Table of Contents

Feature Overview

Benefits
Restrictions
Related Documents

Supported Platforms
Supported Standards, MIBs, and RFCs
Prerequisites
Configuration Tasks

Configuring Dial Peer Digit Manipulation
Configuring Dial Peer Hunting
Disabling Dial-Peer Hunting on a Specific Dial Peer
Configuring Voice over Frame Relay Connections

Overview of Voice over Frame Relay Connection Types

Configuring Switched Calls (User Dialed or Auto-Ringdown)

Configuring Switched Calls to Other Voice over Frame Relay Routers
Configuring Switched Calls to a Cisco MC3810 Running Cisco IOS Releases Before 12.1(2)T

Configuring Cisco-Trunk Permanent (Private Line) Calls

Configuring Voice over Frame Relay Dial Peers for Cisco-Trunk (Private Line) Calls
Configuring Cisco Trunk Permanent Calls
Configuring Cisco Trunk Permanent Calls to a Cisco MC3810 Running Cisco IOS Releases Before 12.1(2)T

Configuring FRF.11 Trunk (Private Line) Calls
Configuring Connections for Tandem Nodes
Verifying Your Voice Connections
Troubleshooting Tips

Configuration Examples

Two Routers Using Frame Relay Fragmentation
Two Routers Using a VoFR PVC
Router Using a VoFR PVC to a Cisco MC3810 Running Cisco IOS Releases Before 12.1(2)T
Cisco-Trunk (Private Line) Calls Between Two Routers
FRF.11 Trunk Calls Between Two Routers
Tandem Configuration with Three Routers for Switched Calls
Tandem Configuration with a Cisco MC3810 Tandem Node for Switched Calls
Tandem Configuration with a Cisco MC3810 Endpoint Node for Cisco-Trunk (Private Line) Calls
Tandem Configuration with All Cisco MC3810 Concentrators for Switched Calls
Cisco Trunk Call with Hunt Groups

Command Reference
dial-peer hunt
dial-peer terminator
dial-peer voice
forward-digits
frag-pre-queuing
frame-relay interface-dlci
huntstop
signal-type
vofr
voice hunt user-busy
Debug Commands
debug ccfrf11 session
debug ccswvoice vofr-debug
debug ccswvoice vofr-session
debug vtsp vofr subframe
Glossary

Voice over Frame Relay Using FRF.11 and FRF.12 Configuration Updates

Feature Overview

Voice over Frame Relay functionality has been updated in this release, so that configuration on all supported platforms is nearly identical. In Cisco IOS Release 12.0(4)T, when support for Voice over Frame Relay Using FRF.11 and FRF.12 was introduced, configuration procedures were different depending on the router platform used.

Some commands introduced in earlier Cisco IOS releases have been removed or modified. This document describes the configuration procedures effective in this release.

In addition, this release provides support for digital voice calls for Voice over Frame Relay on the Cisco 2600 and 3600 series routers. In previous releases, the Cisco 2600 and 3600 series only supported analog voice calls for Voice over Frame Relay.

Benefits

Configuration Consistency Across All Voice over Frame Relay Routers

This feature provides consistency for configuration requirements across the hardware models that support Voice over Frame Relay: the Cisco 2600 and 3600 series routers, the Cisco 7200 series routers, and the Cisco MC3810 multiservice access concentrator. In previous releases, configuration procedures on the Cisco MC3810 were different from those on other routers.

Digital Voice Support on the Cisco 2600 and 3600 Series Routers

Beginning in this release, the Cisco 3600 series routers support digital voice calls for Voice over Frame Relay. This feature requires that a Digital T1 Packet Voice Trunk network module is installed on the router.

Restrictions

• The Cisco 2600 series and 3600 series routers cannot terminate calls initiated by a Cisco MC3810 using VoFR implementations before Cisco IOS Release 12.0(3)XG or 12.0(4)T.

• Cisco MC3810 concentrators running Cisco IOS Releases before release 12.0(3)XG or 12.0(4)T cannot tandem VoFR calls from Cisco 2600 series, 3600 series, and 7200 series routers.

• It is currently not possible to translate from the VoIP transport protocol to other protocols, such as VoFR. As a result, a call coming in on a VoIP connection is not (tandem) switched to a VoFR connection.

• Hookflash for dial tone recall from the router is not supported. However, the router can pass-through hookflash on FXO-FXS permanent connections and E&M-E&M connections by using the connection trunk voice-port configuration command.

• Voice over ATM Switched Virtual Circuits (SVCs) are not supported in this release.

Caution Voice over ATM SVCs were first supported on the Cisco MC3810 in Cisco IOS Release 12.0(5)XK and 12.0(7)T. If upgrading a Cisco MC3810 from Cisco IOS Release 12.0(5)XK or 12.0(7)T to this release to obtain Voice over Frame Relay improvements, you lose support for your Voice over ATM SVCs.

Related Documents

For complete information about Voice over Frame Relay configuration, see the Cisco IOS Multiservice Applications Configuration Guide, for Cisco IOS Release 12.1.

• For information about voice port changes in Cisco IOS Release 12.1(2)T, see the following
  Cisco IOS 12.1(2)T online documents:

  • Voice Port Enhancements in Cisco 2600 and 3600 Series Routers and MC3810 Series Concentrators

  • Voice Port Testing Enhancements in Cisco 2600 and 3600 Series Routers and MC3810 Series Concentrators

  • Voice Busyout Enhancements on the Cisco 2600 and 3600 Series Routers and MC3810 Series Concentrators

• For information about software configuration requirements for the Digital T1 Packet Voice trunk network modules on the Cisco 2600 and Cisco 3600 series routers, refer to the Cisco IOS 12.1(2)T online document Configuring Digital T1 Packet Voice Trunk Network Modules on Cisco 2600 and 3600 Series Routers.

• For more information about voice technologies, refer to the Cisco IOS Multiservice Applications Configuration Guide, and the Cisco IOS Multiservice Command Reference, for
  Cisco IOS Release 12.1.

Supported Platforms

• Cisco 2600

• Cisco 3600

• Cisco MC3810

• Cisco 7200

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Note In Cisco IOS releases before release 12.0(5)XE, the Cisco 7200 series routers could only act as a tandem router in Voice over Frame Relay topologies and could not terminate VoFR calls. Beginning in Cisco IOS Release 12.0(5)XE2 and 12.1(1)T, the Cisco 7200 series routers can terminate VoFR calls.

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Supported Standards, MIBs, and RFCs

Standards

None

MIBs

None

For descriptions of supported MIBs and how to use MIBs, see the Cisco MIB web site on CCO at http://www.cisco.com/public/sw-center/netmgmt/cmtk/mibs.shtml.

RFCs

None

Prerequisites

Before you can configure a Cisco router to use Voice over Frame Relay, you must do the following:

Configuration Tasks

This section describes the following new and modified configuration procedures for Voice over Frame Relay in this release:

• Configuring Dial Peer Digit Manipulation (Required)

• Configuring Dial Peer Hunting (Required)

• Configuring Voice over Frame Relay Connections

For all remaining Voice over Frame Relay procedures, see the "Configuring Voice over Frame Relay" chapter in Cisco IOS Multiservice Applications Configuration Guide for Cisco IOS Release 12.1.

Configuring Dial Peer Digit Manipulation

In Cisco IOS Release 12.1(2)T, the forward-digits command used for POTS dial-peer digit manipulation has been changed. To configure dial-peer digit manipulation to forward digits, perform the following steps beginning in global configuration mode:

	Command	Purpose
Step 1	Router(config)# dial-peer voice tag pots	Enter dial-peer configuration mode for a POTS dial peer.
Step 2	Router(config-dial-peer)# forward-digits {num-digit | all | extra} or Router(config-dial-peer)# default forward-digits or Router(config-dial-peer)# no forward-digits	If using the forward-digits feature, configure the digit-forwarding method. The range for the number of digits forwarded (num-digit) is 0 through 32. See the "Command Reference" section for an explanation of the command options. In the default condition, dialed digits not matching the destination pattern are forwarded. Note The no state is not the default state.

Configuring Dial Peer Hunting

After you have configured dial peers, you can configure how the router performs dial peer hunting functions. To configure the dial peer hunting behavior on the router, perform the following steps beginning in configuration mode:

	Command	Purpose
Step 1	Router(config)# dial-peer hunt hunt-order-number	Specify the hunt selection order for dial peers.
Step 2	Router(config)# dial-peer terminator character	(Optional) Designate a special character to be used as a terminator for variable-length dialed numbers.

Disabling Dial-Peer Hunting on a Specific Dial Peer

If using dial-peer hunting, there may be situations when you want to disable dial-peer hunting on a specific dial peer. To disable dial-peer hunting on a dial peer, use the following commands beginning in global configuration mode:

	Command	Purpose
Step 1	Router(config)# dial-peer voice tag {pots | vofr}	Enter dial-peer configuration mode for the specified dial peer.
Step 2	Router(config-dial-peer)# huntstop	Disable dial-peer hunting on the dial peer. Once you enter this command, no further hunting is allowed if a call fails on the specified dial peer.

To reenable dial-peer hunting on a dial peer, enter the no huntstop command.

Configuring Voice over Frame Relay Connections

After you have configured the Frame Relay DLCI settings and you have configured your dial plan, you are ready to configure specific VoFR connections.

