cc/td/doc/product/software/ios121/121cgcr/multi_c
hometocprevnextglossaryfeedbacksearchhelp
PDF

Table of Contents

Configuring Voice over ATM

Configuring Voice over ATM

This chapter shows you how to configure Voice over ATM (VoATM). This chapter contains the following sections:

VoATM enables a router to carry voice traffic (for example, telephone calls and faxes) over an ATM network. For a description of the commands used to configure VoATM, refer to the Cisco IOS Multiservice Applications Command Reference publication.


Note VoATM is supported only on the Cisco MC3810 in Cisco IOS Release 12.1. The Cisco MC3810 supports compressed VoATM on ATM port 0 only. When VoATM is enabled on the Cisco MC3810, the channel group, time-division multiplexing (TDM) group, and channel-associated signalling (CAS) functionality are not available on the Multiflex Trunk (MFT) because ATM uses all T1/E1 time slots.

Prerequisite Tasks

Before you can configure your router to use VoATM, you must first perform the following tasks:

After you have analyzed your dial plan and decided how to integrate it into your existing ATM network, you are ready to configure your network devices to support VoATM.

VoATM Configuration Task List

VoATM has a set of core tasks. To configure VoATM, perform the the tasks in the following sections:

Configuring Voice Ports on the Cisco MC3810

The Cisco MC3810 hardware features different hardware configuration options for voice ports:

Voice ports provide support for three basic voice signalling formats:

In general, voice-port commands define the characteristics associated with a particular voice-port signalling type. Under most circumstances, the default voice-port command values are adequate to configure FXO and FXS ports to transport voice data using the Cisco MC3810. Because of the inherent complexities involved with PBX networks, E&M ports might need specific voice-port values configured, depending on the specifications of the devices in your telephony network.

Table 28 lists the valid slot and port numbers for the different voice interfaces.


Table 28: Voice Interface Slot and Port Number
Interface Type Slot Valid Port Numbers

Analog voice module (AVM)

1

1-6

Digital voice module (DVM)

1

Digital T1: 1-24

Digital E1: 1-15 and 17-31

Multiflex Trunk (MFT)

0

Digital T1: 1-24

Digital E1: 1-15 and 17-31


Note The voice-port number designations start with 1. Unlike serial port interfaces and interfaces on other Cisco products, there is no port 0 for voice ports.

Configuring FXO or FXS Voice Ports on the Cisco MC3810

Under most circumstances the default voice-port values are adequate for both FXO and FXS voice ports. To configure FXO and FXS voice ports on the Cisco MC3810, use the following commands beginning in global configuration mode:

Command Purpose

Step 1

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

Identifies the voice port you want to configure and enters voice-port configuration mode.

Step2

Router(config-voiceport)# dial-type {pulse | dtmf}

(For FXO ports only) Selects the appropriate dial type for out-dialing. The default is dtmf.

Step3

Router(config-voiceport)# signal {loop-start | 
ground-start}

Configures the signalling type for analog FXO and FXS voice ports. The default is loop-start.

Step4

Router(config-voiceport)# compand-type {u-law | 
a-law}

(Digital voice ports only) Configures the companding standard used to convert between analog and digital signals in pulse code modulation (PCM) systems.

Step5

Router(config-voiceport)# cptone country

Configures the appropriate call progress tone for the local region.

The default for this command is us. For a list of supported countries, refer to the Cisco IOS Multiservice Applications Command Reference publication.

Step6

Router(config-voiceport)# ring number number

(For FXO ports only) Configures the number of rings detected before a connection is closed on the FXO port.

Step7

Router(config-voiceport)# ring frequency number

(For FXS ports only) Specifies the local ring frequency for the FXS voice port. The number value should be set to either 20 or 30.

Step8

Router(config-voiceport)# connection {plar| 
tie-line|plar-opx} string

Configures the voice-port connection mode type and the destination telephone number.

The plar value is used for private line auto ringdown (PLAR) connections. The tie-line value on the CiscoMC3810 is used for a tie-line connection to a PBX. The plar-opx value on the CiscoMC3810 is used for PLAR OPX, to allow the local voice port to provide a local response before the remote voice port receives an answer. If you select the plar-opx value, you must also configure the voice confirmation-tone command.


NoteIf you will be configuring Cisco switched trunk connections, do not configure this command now. See the "Configuring Cisco-Trunk Permanent Calls on a Cisco MC3810" section later in this chapter.

Step9

Router(config-voiceport)# description string

(Optional) Enters a string description for the voice port. The string describes the voice port in displays. You can use the description command to note the voice port location or use.

