslots 1-5 type none service mgcp
 ds0-group 2 timeslots 6-24 type none service mgcp
!
controller T1 3/1
 framing esf
 ds0-group 1 timeslots 1-10 type none service mgcp
 ds0-group 2 timeslots 11-24 type none service mgcp
!
!
interface FastEthernet0/0
 ip address 192.168.1.61 255.255.255.0
 duplex auto
 speed auto
! The following command is used in MGCP RSVP CAC to configure the bandwidth allocated
! for VoIP calls through the interface.
 ip rsvp bandwidth 512 512
!
interface FastEthernet0/1
 ip address 172.20.1.1 255.255.0.0
 duplex auto
 speed auto
!
ip kerberos source-interface any
ip classless
ip route 10.0.0.0 10.0.0.0 192.168.1.10
no ip http server
!
snmp-server engineID local 0000000902000002B95D89F0
no snmp-server ifindex persist
snmp-server manager
!
voice-port 3/0:1
!
voice-port 3/0:2
!
voice-port 3/1:1
!
voice-port 3/1:2
!
mgcp
mgcp call-agent 10.13.57.88 service-type mgcp version 1.0
mgcp modem passthrough voip mode nse
mgcp modem passthrough voaal2 mode
mgcp package-capability trunk-package
! The following command is used for MGCP SA Agent CAC.
 mgcp rtrcac
! The following command is used in MGCP SRC CAC.
mgcp src-cac
no mgcp timer receive-rtcp
!
mgcp profile default
!
dial-peer cor custom
!
dial-peer voice 1 pots