There are many different scenarios for VoFR connections. For information on the different connection types, see the next section, "Overview of Voice over Frame Relay Connection Types."

For procedures on how to configure the different connection types, see the following sections:

• Configuring Switched Calls (User Dialed or Auto-Ringdown)

• Configuring Cisco-Trunk Permanent (Private Line) Calls

• Configuring FRF.11 Trunk (Private Line) Calls

In addition, special consideration is required for configuring calls for tandem nodes. For more information, see the "Configuring Connections for Tandem Nodes" section.

Note Use of Cisco trunks for permanent calls (private-line) is recommended over FRF.11 trunk calls unless FRF.11 compliant standards-based interworking is required with non-Cisco devices. The Cisco trunk protocol is a superset of the FRF.11 protocol and contains Cisco proprietary extensions designed to support switched call routing and other advanced features.

Overview of Voice over Frame Relay Connection Types

When you configure VoFR connections, you can use many different connection types depending on the hardware platform, whether the call is to be a regular switched (user dialed or auto-ringdown) call, or whether the call is a permanent call (Cisco-trunk or FRF.11-trunk). You configure these specific connection types by using combinations of several commands.

Table 1 lists the different connection types for VoFR connections supported on the Cisco 2600 and 3600 series routers, and the combinations of commands to enter for each call type.

Note Calls to Cisco MC3810 concentrators running Cisco IOS releases before 12.0(7)XK and 12.1(2)T require different commands. Specific procedures for this configuration are described in separate sections.

Table 1: Voice over Frame Relay Connection Types that are Supported

Type of Call	Frame Relay DLCI Interface Command to Enter1	Data Fragmentation Supported by VoFR Command	Session Protocol Command to Enter in Dial-Peer mode	Voice Port Connection Command to Enter
Switched call (user dialed or auto-ringdown) to other routers supporting VoFR	vofr [data cid] [call-control [cid]]2	FRF.11 Annex C	session protocol cisco-switched3	For user dialed calls: none For auto-ringdown calls: connection plar destination-string
Switched call (user dialed or auto-ringdown) to a Cisco MC3810 running Cisco IOS Releases before 12.1(2)T	vofr cisco4	Cisco  proprietary5	session protocol cisco-switched	For user dialed calls: none For auto-ringdown calls: connection plar destination-string
Cisco-trunk permanent call (private-line) to other routers supporting VoFR	vofr data cid call-control cid	FRF.11 Annex C	session protocol cisco-switched	connection trunk destination-string [answer mode]
Cisco-trunk permanent call (private-line) to a Cisco MC3810 running Cisco IOS Releases before 12.1(2)T	vofr cisco	Cisco proprietary	session protocol cisco-switched	connection trunk destination-string [answer mode]
FRF.11 trunk call (private-line) to other routers supporting VoFR	vofr [data cid] [call-control cid]6	FRF.11 Annex C	session protocol frf11-trunk	connection trunk destination-string [answer mode]

1The voice-encap option of the frame-relay interface-dlci command on the Cisco MC3810 is no longer supported as of Cisco IOS Release 12.1(2)T. 2The recommended use of this command is vofr data 4 call-control 5. 3The session protocol cisco-switched option is the default setting. If you do not enter this command, the setting still applies. 4This command consumes data CID 4 and call-control CID 5. 5Cisco proprietary fragmentation is based on an early draft of FRF.12 and is compatible with Cisco MC3810 concentrators running software releases before Cisco IOS Release 12.0(3)XG or 12.0(4)T. 6For FRF.111 trunk calls, the call-control option is not required. It is only required if you mix FRF.11 trunk calls with other types of voice calls on the same PVC.

Configuring Switched Calls (User Dialed or Auto-Ringdown)

This section describes how to configure switched calls (user dialed or auto-ringdown) on the different router platforms. This section is divided into the following procedures:

• Configuring Switched Calls to Other Voice over Frame Relay Routers

• Configuring Switched Calls to a Cisco MC3810 Running Cisco IOS Releases Before 12.1(2)T

Configuring Switched Calls to Other Voice over Frame Relay Routers

You can configure switched calls on Cisco 2600, 3600, and 7200 series routers, and on Cisco MC3810 concentrators.

Note If you are configuring switched calls to Cisco MC3810 concentrators running Cisco IOS releases before 12.1(2)T, see "Configuring Switched Calls to a Cisco MC3810 Running Cisco IOS Releases Before 12.1(2)T" section.

To configure switched calls on routers that support VoFR, use the following commands from interface configuration mode:

	Command	Purpose
Step 1	Router(config-if)# frame-relay interface-dlci dlci	Configure the Frame Relay DLCI and enter DLCI configuration mode.
Step 2	Router(config-if)# vofr [data cid] [call-control [cid]]	Configure the Frame Relay DLCI to support VoFR and set the data and call-control CIDs. The recommended setting for this command is vofr data 4 call-control 5. Note When the vofr command is used, all subchannels on the DLCI are configured for FRF.11 encapsulation. If you enter the vofr command without any keywords or arguments, the data subchannel is CID 4 and there is no call-control subchannel. If you are configuring user-dialed calls, this procedure is completed. If you are configuring auto-ringdown calls, proceed to the next step.
Step 3	For Cisco 2600 and 3600 series analog voice ports: Router(config)# voice-port slot/subunit/port For Cisco 2600 and 3600 series digital voice ports: Router(config)# voice-port slot/port:ds0-group For Cisco MC3810 series analog voice ports: Router(config)# voice-port slot/port For Cisco MC3810 series digital voice ports: Router(config)# voice-port slot:ds0-group	Identify the voice port you want to configure and enter voice-port configuration mode.
Step 4	Router(config-voiceport)# connection plar destination-string	(Optional) For auto-ringdown calls, configure the PLAR connection, specifying the telephone number in the destination-string.

This configuration uses standard FRF.11 Annex C fragmentation.

Configuring Switched Calls to a Cisco MC3810 Running Cisco IOS Releases Before 12.1(2)T

You can configure switched calls to Cisco MC3810 concentrators running Cisco IOS releases before 12.1(2)T. However, the configuration is different from standard switched calls because earlier Cisco MC3810 releases used the Cisco proprietary version of FRF.12.

Note The Cisco 2600/3600 series routers cannot terminate or initiate calls with a Cisco MC3810 running software releases before Cisco IOS Releases 12.0(3)XG and 12.0(4)T.

To configure switched calls to a Cisco MC3810 running Cisco IOS releases before 12.1(2)T, use the following commands beginning in interface configuration mode:

	Command	Purpose
Step 1	Router(config-if)# frame-relay interface-dlci dlci	Configure the Frame Relay DLCI and enter DLCI configuration mode. Note The voice-encap option of the frame-relay interface-dlci command on the Cisco MC3810 is no longer supported beginning in this release.
Step 2	Router(config-if)# vofr cisco	Configure the Frame Relay DLCI to support VoFR and the Cisco proprietary fragmentation implementation. When this command is entered, data CID 4 and call-control CID 5 are automatically assigned. If you are configuring user-dialed calls, this procedure is complete. If you are configuring auto-ringdown calls, proceed to the next step.
Step 3	For Cisco 2600 and 3600 series analog voice ports: Router(config)# voice-port slot/subunit/port For Cisco 2600 and 3600 series digital voice ports: Router(config)# voice-port slot/port:ds0-group For Cisco MC3810 series analog voice ports: Router(config)# voice-port slot/port For Cisco MC3810 series digital voice ports: Router(config)# voice-port slot:ds0-group	Identify the voice port you want to configure and enter voice-port configuration mode.
Step 4	Router(config-voiceport)# connection plar destination-string	(Optional) For auto-ringdown calls, configure the PLAR connection, specifying the telephone number in the destination-string.

This configuration uses Cisco proprietary data fragmentation.

Configuring Cisco-Trunk Permanent (Private Line) Calls

This section describes how to configure Cisco-trunk permanent (private line) calls on the different router platforms. This section is divided into the following procedures:

• Configuring Voice over Frame Relay Dial Peers for Cisco-Trunk (Private Line) Calls

• Configuring Cisco Trunk Permanent Calls

• Configuring Cisco Trunk Permanent Calls to a Cisco MC3810 Running Cisco IOS Releases Before 12.1(2)T

Configuring Voice over Frame Relay Dial Peers for Cisco-Trunk (Private Line) Calls

If you are sending Cisco-trunk (private line) calls over the Frame Relay network, you must configure the Voice over Frame Relay dial peers to specifically support Cisco-trunk (private line) calls. Cisco-trunk (private line) calls are permanent calls.

One key task when you configure Cisco-trunk (private line) connections is to configure the signal type for the dial peer. The signal-type dial-peer command supports the following options:

• cas---Use the cas option to support North American CAS/robbed-bit signaling. This is the default signaling type.

• cept---Use the cept option to provide a basic E1 ABCD protocol, primarily for CEPT E&M signaling. This option is primarily used for European voice networks. If this option is used with FXS or FXO voice ports, the signaling used is equivalent to MEL CAS.

• ext-signal---Use the ext-signal option in cases where some external signaling channel is being used (for example, common channel signaling), or where no signaling information is being sent at all over a permanent "dumb" voice pipe. Applications where no signaling is required include using a simple voice pipe to carry audio for a public address system.