Step10

Router(config-voiceport)# codec {g729r8 | g729ar8 | 
g726r32 | g711alaw | g711ulaw}

((Optional for Cisco MC3810 only) Configures the voice-port compression mode. The g729ar8 value is the default and is recommended.

The g729ar8 compression mode can support a maximum of 24 simultaneously active on-net voice calls and the g729r8 value can only support a maximum of 12. The g729 compression modes have a nominal data rate of 8 kbps.

The Cisco MC3810 also supports configuring the codec command on the dial peer. Because the Cisco2600 and 3600 series routers support the codec command on the dial peer only, it is recommended you configure this command on the dial peer.

Step11

Router(config-voiceport)# vad

(Optional) Enables voice activity detection (VAD).


NoteThe Cisco MC3810 also supports configuring the vad command on the dial peer. Because the Cisco 2600 and 3600 series routers support the vad command on the dial peer only, it is recommended you configure this command on the dial peer.

Step12

Router(config-voiceport)# comfort-noise

(Optional) Specifies that background noise will be generated if you have VAD activated.

Step13

Router(config-voiceport)# voice confirmation-tone

(Optional) If the voice port is configured for connection plar-opx for OPX, disable the two-beep confirmation tone that a caller hears when picking up the handset.

Verifying the FXO and FXS Voice Port Configuration

You can verify your voice-port configuration by performing the following tasks:

Troubleshooting Tips

If you are having trouble connecting a call and you suspect the problem is associated with voice-port configuration, you can try to resolve the problem by performing the following tasks:

Fine-Tuning FXO and FXS Voice Ports on the Cisco MC3810

Depending on your particular network, you may need to adjust voice parameters involving timing, input gain, and output attenuation for FXO or FXS voice ports. Collectively, these commands are referred to as voice-port tuning commands.


NoteIn most cases, the default values for voice-port tuning commands will be sufficient.

To fine-tune FXO or FXS voice ports on the Cisco MC3810, use the following commands beginning in global configuration mode:

Command Purpose

Step1

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

Identifies the voice port you want to configure and enters voice-port configuration mode.

Step2

Router(config-voiceport)# input gain value

Specifies (in decibels) the amount of gain to be inserted at the receiver side of the interface. Acceptable values are from -6 to 14.

Step3

Router(config-voiceport)# output attenuation value

Specifies (in decibels) the amount of attenuation at the transmit side of the interface. Acceptable values are from 0 to 14.

Step4

Router(config-voiceport)# echo-cancel enable

Enables echo cancellation of voice that is sent out the interface and received back on the same interface.

Step5

Router(config-voiceport)# echo-cancel coverage value

Adjusts the size (in milliseconds) of the echo cancel. Acceptable values are 16, 24, and 32.

Step6

Router(config-voiceport)# timeouts initial seconds

Configures the initial timeout value. The initial timeout value specifies the number of seconds the system waits for the caller to input the first digit of the dialed digits. The default is 10 seconds.

Step7

Router(config-voiceport)# timeouts interdigit 
seconds

Configures the interdigit timeout value. The timeouts interdigit value specifies the number of seconds the system waits (after the caller has input the initial digit) for the caller to input a subsequent digit of the dialed digits. The default is 10 seconds.

Step8

Router(config-voiceport)# timing digit milliseconds

If the voice-port dial type is DTMF, configure the DTMF digit signal duration. The range of the DTMF digit signal duration is from 50to100 milliseconds. The default is 100.

Step9

Router(config-voiceport)# timing inter-digit 
milliseconds

If the voice-port dial type is DTMF, configure the DTMF interdigit signal duration. The range of the DTMF interdigit signal duration is from 50 to 500milliseconds. The default is 100.

Step10

Router(config-voiceport)# timing pulse-digit 
milliseconds

If the voice-port dial type is pulse, configure the pulse digit signal duration. The range of the pulse digit signal duration is from10 to 20 milliseconds. The default is 20.

Step11

Router(config-voiceport)# timing pulse-inter-digit 
milliseconds

If the voice-port dial type is pulse, configure the pulse interdigit signal duration. The range of the pulse interdigit signal duration is from 100 to 1000milliseconds. The default is 500.

Step12

Router(config-voiceport)# impedance {600r | 600c | 
900r | 900c}

(For FXO ports only) Configures the impedance. The default is 600 ohms real.