• transparent---Use the transparent option when the ABCD signaling bits are copied through from the T1/E1 interface "transparently" without modification or interpretation (also known as transparent FRF.11 signaling). This allows the router to handle or transport unknown signaling protocols. On a router with analog voice ports, the transparent option does not apply. If the transparent option is sent over analog voice ports, the signaling is equivalent to the cept option.

Configure the signal type so that the signal type that is selected in the dial peers on the routers at both ends of the permanent voice call are the same. When you configure a permanent connection between a T1/E1 Cisco MC3810 and an analog voice port on a Cisco 2600 or Cisco 3600 series routers, set the signal type to cas, which is the default.

Cisco 2600 and Cisco 3600 analog voice ports do not support the cept or transparent signal types. The T1/E1 Cisco MC3810 can also be set to transparent, which simply passes the signaling through from the Cisco 2600 or Cisco 3600 series routers without interpretation. However, when transparent is used, the Cisco MC3810 makes no assumptions regarding the on-hook and off-hook state of the call. By default, when configured by using transparent, the Cisco MC3810 operates the voice path in the permanently open state, so that voice packets are sent (and network bandwidth consumed) regardless of the state of the call.

To configure a VoFR dial peer to support Cisco-trunk permanent (private line) calls, use the following commands beginning in global configuration mode:

	Command	Purpose
Step 1	Router(config)# dial-peer voice number vofr	Define a VoFR dial peer and enter dial-peer configuration mode. All subsequent commands that you enter in dial-peer voice mode before you exit will apply to this dial peer. The number tag value identifies the dial peer and must be unique on the router. Do not duplicate a specific tag number.
Step 2	Router(config-dial-peer)# destination-pattern string	Configure the dial peer's destination pattern. The same restrictions for the string listed in the POTS dial-peer configuration also apply to the VoFR destination pattern.
Step 3	Router(config-dial-peer)# session target interface dlci [cid]	Configure the Frame Relay session target for the dial peer.
Step 4	Router(config-dial-peer)# session protocol cisco-switched	Configure the session protocol to support switched calls. This is the default setting, and entering this command is not required.
Step 5	Router(config-dial-peer)# codec type [bytes bytes]	Specify the voice coder rate of speech and payload size for the dial peer. The default dial peer codec is g729r8. Note that the Cisco MC3810 is limited to a maximum of 12 calls when using g729r8; to support up to 24 calls on the Cisco MC3810, use g729ar8. Specifying the payload size by entering the bytes value is optional. Each codec type defaults to a different payload size if you do not specify a value. To obtain a list of the default payload sizes, enter the codec command and the bytes option followed by a question mark (?). Note On the Cisco MC3810, you can also assign codec values to the voice port. When you configure the codec type for regular switched voice calls, you must set the codec type on the Cisco MC3810 voice port. When you configure the codec for permanent calls (cisco-trunk and frf11-trunk), you must configure the codec type on the dial peer. You cannot specify the payload size on the voice port.
Step 6	Router(config-dial-peer)# dtmf-relay	(Optional) If the codec type is a low bit-rate codec such as g729 or g723, specify support for DTMF relay to improve end-to-end transport of DTMF tones. DTMF tones do not always propagate reliably with low bit-rate codecs. DTMF relay is disabled by default.
Step 7	Router(config-dial-peer)# signal-type {cas | cept | ext-signal | transparent}	Define the flavor of the ABCD signaling packets that are generated by the voice port and sent to the data network. Enter cas to support CAS. Enter cept to support the European CEPT standard (related to MEL CAS). Enter ext-signal to indicate that ABCD signaling packets should not be sent, for configurations where the line signaling information is carried externally to the voice port. Enter transparent (for digital T1/E1 interfaces) to read the ABCD signaling bits directly from the T1/E1 interface without interpretation, and to pass them transparently to the data network (this is also known as transparent FRF.11 signaling).
Step 8	Router(config-dial-peer)# no vad	(Optional) Disable voice activity detection (VAD) on the dial peer. This command is enabled by default.
Step 9	Router(config-dial-peer)# sequence-numbers	(Optional) Enable the voice sequence number if required for your configuration. This command is disabled by default.
Step 10	Router(config-dial-peer)# preference value	(Optional) Configure a preference for the VoFR dial peer. The value is a number from 0 through 10 where the lower the number, the higher the preference in hunt groups.
Step 11	Router(config-dial-peer)# fax rate {2400 | 4800 | 7200 | 9600 | 14400 | disable | voice}	(Optional) Configure the transmission speed (in bps) at which a fax will be sent to the dial peer. The default is voice, which specifies the highest possible transmission speed allowed by the voice rate.
Step 12		To configure another VoFR dial peer, exit dial-peer configuration mode and repeat steps 1 through 11.

Configuring Cisco Trunk Permanent Calls

You can configure Cisco trunk permanent calls on Cisco 2600, 3600, and 7200 series routers, and on Cisco MC3810 concentrators.

Note If you are configuring Cisco trunk permanent calls to Cisco MC3810 concentrators running Cisco IOS releases before 12.1(2)T, see "Configuring Cisco Trunk Permanent Calls to a Cisco MC3810 Running Cisco IOS Releases Before 12.1(2)T" section.

To configure Cisco trunk permanent calls on these routers, use the following commands from interface configuration mode:

	Command	Purpose
Step 1	Router(config-if)# frame-relay interface-dlci dlci	Configure the Frame Relay DLCI and enter DLCI configuration mode. Note The voice-encap option of the frame-relay interface-dlci command on the Cisco MC3810 is no longer supported beginning in this release.
Step 2	Router(config-if)# vofr [data cid] [call-control [cid]]	Configure the Frame Relay DLCI to support VoFR. Note When you enter the vofr command, all subchannels on the DLCI are configured for FRF.11 encapsulation. If you enter the vofr command without any keywords or arguments, the data subchannel is CID 4 and there are no call-control subchannel. If you are configuring tandem calls, this step ends your configuration.
Step 3	For Cisco 2600 and 3600 series analog voice ports: Router(config)# voice-port slot/subunit/port For Cisco 2600 and 3600 series digital voice ports: Router(config)# voice-port slot/port:ds0-group For Cisco MC3810 series analog voice ports: Router(config)# voice-port slot/port For Cisco MC3810 series digital voice ports: Router(config)# voice-port slot:ds0-group	Identify the voice port you want to configure and enter voice-port configuration mode.
Step 4	Router(config-voiceport)# connection trunk destination-string [answer-mode]	For private line calls, configure the trunk connection by specifying the telephone number in the destination-string. When configuring Cisco trunk permanent calls, one side must be the call initiator (master) and the other side is normally the call answerer (slave). By default, the voice operates in master mode. Enter the answer-mode keyword to specify that the voice port operates in slave mode.
Step 5	Router(config-voiceport)# shutdown	Shut down the voice port.
Step 6	Router(config-voiceport)# no shutdown	Reactivate the voice port to enable the trunk connection to take effect.

This configuration uses standard FRF.11 Annex C fragmentation.

Note Every time you enter the connection trunk or no connection trunk command, you must toggle the voice port (by entering shutdown, then no shutdown) for the changes to take effect.

Configuring Cisco Trunk Permanent Calls to a Cisco MC3810 Running Cisco IOS Releases Before 12.1(2)T

To configure Cisco trunk permanent calls to a Cisco MC3810 running Cisco IOS releases before 12.1(2)T, use the following commands from interface configuration mode:

	Command	Purpose
Step 1	Router(config-if)# frame-relay interface-dlci dlci	Configure the Frame Relay DLCI and enter DLCI configuration mode.
Step 2	Router(config-if)# vofr cisco	Configure the Frame Relay DLCI to support VoFR and the Cisco proprietary data implementation. When this command is entered, data CID 4 and call-control CID 5 are automatically assigned.
Step 3	For Cisco 2600 and 3600 series analog voice ports: Router(config)# voice-port slot/subunit/port For Cisco 2600 and 3600 series digital voice ports: Router(config)# voice-port slot/port:ds0-group For Cisco MC3810 series analog voice ports: Router(config)# voice-port slot/port For Cisco MC3810 series digital voice ports: Router(config)# voice-port slot:ds0-group	Identify the voice port you want to configure and enter voice-port configuration mode.
Step 4	Router(config-voiceport)# connection trunk destination-string [answer-mode]	For private line calls, configure the trunk connection, specifying the telephone number in destination-string. When configuring Cisco trunk permanent calls, one side must be the call initiator (master) and the other side is normally the call answerer (slave). By default, the voice operates in master mode. Enter the answer-mode keyword to specify that the voice port should operate in slave mode.
Step 5	Router(config-voiceport)# shutdown	Shut down the voice port.
Step 6	Router(config-voiceport)# no shutdown	Reactivate the voice port to enable the trunk connection to take effect.

This configuration uses Cisco proprietary data fragmentation.

Note Every time you enter the connection trunk or no connection trunk command, you must toggle the voice port (by entering shutdown, then no shutdown) for the changes to take effect.

Configuring FRF.11 Trunk (Private Line) Calls

On the Cisco MC3810 and on Cisco 2600 and 3600 series routers, you can configure FRF.11 trunk calls to a second router.

You cannot configure FRF.11 trunk calls for tandem VoFR configurations.

Note This configuration requires that you set the session protocol dial-peer configuration command to frf11-trunk.

To configure FRF.11 trunk (private line) calls, use the following commands from interface configuration mode:

	Command	Purpose
Step 1	Router(config-if)# frame-relay interface-dlci dlci	Configure the Frame Relay DLCI and enter DLCI configuration mode.
Step 2	Choose one of the following:
a.	Router(config-if)# vofr [data cid] [call-control cid]	(Cisco 2600 and Cisco 3600 series routers) Configure the Frame Relay DLCI to support VoFR and to optionally enter the data and call-control CIDs.
b.	Router(config-if)# vofr [data cid]	(Cisco MC3810) Configure the Frame Relay DLCI to support VoFR and to optionally enter the data CID. The call-control option is not supported on the Cisco MC3810. Note When you enter the vofr command is used, all subchannels on the DLCI are configured for FRF.11 encapsulation except the data subchannel. If you enter the vofr command without any keywords or arguments, the data subchannel is CID 4 and there is no call-control subchannel.
Step 3	For Cisco 2600 and 3600 series analog voice ports: Router(config)# voice-port slot/subunit/port For Cisco 2600 and 3600 series digital voice ports: Router(config)# voice-port slot/port:ds0-group For Cisco MC3810 series analog voice ports: Router(config)# voice-port slot/port For Cisco MC3810 series digital voice ports: Router(config)# voice-port slot:ds0-group	Identify the voice port you want to configure and enter voice-port configuration mode.
Step 4	Router(config-voiceport)# connection trunk destination-string [answer-mode]	For private line calls, configure the trunk connection by specifying the telephone number in the destination-string. When configuring FRF.11 trunk calls, one side must be the call initiator (master) and the other side is normally the call answerer (slave). By default, the voice port is the master. Enter the answer-mode keyword to specify that the voice port is the slave.

This configuration uses FRF.11 Annex C data fragmentation.

Note Every time you enter the connection trunk or no connection trunk command, you must toggle the voice port (by entering shutdown, then no shutdown) for the changes to take effect.

Configuring Connections for Tandem Nodes

Tandeming is switching incoming VoFR calls on a Frame Relay DLCI to an outgoing VoFR enabled DLCI. Tandeming works for switched calls and Cisco-trunk permanent calls only. You cannot tandem FRF.11 trunk calls over a multihop network.

Tandeming is supported on the Cisco MC3810 and on Cisco 2600, 3600, and 7200 series routers.

Note When creating voice networks with a mixture of router types, the Cisco MC3810 must be running Cisco IOS Release 12.0(3)XG, 12.0(4)T, or later releases to act as a tandem node.

Depending on which router is used as the end node and which router is used as the tandem node, you must use the correct Frame Relay PVC type when configuring your connections. Table 1 shows the different combinations of routers that can serve as end nodes and tandem nodes, and the Frame Relay PVC type required.

Table 2: VoFR End Node and Tandem Node Combinations That Are Supported

End Node(s)	Tandem Node	vofr Command to Enter for the Frame Relay DLCI
Cisco 2600 or Cisco 3600, Cisco MC3810 or Cisco 7200	Cisco 2600, Cisco 3600, Cisco MC3810 or Cisco 7200	vofr call-control
Cisco 2600 or Cisco 3600, Cisco MC3810	Cisco MC3810 running Cisco IOS releases before 12.1(2)T	vofr cisco
Cisco MC3810 running Cisco IOS releases before 12.1(2)T	Cisco 2600, Cisco 3600, or Cisco 7200	vofr cisco

Verifying Your Voice Connections

Verify that the voice connection for switched calls is working by following these steps:

Step 2 Make a call from the local telephone to a configured dial peer and verify that the call attempt is successful.

Verify that the voice connection for FXO-FXS trunk calls from a telephone to a remote PBX is working by doing the following:

Step 2 Dial digits so that the remote PBX routes the call.

You can check the validity of your dial-peer and voice-port configuration by performing the following tasks:

• If you have relatively few dial peers configured, enter the show dial-peer voice command to verify that the data configured is correct. On the Cisco MC3810, enter the show dial-peer voice summary command.

• To show the status of the voice ports, enter the show voice port command.

• To show the call status for all voice ports, enter the show call active voice [brief]. On the Cisco MC3810, use the show voice call command.

• To show the current status of all DSP voice channels on the Cisco MC3810, enter the show voice dsp command.

You can check the validity of your VoFR configuration on the DLCI by performing the following task:

• To show the VoFR configuration, enter the show frame-relay vofr [interface [dlci [cid]]] command. This command is not supported on the Cisco MC3810 when the vofr cisco command is configured.

• To show the status of Cisco-trunk permanent calls (private-line) on the Cisco MC3810, enter the show voice permanent command.

Troubleshooting Tips

If you are having trouble connecting a call, you can try to resolve the problem by performing the following tasks:

• If no calls are going through, make sure that the frame-relay voice bandwidth command is configured.

• If you have Voice over Frame Relay configured on a PVC and are experiencing problems with data connectivity on that PVC, make sure that the frame-relay fragment command has been configured.

• If data is not being transmitted but fragmentation is configured, make sure that Frame Relay traffic shaping is turned on.

• If you suspect that the problem is with the dial plan or the dial peers, use the show dial-plan number dial string command to display which dial peers are used when a specific number is called.

• If you have problems connecting an FRF.11 trunk call, make sure that the session protocol dial-peer command is set to frf11-trunk.

• If you are configuring FRF.11 trunk calls on the Cisco 2600 or Cisco 3600, verify that the called-number vofr dial-peer command is configured and that its number matches the destination pattern of the corresponding POTS dial peer.

• Be sure that the voice port is set to no shutdown.

• Be sure that the serial port or the T1/E1 controller is set to no shutdown.

• Be sure to toggle the voice port (by first entering shutdown, then no shutdown) every time you enter the connection trunk or no connection trunk commands.

Configuration Examples

This section provides specific configuration examples for different VoFR connections and call type scenarios. This section includes the following examples:

• Two Routers Using Frame Relay Fragmentation

• Two Routers Using a VoFR PVC

• Router Using a VoFR PVC to a Cisco MC3810 Running Cisco IOS Releases Before 12.1(2)T

• Cisco-Trunk (Private Line) Calls Between Two Routers

• FRF.11 Trunk Calls Between Two Routers

• Tandem Configuration with Three Routers for Switched Calls

• Tandem Configuration with a Cisco MC3810 Tandem Node for Switched Calls

• Tandem Configuration with a Cisco MC3810 Endpoint Node for Cisco-Trunk (Private Line) Calls

• Tandem Configuration with All Cisco MC3810 Concentrators for Switched Calls

• Cisco Trunk Call with Hunt Groups

Note In the examples, some commands are shown with a lowercase letter in boldface. These letters indicate command settings that must match on the different routers. For example, the frame-relay cir s value indicates that the committed information rate "s" must match on the routers as shown.

The examples do not provide complete configurations, but show the required commands to configure Voice over Frame Relay.

Two Routers Using Frame Relay Fragmentation

Figure 1 shows an example of Frame Relay fragmentation between two routers.

Two Routers Using a VoFR PVC

Figure 2 shows an example of two routers with connections using a VoFR PVC.

Router Using a VoFR PVC to a Cisco MC3810 Running Cisco IOS Releases Before 12.1(2)T

Figure 3 shows an example of a Cisco 3600 series router with connections to a Cisco MC3810 running a Cisco IOS Releases before12.1(2)T. In this example, the Voice over Frame Relay interface on both the Cisco 3600 and the Cisco MC3810 is configured by using the vofr cisco command.

Cisco-Trunk (Private Line) Calls Between Two Routers

Figure 4 shows an example of VoFR Cisco-trunk (private line) calls between two routers.

FRF.11 Trunk Calls Between Two Routers

Figure 5 shows an example of FRF.11 trunk calls configured between two routers.

Tandem Configuration with Three Routers for Switched Calls

Figure 6 shows an example of a tandem configuration with two Cisco 3600 routers as endpoints and a third Cisco 3600 as a tandem node.

Tandem Configuration with a Cisco MC3810 Tandem Node for Switched Calls

Figure 7 shows an example of a tandem configuration with a Cisco MC3810 acting as a tandem node.

Tandem Configuration with a Cisco MC3810 Endpoint Node for Cisco-Trunk (Private Line) Calls

Figure 8 shows an example of a tandem configuration with a Cisco MC3810 acting as an endpoint node for Cisco-trunk (private line) calls.

Tandem Configuration with All Cisco MC3810 Concentrators for Switched Calls

Figure 9 shows an example of a tandem configuration with Cisco MC3810 concentrators as both endpoint and tandem nodes.

Note When a Cisco MC3810 running Cisco IOS releases before 12.1(2)T is on a VoFR network, the configuration for connections to and from that Cisco MC3810 is slightly different than for other routers that support VoFR. The vofr cisco command is required for these connections on the Cisco MC3810.

Cisco Trunk Call with Hunt Groups

Figure 10 shows an example of a Cisco trunk (private line) call that is configured with hunt groups. In this example, the two routers are in master-slave mode with a backup path. Router B is configured as a slave and Router A is configured as the master. The master makes periodic attempts to establish the trunk until the trunk is established. Two dial peers match the destination string configured in the voice port, but because one dial peer has a higher preference than the other dial peer, the call setup is attempted through that dial peer. If the call setup fails, the master can continue attempting call setups by using the next available dial peer. After all dial peers are exhausted, the master can continue following the list cyclically by starting again from the dial peer with the highest preference.