Step13

Router(config-voiceport)# loss-plan {plan1 | plan2 | 
plan3 | plan4 | plan7 | plan8 | plan9}

(For analog ports only) Specifies the loss plan for this voice port according to the signal level requirements for the DSP and the PBX. the default is plan1, which provides the following gain offset levels:

  • FXO---A-D gain = 0 dB, D-A gain = 0 dB

  • FXS---A-D gain = -3 dB, D-A gain = -3 dB

Step14

Router(config-voiceport)# ring cadence [on1 | off1] 
[on2 | off2] [on3|off3] [on4 | off4] [on5 | off5] 
[on6 | off6]

(For FXS ports only) Specifies the local ring cadence for the FXS voice port. Using this command, specify the on and off pulses for the ring. The ring cadence differs depending on the local region. The units are in 100-millisecond units.


NoteAfter you change any voice-port command, it is a good idea to cycle the port by using the shutdown and no shutdown commands.

Configuring E&M Voice Ports on the Cisco MC3810

Unlike FXO and FXS voice ports, the default E&M voice-port parameters most likely will not be sufficient to enable voice data transmission over your network.


NoteE&M voice-port values must match those of the PBX to which it is connected. Refer to the documentation that came with your specific PBX for the appropriate E&M voice-port configuration command values.

To configure E&M voice ports on the Cisco MC3810, use the following commands beginning in global configuration mode:

Command Purpose

Step1

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

Identifies the voice port you want to configure and enters voice-port configuration mode.

Step2

Router(config-voiceport)# connection 
{plar|tie-line|plar-opx} string

Configures the voice-port connection mode type and the destination telephone number.

The plar value is used for private line auto ringdown (PLAR) connections. The tie-line value on the CiscoMC3810 is used for a tie-line connection to a PBX. The plar-opx value on the CiscoMC3810 is used for PLAR OPX, to allow the local voice port to provide a local response before the remote voice port receives an answer. If you select the plar-opx value, you must also configure the voice confirmation-tone command.


NoteIf you will be configuring Cisco switched trunk connections, do not configure this command now. See the "Configuring Cisco-Trunk Permanent Calls on a Cisco MC3810" section later in this chapter.

Step3

Router(config-voiceport)# dial-type dtmf

Selects the appropriate dial type for out-dialing. For E&M voice ports, the only available choice is DTMF.

Step4

Router(config-voiceport)# operation {2-wire | 
4-wire}

Selects the appropriate cabling scheme for this voice port.

Step5

Router(config-voiceport)# type {1 | 2 | 3 | 5}

Selects the appropriate E&M interface type.

Type 1 indicates the following lead configuration:

E---output, relay to ground
M---input, referenced to ground

Type 2 indicates the following lead configuration:

E---output, relay to SG
M---input, referenced to ground
SB---feed for M, connected to -48V
SG---return for E, galvanically isolated from ground

Type 3 indicates the following lead configuration:

E---output, relay to ground
M---input, referenced to ground
SB---connected to -48V
SG---connected to ground

Type 5 indicates the following lead configuration:

E---output, relay to ground
M---input, referenced to -48V.

Step6

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

Configures the signalling type for E&M voice ports. The default is wink start.

Step7

Router(config-voiceport)# codec {g729r8 | g729ar8}

or

Configures the voice-port compression mode. The g729ar8 value is the default and is recommended.

The g729ar8 compression mode can support a maximum of 24 simultaneously active on-net voice calls and the g729r8 value can only support a maximum of 12. Both compression modes have a nominal data rate of 8 kbps.

Router(config-voiceport) codec {g726r32 | g711alaw | 
g711ulaw}

or configure the fax rate dial-peer command. See the "Configuring VoATM Dial Peers" section later in this chapter.

(Fax only, Optional) If you are configuring a dial peer for faxes over ATM switched virtual circuits (SVCs), the default codec setting for the voice port does not function properly with the typical fax rate of 9600bps. Therefore, you can either change the codec or change the fax rate. The codec must support a minimum of 22 kbps.

To change the codec from the default g729ar8 codec (8kbps), enter the voice-port codec command to specify one of the following compression modes:

  • g726r32---Specifies G.726 32K ADCPM compression.

  • g711alaw---Specifies G.711 64K PCM A-Law compression.

  • g711ulaw---Specifies G.711 64K PCM U-Law compression.


NoteThe Cisco MC3810 also supports configuring the codec command on the dial peer as well. Because the Cisco 2600 and 3600 series routers support the codec command on the dial peer only, it is recommended you configure the codec command on the dial peer.

Step8

Router(config-voiceport)# compand-type {u-law | 
a-law}

(Digital voice ports only) Configures the companding standard used to convert between analog and digital signals in PCM systems.

Step9

Router(config-voiceport)# cptone country

Configures the appropriate call progress tone for the local region.