Command Reference

This section documents new or modified commands. All other commands used with this feature are documented in the Cisco IOS Release 12.1 command reference publications.

See new and modified debug commands in the "Debug Commands" section.

The following new and modified commands are described in this section (modified commands are marked by an asterisk):

• dial-peer hunt

• dial-peer terminator*

• dial-peer voice*

• forward-digits

• frag-pre-queuing*

• frame-relay interface-dlci*

• huntstop*

• signal-type*

• vofr*

• voice hunt user-busy

dial-peer hunt

To specify a hunt selection order for dial-peers, use the dial-peer hunt dial-peer configuration command. Use the no form of this command to restore the default selection order.

Router# configure terminal
Router(config)# dial-peer hunt 0

dial-peer terminator

To change the character used as a terminator for variable-length dialed numbers, use the dial-peer terminator global configuration command. Use the no form of this command to restore the default terminating character.

Syntax Description

character

Designates the terminating character for a variable-length dialed number. Valid numbers and characters are #, *, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, a, b, c, and d. The default is #.

Defaults

The default terminating character is #.

Command Modes

Global configuration

Command History

Release	Modification
12.0	This command was introduced.
12.0(7)XK	Usage was restricted to variable-length dialed numbers.
12.1(2)T	This command was implemented in Cisco IOS Release 12.1(2)T.

Usage Guidelines

There are certain areas in the world, for example, in certain European countries, where telephone numbers can vary in length. When a dialed-number string is identified as a variable length dialed-number, the system does not place a call until the configured value for the timeouts interdigits command has expired, or until the caller dials the terminating character. Use the dial-peer terminator global configuration command to change the terminating character.

Examples

The following example specifies "9" as the terminating character for variable-length dialed numbers:

Router# configure terminal
Router(config)# dial-peer terminator 9#

Related Commands

Command	Description
answer-address	Specifies the preferred selection order of a dial peer within a hunt group.
destination-pattern	Specifies the prefix or the complete telephone number for a dial peer.
timeouts interdigit	Specifies the interdigit timeout value for a voice port in seconds.
show dial-peer voice	Displays configuration information for dial peers.

dial-peer voice

To enter dial-peer configuration mode and specify the method of voice encapsulation, use the dial-peer voice global configuration command.

For the Cisco 2600 series routers

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

no dial-peer voice tag

For the Cisco 3600 series routers and the Cisco MC3810 concentrator

dial-peer voice tag {pots | voip | vofr | voatm}

no dial-peer voice tag

Syntax Description

tag	A number identifying a particular dial peer. Valid entries are 1 through 2147483647.
pots	POTS dial peer using basic telephone service.
voip	VoIP dial peer using voice encapsulation on the POTS network.
vofr	Voice over Frame Relay dial peer using encapsulation on the Frame Relay backbone network.
voatm	(Cisco 3600 series routers and MC3810 concentrators only) Voice over ATM dial peer using real-time AAL5 voice encapsulation on the ATM backbone network.

Defaults

No default behavior or values.

Command Modes

Global configuration

Command History

Release	Modification
11.3(1)T	This command was introduced.
11.3(1)MA	This command was first supported on the Cisco MC3810 with support for POTS, VoFR and VoATM.
12.0(3)XG	This command added VoFR to the Cisco 2600 and 3600 series routers.
12.0(4)T	This command added VoFR to the Cisco 7200 series platform.
12.0(7)XK	This command added VoIP to the Cisco MC3810 and VoATM to the Cisco 3600 series router. Support for VoHDLC on the Cisco MC3810 was removed in this release.
12.1(2)T	This command was implemented in Cisco IOS Release 12.1(2)T.

Use the dial-peer voice global configuration command to switch to the dial-peer configuration mode from the global configuration mode. Use the exit command to exit the dial-peer configuration mode and return to the global configuration mode.

Examples

The following example accesses dial-peer configuration mode and configures a POTS peer identified as dial peer 10:

Router# configure terminal
Router(config)# dial-peer voice 10 pots

Related Commands

Command	Description
voice-port	Enters voice-port configuration mode.

forward-digits

To specify which digits to forward for voice calls, use the forward-digits dial-peer configuration command. If the no form of this command is entered, any digits not matching the destination-pattern are not forwarded. Use the default form of this command to restore the default state.

Syntax Description

num-digit	The number of digits to be forwarded. If the number of digits is greater than the length of a destination phone number, the length of the destination number is used. The valid range is 0 to 32. Setting the value to 0 is equivalent to entering no forward-digits.
all	Forward all digits. If all is entered, the full length of the destination pattern is used.
extra	If the length of the dialed digit string is greater than the length of the dial-peer destination pattern, the extra right-justified digits are forwarded. However, if the dial-peer destination pattern is variable length (ending with character "T", for example: T, 123T, 123...T), extra digits are not forwarded.

Defaults

Dialed digits not matching the destination pattern are forwarded.

Command Modes

Dial-peer configuration

Command History

Release	Modification
11.3(1) MA	This command was introduced on the Cisco MC3810.
12.0(2)T	The implicit option was added.
12.0(4)T	This command was modified to support ISDN PRI QSIG signaling calls.
12.0(7)XK	This command was first supported on the Cisco 2600 and 3600 series routers, the implicit keyword was removed, and the extra keyword was added.
12.1(2)T	This command was implemented in Cisco IOS Release 12.1(2)T.

Usage Guidelines

This command applies only to POTS dial peers.

Forwarded digits are always right-justified, so that extra leading digits are stripped.

The destination pattern includes both explicit digits and wildcards if present.

Use the default form of this command if a non-default digit-forwarding scheme was entered previously and you wish to restore the default.

For QSIG ISDN connections, entering forward-digits all implies that all the digits of the called party number are sent to the ISDN connection. When you enter forward-digits num-digit and enter a number from 1 to 32, the number of digits specified (right justified) of the called part number are sent to the ISDN connection.

Examples

The following example forwards all of the digits in the destination pattern of a POTS dial peer:

Router(config)# dial-peer voice 1 pots
Router(config-dial-peer)# destination-pattern 8...
Router(config-dial-peer)# forward-digits all
 

The following example forwards four of the digits in the destination pattern of a POTS dial peer:

Router(config)# dial-peer voice 1 pots
Router(config-dial-peer)# destination-pattern 555....
Router(config-dial-peer)# forward-digits 4
 

The following example forwards the extra right-justified digits that exceed the length of the destination pattern of a POTS dial peer:

Router(config)# dial-peer voice 1 pots
Router(config-dial-peer)# destination-pattern 555....
Router(config-dial-peer)# forward-digits extra

Related Commands

Command	Description
destination-pattern	Defines the prefix or the full E.164 telephone number to be used for a dial peer.
show dial-peer voice	Displays configuration information for dial peers.

frag-pre-queuing

This command was added in Cisco IOS Release 12.0(2)T on the Cisco MC3810. Beginning with Cisco IOS Release 12.1(2)T, this command is no longer supported.

frame-relay interface-dlci

To assign a data link connection identifier (DLCI) to a specified Frame Relay subinterface on the router or access server, use the frame-relay interface-dlci interface configuration command. Use the no form of this command to remove this assignment.

Command History

Release	Modification
10.0	This command was introduced.
11.3(1)MA	The voice-encap option was added for the Cisco MC3810.
12.0(2)T	The voice-cir option was added for the Cisco MC3810.
12.0(3)XG	Additional usage guidelines added.
12.0(4)T	This command was implemented in Cisco IOS Release 12.0(4)T.
12.0(7)XK	The voice-encap option on the Cisco MC3810 was removed. This option is no longer supported.
12.1(2)T	This command was implemented in Cisco IOS Release 12.1(2)T.

Examples

The following example shows how to configure Frame Relay DLCI and enter DLCI configuration mode:

Router(config-if)# frame-relay interface-dlci dlci

huntstop

To disable all further dial-peer hunting if a call fails when using hunt groups, enter the huntstop dial-peer configuration command. To reenable dial-peer call hunting, enter the no form of this command.

Syntax Description

This command has no arguments or keywords.

Defaults

Disabled

Command Modes

Dial-peer configuration

Command History

Release	Modification
12.0(5)T	This command was introduced on the Cisco MC3810.
12.0(7)XK	Support for this command was extended to the Cisco 2600 and 3600 series routers.
12.1(2)T	This command was implemented in Cisco IOS Release 12.1(2)T.

Usage Guidelines

Once you enter this command, no further hunting is allowed if a call fails on the specified dial peer.

This command can be used with all types of dial peers.

Examples

The following example shows how to disable dial-peer hunting on a specific dial peer:

Router(config)# dial peer voice 100 vofr
Router(config-dial-peer)# huntstop
 

The following example shows how to reenable dial-peer hunting on a specific dial peer:

Router(config)# dial peer voice 100 vofr
Router(config-dial-peer)# no huntstop

Related Commands

Command	Description
dial-peer voice	Enters dial-peer configuration mode and specifies the method of voice-related encapsulation.

signal-type

To set the signaling type to be used when connecting to a dial peer, use the signal-type command from dial-peer configuration mode. To return to the default signal-type, use the no form of this command.

Syntax Description

cas	North American EIA-464 Channel-Associated Signaling (robbed bit signaling). If the Digital T1 Packet Voice Trunk Network Module is installed, this option might not be available.
cept	Provides a basic E1 ABCD signaling protocol. Used primarily for E&M interfaces. When used with FXS/FXO interfaces, this protocol is equivalent to MELCAS.
ext-signal	External signaling. The DSP does not generate any signaling frames. Use this option when there is an external signaling channel, for example, CCS, or when you need to have a permanent "dumb" voice pipe.
transparent	On the Cisco MC3810, selecting this option produces different results depending on whether you are using a digital voice module (DVM) or an analog voice module (AVM). For a DVM: The ABCD signaling bits are copied from or transported through the T1/E1 interface "transparently" without modification or interpretation. This enables the MC3810 to handle arbitrary or unknown signaling protocols. For an AVM: It is not possible to provide "transparent" behavior because the Cisco MC3810 must interpret the signaling information in order to read and write the correct state to the analog hardware. This option is mapped to be equal to cas.

Defaults

cas

Command Modes

Dial-peer configuration

Command History

Release	Modification
12.0(3)XG	This command was introduced.
12.0(4)T	Support was added for the Cisco 7200 series router.
12.0(7)XK	In previous releases, the cept and transparent options were supported only on the Cisco MC3810. Beginning in this release, these options are supported on the Cisco 2600, Cisco 3600 and Cisco 7200 series routers.
12.1(2)T	This command was implemented in Cisco IOS Release 12.1(2)T.

Usage Guidelines

This command applies to VoFR and VoATM dial peers. It is used with permanent connections only (Cisco trunks and FRF.11 trunks), not with switched calls.

This command is used to inform the local telephony interface of the type of signaling it should expect to receive from the far-end dial peer. To turn signaling off at this dial peer, select the ext-signal option. If signaling is turned off and there are no external signaling channels, a "hot" line exists, enabling this dial peer to connect to anything at the far end.

When you connect an FXS to another FXS, or if you have anything other than an FXS/FXO or E&M/E&M pair, the appropriate signaling type on Cisco 2600 series and 3600 series routers is ext-signal (disabled).

If you have a digital E1 connection at the remote end that is running cept/MELCAS signaling and you then trunk that across to an analog port, you should make sure that you configure both ends for the cept signal-type.

If you have a T1 or E1 connection at both ends and the T1/E1 is running a signaling protocol that is neither EIA-464 or cept/MELCAS, you might want to configure the signal-type for the transparent option in order to pass through the signaling.

Examples

The following example shows how to disable signaling on a Cisco 2600 series or 3600 series router or on a Cisco MC3810 concentrator for VoFR dial peer 200, starting from global configuration mode:

Router(config)# dial-peer voice 200 vofr
Router(config-dial-peer)# signal-type ext-signal
Router(config-dial-peer)# 

Related Commands

Command	Description
codec (dial-peer)	Specifies the voice coder rate of speech for a dial peer.
connection	Specifies the connection mode for a voice port.
destination-pattern	Specifies the telephone number associated with a dial peer.
dtmf-relay	Enables the DSP to generate FRF.11 Annex A frames for a dial peer.
preference	Enables the preferred dial peer to be selected when multiple dial peers within a hunt group are matched for a dial string.
session protocol	Establishes the VoFR protocol for calls between local and remote routers.
session target	Specifies a network-specific address for a dial peer.
sequence-numbers	Enables the generation of sequence numbers in each frame generated by the DSP.

vofr

To enable Voice over Frame Relay (VoFR) on a specific DLCI and to configure specific subchannels on that DLCI, use the vofr command from Frame Relay DLCI configuration mode. Use the no form of the command to disable VoFR on a specific DLCI.

For switched calls

vofr [data cid] [call-control [cid]]

no vofr [data cid] [call-control [cid]]

For switched calls to Cisco MC3810 concentrators running Cisco IOS releases before 12.0(7)XK and 12.1(2)T

vofr [cisco]

no vofr [cisco]

For Cisco-trunk permanent calls

vofr data cid call-control cid

no vofr data cid call-control cid

For Cisco-trunk permanent calls to Cisco MC3810 concentrators running Cisco IOS releases before 12.0(7)XK and 12.1(2)T

vofr cisco

no vofr cisco

For FRF-11 trunk calls

vofr [data cid] [call-control cid]

no vofr [data cid] [call-control cid]

Syntax Description

data	(Required for Cisco-trunk permanent calls. Optional for switched calls.) Used to select a subchannel (CID) for data other than the default subchannel, which is 4.
cid	(Optional) Specifies the subchannel to be used for data. Valid values are from 4 through 255; the default is 4. If data is specified, enter a valid CID.
call-control	(Optional) Used to specify that a subchannel will be reserved for call-control signaling. This option is not supported on the Cisco MC3810.
cisco	(Optional) Cisco proprietary voice encapsulation for VoFR with data is carried on CID 4 and call-control on CID 5. This option is required when configuring switched calls or Cisco trunks to Cisco MC3810 concentrators running Cisco IOS releases before 12.0(7)XK and 12.1(2)T. If you are configuring switched calls or Cisco trunks to Cisco MC3810 concentrators running Cisco IOS release 12.0(7)XK and 12.1(2)T and later releases, do not use this option.

Defaults

Disabled

Command Modes

Frame Relay DLCI

Command History

Release	Modification
12.0(3)XG	This command was introduced.
12.0(4)T	This command was implemented in 12.0(4)T.
12.0(7)XK	The use of the cisco option was modified. Beginning in this release, use the cisco option only when configuring connections to Cisco MC3810 concentrators running Cisco IOS releases before 12.0(7)XK and 12.1(2)T.
12.1(2)T	This command was implemented in Cisco IOS Release 12.1(2)T.

Usage Guidelines

Table 3 lists the different options of the vofr command and which combination of options is used beginning in Cisco IOS Release 12.0(7)XK and 12.1(2)T.

Table 3: Combinations of the vofr Command

Type of Call	vofr Command Combination to Use
Switched call (user dialed or auto-ringdown) to other routers supporting VoFR	vofr [data cid] [call-control [cid]]1
Switched call (user dialed or auto-ringdown) to a Cisco MC3810 running Cisco IOS releases before 12.0(7)XK and 12.1(2)T	vofr cisco2
Cisco-trunk permanent call (private-line) to other routers supporting VoFR	vofr data cid call-control cid
Cisco-trunk permanent call (private-line) to a Cisco MC3810 running Cisco IOS releases before 12.0(7)XK and 12.1(2)T	vofr cisco
FRF.11 trunk call (private-line) to other routers supporting VoFR	vofr [data cid] [call-control cid]3

1The recommended use of this command is vofr data 4 call-control 5. 2This command consumes data CID 4 and call-control CID 5. 3For FRF.111 trunk calls, the call-control option is not required. It is required only if you mix FRF.11 trunk calls with other types of voice calls on the same PVC.

Table 4 describes special conditions and restrictions for the use of the vofr command on the Cisco MC3810 running releases prior to 12.0(7)XK and 12.1(2)T.

Table 4: Using the vofr Command with the Cisco MC3810

Type of Call	Conditions and Restrictions
FRF.11 trunks	1. Do NOT use cisco option or call-control option. 2. Use vofr or vofr data cid.
Cisco trunks	1. Must use vofr cisco.
switched-vofr	1. Must use vofr cisco.

If you select the "data" option, enter a numeric value to complete the command. If you select the call-control option, you do not enter a numeric value if you wish to accept the default call-control subchannel. See the following examples for clarification.

When you use the vofr command on a Cisco MC3810 without the "cisco" option, switched calls are not permitted. You can only make permanent FRF.11-trunk calls.

---

Note It is not possible to configure the call-control option on a Cisco MC3810. If you configure this option, the setting is ignored.

---

Examples

The following example shows how to enable VoFR on Serial 1/1, DLCI 100 on a Cisco 2600 series, 3600 series, or 7200 series router or on a Cisco MC3810 concentrator, starting from global configuration mode:

Router(config)# interface serial 1/1
Router(config-if)# frame-relay interface-dlci 100
Router(config-fr-dlci)# vofr
Router(config-fr-dlci)# 
 

The above example configures CID 4 for data; no call-control CID is defined.

To configure CID 4 for data and CID 5 for call-control (both defaults), enter the following command:

Router(config-fr-dlci)# vofr call-control
Router(config-fr-dlci)# 
 

To configure CID10 for data and CID 15 for call-control, enter the following command:

Router(config-fr-dlci)# vofr data 10 call-control 15
Router(config-fr-dlci)# 
 

To configure CID 4 for data and CID 15 for call-control, enter the following command:

Router(config-fr-dlci)# vofr call-control 15
Router(config-fr-dlci)# 
 

To configure CID 10 for data and CID 5 for call-control, enter the following command:

Router(config-fr-dlci)# vofr data 10 call-control
Router(config-fr-dlci)# 
 

To configure CID 10 for data with no call-control, enter the following command:

Router(config-fr-dlci)# vofr data 10
Router(config-fr-dlci)# 
 

To configure a Cisco router or MC3810 for a VoFR application with an older release of the Cisco MC3810 (before Release 12.0(3)XG), enter the following command:

Router(config-fr-dlci)# vofr cisco
Router(config-fr-dlci)# 

Related Commands

Command	Description
frame-relay interface-dlci	Assigns a data link connection identifier (DLCI) to a specified Frame Relay subinterface.
class	Assigns a VC class to a PVC.

voice hunt user-busy

To configure an originating or tandem router so it continues dial-peer hunting if it receives a user-busy disconnect code from a destination router, use the voice hunt user-busy command in global configuration mode. To configure the router so it stops dial-peer hunting if it receives a user-busy disconnect code (the default option), use the no form of this command.

Router(config)# voice hunt user-busy

Debug Commands

This section provides information on new and modified VoFR debug commands for the Cisco 2600 series, the Cisco 3600 series, and the Cisco MC3810 multiservice access concentrator.

All other debug commands used with Voice over Frame Relay are documented in the Cisco IOS Debug Command Reference for Cisco IOS Release 12.1.

The following new and modified commands are described in this section:

• debug ccfrf11 session

• debug ccswvoice vofr-debug

• debug ccswvoice vofr-session

• debug vtsp vofr subframe

debug ccfrf11 session

To display the ccfrf11 function calls during call setup and teardown, use the debug ccfrf11 session command from privileged EXEC mode. Use the no form of this command to turn off the debug function.

Syntax Description

This command has no keywords or arguments.

Command History

Release	Modification
12.0(3)XG	This command was introduced on the Cisco 2600 and Cisco 3600 series routers.
12.0(4)T	This command was implemented in Cisco IOS Release 12.0(4)T.
12.0(7)XK	This command was first supported on the Cisco MC3810.
12.1(2)T	This command was implemented in Cisco IOS Release 12.1(2)T.

Usage Guidelines

Use this command to display debug information about the various FRF.11 VoFR service provider interface (SPI) functions. Note that this debug command does not display any information regarding the proprietary Cisco switched-VoFR SPI.

This debug is useful only when the session protocol is "frf11-trunk."

Examples

The following example shows sample output from the debug ccfr11 session command:

Router# debug ccfrf11 session
INCOMING CALL SETUP (port setup for answer-mode):
*Mar  6 18:04:07.693:ccfrf11_process_timers:scb (0x60EB6040) timer (0x60EB6098) expired
*Mar  6 18:04:07.693:Setting accept_incoming to TRUE
*Mar  6 18:04:11.213:ccfrf11_incoming_request:peer tag 800:callingNumber=+2602100,
        calledNumber=+3622110
*Mar  6 18:04:11.213:ccfrf11_initialize_ccb:preffered_codec set(-1)(0)
*Mar  6 18:04:11.213:ccfrf11_evhandle_incoming_call_setup_request:calling +2602100,
        called +3622110 Incoming Tag 800
*Mar  6 18:04:11.217:ccfrf11_caps_ind:PeerTag = 800
*Mar  6 18:04:11.217:     codec(preferred) = 4, fax_rate = 2, vad = 2
*Mar  6 18:04:11.217:     cid = 30, config_bitmask = 0, codec_bytes = 20, signal_type=2
*Mar  6 18:04:11.217:     required_bandwidth 8192
*Mar  6 18:04:11.217:ccfrf11_caps_ind:Bandwidth reservation of 8192 bytes succeeded.
*Mar  6 18:04:11.221:ccfrf11_evhandle_call_connect:Entered
 
CALL SETUP (MASTER):
5d22h:ccfrf11_call_setup_request:Entered
5d22h:ccfrf11_evhandle_call_setup_request:Entered
5d22h:ccfrf11_initialize_ccb:preffered_codec set(-1)(0)
5d22h:ccfrf11_evhandle_call_setup_request:preffered_codec set(9)(24)
5d22h:ccfrf11_call_setup_trunk:subchannel linking successful
5d22h:ccfrf11_caps_ind:PeerTag = 810
5d22h:     codec(preferred) = 512, fax_rate = 2, vad = 2
5d22h:     cid = 30, config_bitmask = 1, codec_bytes = 24, signal_type=2
5d22h:     required_bandwidth 6500
5d22h:ccfrf11_caps_ind:Bandwidth reservation of 6500 bytes succeeded.
 
CALL TEARDOWN:
*Mar  6 18:09:14.805:ccfrf11_call_disconnect:peer tag 0
*Mar  6 18:09:14.805:ccfrf11_evhandle_call_disconnect:Entered
*Mar  6 18:09:14.805:ccfrf11_call_cleanup:freeccb 1, call_disconnected 1
*Mar  6 18:09:14.805:ccfrf11_call_cleanup:Setting accept_incoming to FALSE and starting
        incoming timer
*Mar  6 18:09:14.809:timer 2:(0x60EB6098)starts - delay (70000)
*Mar  6 18:09:14.809:ccfrf11_call_cleanup:Alive timer stopped
*Mar  6 18:09:14.809:timer 1:(0x60F64104) stops
*Mar  6 18:09:14.809:ccfrf11_call_cleanup:Generating Call record
*Mar  6 18:09:14.809:cause=10 tcause=10    cause_text="normal call clearing."
*Mar  6 18:09:14.809:ccfrf11_call_cleanup:Releasing 8192 bytes of reserved bandwidth
*Mar  6 18:09:14.809:ccfrf11_call_cleanup:ccb 0x60F6404C, vdbPtr 0x610DB7A4
        freeccb_flag=1, call_disconnected_flag=1

Related Commands

Command	Description
debug ccswvoice vofr-debug	Displays the ccswvoice function calls during call setup and teardown.
debug ccswvoice vofr-session	Displays the ccswvoice function calls during call setup and teardown.
debug vtsp vofr subframe	Displays the first 10 bytes (including header) of selected VoFR subframes for the interface.

debug ccswvoice vofr-debug

To display the ccswvoice function calls during call setup and teardown, use the debug ccswvoice vofr-debug command from privileged EXEC mode. Use the no form of this command to turn off the debug function.

Syntax Description

This command has no arguments or keywords.

Command History

Release	Modification
12.0(3)XG	This command was introduced on the Cisco 2600 and Cisco 3600 series routers.
12.0(4)T	This command was implemented in Cisco IOS Release 12.0(4)T.
12.0(7)XK	This command was first supported on the Cisco MC3810.
12.1(2)T	This command was implemented in Cisco IOS Release 12.1(2)T.

Usage Guidelines

Use this command when troubleshooting a VoFR call that uses the "cisco-switched" session protocol. This command provides the same information as the debug ccswvoice vofr-session command, but includes additional debugging information relating to the calls.

Examples

The following example shows sample output from the debug ccswvoice vofr-debug command:

Router# debug ccswvoice vofr-debug
CALL TEARDOWN:
3640_vofr(config-voiceport)#
*Mar  1 03:02:08.719:ccswvofr_bridge_drop:dropping bridge calls src 17 dst 16 dlci 100
      cid 9 state ACTIVE
*Mar  1 03:02:08.727:ccswvofr:callID 17 dlci 100 cid 9 state ACTIVE event O/G REL
*Mar  1 03:02:08.735:ccswvofr:callID 17 dlci 100 cid 9 state RELEASE event I/C RELCOMP
*Mar  1 03:02:08.735:ccswvofr_store_call_history_entry:cause=22 tcause=22 
      cause_text=no circuit.
3640_vofr(config-voiceport)#
 
CALL SETUP (outgoing):
*Mar  1 03:03:22.651:ccswvofr:callID 23 dlci -1 cid -1 state NULL event O/G SETUP
*Mar  1 03:03:22.651:ccswvofr_out_callinit_setup:callID 23 using dlci 100 cid 10 
*Mar  1 03:03:22.659:ccswvofr:callID 23 dlci 100 cid 10 state O/G INIT event I/C PROC
*Mar  1 03:03:22.667:ccswvofr:callID 23 dlci 100 cid 10 state O/G PROC event I/C CONN
ccfrf11_caps_ind:codec(preferred) = 0

Related Commands

Command	Description
debug ccfrf11 session	Displays the ccfrf11 function calls during call setup and teardown.
debug ccswvoice vofr-session	Displays the ccswvoice function calls during call setup and teardown.
debug vtsp vofr subframe	Displays the first 10 bytes (including header) of selected VoFR subframes for the interface.

debug ccswvoice vofr-session

To display the ccswvoice function calls during call setup and teardown, use the debug ccswvoice vofr-session command from privileged EXEC mode. Use the no form of this command to turn off the debug function.

Syntax Description

This command has no arguments or keywords.

Command History

Release	Modification
12.0(3)XG	This command was introduced on the Cisco 2600 and Cisco 3600 series routers.
12.0(4)T	This command was implemented in Cisco IOS Release 12.0(4)T.
12.0(7)XK	This command was first supported on the Cisco MC3810.
12.1(2)T	This command was implemented in Cisco IOS Release 12.1(2)T.

Usage Guidelines

Use this command to show the state transitions of the cisco-switched-vofr state machine as a call is processed, and when attempting to troubleshoot a VoFR call that uses the "cisco-switched" session protocol.

Examples

The following example shows sample output from the debug ccswvoice vofr-session command:

Router# debug ccswvoice vofr-session
CALL TEARDOWN:
3640_vofr(config-voiceport)#
*Mar  1 02:58:13.203:ccswvofr:callID 14 dlci 100 cid 8 state ACTIVE event O/G REL
*Mar  1 02:58:13.215:ccswvofr:callID 14 dlci 100 cid 8 state RELEASE event I/C RELCOMP
3640_vofr(config-voiceport)#
 
CALL SETUP (outgoing):
*Mar  1 02:59:46.551:ccswvofr:callID 17 dlci -1 cid -1 state NULL event O/G SETUP
*Mar  1 02:59:46.559:ccswvofr:callID 17 dlci 100 cid 9 state O/G INIT event I/C PROC
*Mar  1 02:59:46.567:ccswvofr:callID 17 dlci 100 cid 9 state O/G PROC event I/C CONN
3640_vofr(config-voiceport)#

Related Commands

Command	Description
debug ccfrf11 session	Displays the ccfrf11 function calls during call setup and teardown.
debug ccswvoice vofr-debug	Displays the ccswvoice function calls during call setup and teardown.
debug vtsp vofr subframe	Displays the first 10 bytes (including header) of selected VoFR subframes for the interface.

debug vtsp vofr subframe

To display the first 10 bytes (including header) of selected VoFR subframes for the interface, use the debug vtsp vofr subframe command in privileged EXEC mode. Use the no form of this command to turn off the debug function.

debug vtsp vofr subframe payload [from-dsp] [to-dsp]

no debug vtsp vofr subframe

Syntax Description

payload	Number used to selectively display subframes of a specific payload. The payload types are: 0: Primary Payload - WARNING! This option may cause network instability. 1: Annex-A 2: Annex-B 3: Annex-D 4: All other payloads 5: All payloads - WARNING! This option may cause network instability.
from-dsp	(Optional) Displays only the subframes received from the DSP.
to-dsp	(Optional) Displays only the subframes going to the DSP.

Command History

Release	Modification
12.0(3)XG	This command was introduced on the Cisco 2600 and Cisco 3600 series routers.
12.0(7)XK	Support for this command was extended to the Cisco MC3810.
12.1(2)T	This command was implemented in Cisco IOS Release 12.1(2)T.

Usage Guidelines

Each debug output displays the first 10 bytes of the FRF.11 subframe, including header bytes. Use the from-dsp and to-dsp options to limit the debugs to a single direction. If not specified, debugs are displayed for subframes when they are received from the DSP and before they are sent to the DSP.

Use extreme caution in selecting payload options 0 and 5. These options may cause network instability.

Examples

The following example shows sample output from the debug vtsp vofr subframe command:

Router# debug vtsp vofr subframe 2
vtsp VoFR subframe debugging is enabled for payload 2 to and from DSP 3620_vofr#
*Mar  6 18:21:17.413:VoFR frame received from Network (24 bytes):9E 02 19 AA AA AA AA
      AA AA AA
*Mar  6 18:21:17.449:VoFR frame received from DSP (18 bytes):9E 02 19 AA AA AA AA AA AA
      AA
*Mar  6 18:21:23.969:VoFR frame received from Network (24 bytes):9E 02 19 AA AA AA AA
      AA AA AA
*Mar  6 18:21:24.005:VoFR frame received from DSP (18 bytes):9E 02 19 AA AA AA AA AA AA
      AA

Related Commands Related Commands

Command	Description
debug vtsp all	Enables debugging of all VTSP areas.

Glossary

ABCD signaling---4-bit telephony line signaling coding in which each letter of "ABCD" represents one of the 4 bits. This is often associated with CAS or robbed-bit signaling on a T1 or E1 telephony trunk.

CID---Channel ID. Designates the Frame Relay subchannel ID for Voice over Frame Relay.

CIR---Committed information rate. The average rate of information transfer a subscriber (for example, a network administrator) has stipulated for a Frame Relay PVC.

Cisco-trunk (private line) call---A Cisco-trunk (private line) call is established by the forced connection of a dynamic switched call. A Cisco-trunk call is established during configuration of the trunk and stays up for the duration of the configuration. It optionally provides a pass-through connection path to pass signaling information between the two telephony interfaces at either end of the connection.

Codec---Coder-decoder. (i) An integrated circuit device that typically uses pulse code modulation to transform analog signals into a digital bit stream and digital signals back into analog signals. (ii) In Voice over IP, Voice over Frame Relay, and Voice over ATM, a DSP software algorithm used to compress/decompress speech or audio signals.

DLCI---Data-link connection identifier.

Dial peer---An addressable call endpoint that contains configuration information including voice protocol, codec type, and telephone number associated with the call endpoint. There are four kinds of dial peers: POTS, VoIP, VoFR, and VoATM.

DS0---A 64-kbps B channel on an E1 or T1 WAN interface.

DTMF---Dual-tone multifrequency. Uses two simultaneous voice-band tones for dial (such as touch tone).

DTMF relay---Enables the generation of FRF.11 Annex A frames for a VoFR dial peer. The DSP generates Annex A frames instead of passing a DTMF tone through the network as a voice sample.

Dynamic switched call---A telephone call dynamically established across a packet data network based on a dialed telephone number. In the case of VoFR, a Cisco proprietary session protocol similar to Q.931 is used to achieve call switching and negotiation between calling endpoints. The proprietary session protocol runs over FRF.11-compliant subchannels.

E&M---Stands for recEive and transMit (or Ear and Mouth). E&M is a trunking arrangement generally used for two-way switch-to-switch or switch-to-network connections. Cisco's analog E&M interface is an RJ-48 connector that allows connections to PBX trunk lines (tie lines). E&M is also available on E1 and T1 digital interfaces.

FIFO---First-in, first-out. In data communication, FIFO refers to a buffering scheme where the first byte of data entering the buffer is the first byte retrieved by the CPU. In telephony, FIFO refers to a queuing scheme where the first calls received are the first calls processed.

FRF---Frame Relay Forum. An association of corporate members consisting of vendors, carriers, users, and consultants committed to the implementation of Frame Relay in accordance with national and international standards. Go to http://www.frforum.com.

FRF.11---Frame Relay Forum implementation agreement for Voice over Frame Relay (v1.0 May 1997). This specification defines multiplexed data, voice, fax, DTMF digit-relay and CAS/robbed-bit signaling frame formats, but does not include call setup, routing, or administration facilities. Go to http://www.frforum.com.

FRF.11 Annex C---See FRF.12.

FRF11-trunk---A point-to-point permanent voice connection (private line) conforming to the FRF.11 specification.

FRF.12---The FRF.12 Implementation Agreement (also known as FRF.11 Annex C) was developed to allow long data frames to be fragmented into smaller pieces and interleaved with real-time frames. In this way, real-time voice and non-real-time data frames can be carried together on lower-speed links without causing excessive delay to the real-time traffic. Go to http://www.frforum.com.

FXO---Foreign Exchange Office. An FXO interface connects to the Public Switched Telephone Network's (PSTN) central office and is the interface offered on a standard telephone. Cisco's FXO interface is an RJ-11 connector that allows an analog connection to be directed at the PSTN's central office or to a station interface on a PBX.

FXS---Foreign Exchange Station. An FXS interface connects directly to a standard telephone and supplies ring, voltage, and dial tone. Cisco's FXS interface is an RJ-11 connector that allows connections to basic telephone service equipment, keysets, and PBXs.

hookflash---A short on-hook period usually generated by a telephone-like device during a call to Mercury Exchange Limited (MEL) Channel Associated Signaling (CAS). A voice signaling protocol used primarily in the United Kingdom.

PBX---Private branch exchange. Privately owned central switching office.

Permanent calls---Permanent calls are private line calls used for fixed point-to-point calls, connections between PBXs (E&M to E&M), or for remote telephone extensions (FXO to FXS).

PLAR---Private line, automatic ringdown. A leased voice circuit that connects two single endpoints together. When either telephone handset is taken off-hook, the remote telephone automatically rings.

POTS---Plain old telephone service. Basic telephone service supplying standard single line telephones, telephone lines, and access to the PSTN.

POTS dial peer---Dial peer connected via a traditional telephony network. POTS peers point to a particular voice port on a voice network device.

PSTN---Public Switched Telephone Network. PSTN refers to the local telephone company.

PVC---Permanent virtual circuit.

SVC---Switched virtual circuit.

Switched calls---Switched calls are normal telephone calls in which a user picks up a telephone, hears dial tone, enters the destination telephone number to reach the other telephone. Switched calls can also be private line auto-ringdown (PLAR) calls, or tie-line calls for fixed E&M to E&M fixed point-to-point connections.

Tandem switching---The dynamic switching of voice calls between VoFR or VoATM PVCs and subchannels; also called tandeming. Tandem switching is often encountered in multi-hop VoFR call connection paths.

Trunk---Service that allows quasi-transparent connections between two PBXs, a PBX and a local extension, or some other combination of telephony interfaces with signaling passed transparently through the packet data network.

VoFR---Voice over Frame Relay.

VoFR dial peer---Dial peer connected via a Frame Relay network. VoFR peers point to specific VoFR devices.

Voice over Frame Relay---Voice over Frame Relay enables a router to carry voice traffic (for example, telephone calls and faxes) over a Frame Relay network. When sending voice traffic over Frame Relay, the voice traffic is segmented and encapsulated for transit across the Frame Relay network by using FRF.12 encapsulation.

Posted: Sun May 21 10:48:01 PDT 2000
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