The default for this command is us. For a list of supported countries, refer to the Cisco IOS Multiservice Applications Command Reference publication.

Step10

Router(config-voiceport)# description string

(Optional) Attaches descriptive text about this voiceport connection.

Step11

Router(config-voiceport)# vad

(Optional) Enables VAD on the voice port.


NoteThe Cisco MC3810 also supports configuring the vad command on the dial peer. Because the Cisco 2600 and 3600 series routers support the vad command on the dial peer only, it is recommended you configure this command on the dial peer.

Step12

Router(config-voiceport)# voice confirmation-tone

(Optional) If the voice port is configured for connection plar-opx for OPX, disable the two-beep confirmation tone that a caller hears when picking up the handset.

Verifying the E&M Voice Port Configuration

You can verify your voice-port configuration by performing the following tasks:

Troubleshooting Tips

If you are having trouble connecting a call and you suspect the problem is associated with voice-port configuration, you can try to resolve the problem by performing the following tasks:

Fine-Tuning E&M Voice Ports on the Cisco MC3810

Depending on the specifics of your particular network, you may need to adjust voice parameters involving timing, input gain and output attenuation for E&M voice ports. Collectively, these commands are referred to as voice-port tuning commands.


NoteIn most cases, the default values for voice-port tuning commands will be sufficient.

To fine-tune E&M voice ports on the Cisco MC3810, use the following commands beginning in global configuration mode:

Command Purpose

Step1

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

Identifies the voice port you want to configure and enters voice-port configuration mode.

Step2

Router(config-voiceport)# input gain value

Specifies (in decibels) the amount of gain to be inserted at the receiver side of the interface. Acceptable values are from -6 to 14.

Step3

Router(config-voiceport)# output attenuation value

Specifies (in decibels) the amount of attenuation at the transmit side of the interface. Acceptable values are from 0 to 14.

Step4

Router(config-voiceport)# echo-cancel enable

Enables echo cancellation of voice that is sent out the interface and received back on the same interface.

Step5

Router(config-voiceport)# echo-cancel coverage value

Adjusts the size (in milliseconds) of the echo cancel. Acceptable values are 16, 24, and 32.

Step6

Router(config-voiceport)# non-linear

Enables nonlinear processing, which shuts off any signal if no near-end speech is detected. (Nonlinear processing is used with echo cancellation.)

Step7

Router(config-voiceport)# timeouts initial seconds

Configures the initial timeout value. The initial timeout value specifies the number of seconds the system waits for the caller to input the first digit of the dialed digits. The default is 10 seconds.

Step8

Router(config-voiceport)# timeouts interdigit 
seconds

Configures the interdigit timeout value. The timeouts interdigit value specifies the number of seconds the system waits (after the caller has input the initial digit) for the caller to input a subsequent digit of the dialed digits. The default is 10 seconds.

Step9

Router(config-voiceport)# timeouts wait-release 
{value | infinity}

Configures the timeout value for releasing voice ports. This command limits the duration that a voice port stays in the call failure state while the Cisco MC3810 sends a busy tone, reorder tone or out-of-service tone to the port.

Step10

Router(config-voiceport)# timing digit milliseconds

If the voice-port dial type is DTMF, configures the DTMF digit signal duration. The range of the DTMF digit signal duration is from 50to100 milliseconds. The default is 100.

Step11

Router(config-voiceport)# timing inter-digit 
milliseconds

If the voice-port dial type is DTMF, configures the DTMF interdigit signal duration. The range of the DTMF interdigit signal duration is from 50 to 500milliseconds. The default is 100.

Step12

Router(config-voiceport)# timing pulse-digit 
milliseconds

If the voice-port dial type is pulse, configures the pulse digit signal duration. The range of the pulse digit signal duration is from 10 to 20 milliseconds. The default is 20.

Step13

Router(config-voiceport)# timing pulse-inter-digit 
milliseconds

If the voice-port dial type is pulse, configures the pulse interdigit signal duration. The range of the pulse interdigit signal duration is from 100 to 1000milliseconds. The default is 500.

Step14

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

Configures the timing wink-duration value. This value sets the wink signal duration for a wink-start signal. This value applies only if the signal command is set to "wink-start." The range is from 100 to 400milliseconds and the default is 200.

Step15

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

Configures the timing wink-wait value. This value sets the wink wait duration for a wink-start signal. This value applies only if the signal command is set to "wink-start." The range is from 100 to 5000milliseconds and the default is 200.

Step16

Router(config-voiceport)# timing clear-wait 
milliseconds

Configures the timing clear-wait value. This value sets the amount of time between the inactive seizure signal and the call being cleared. The range is from 100 to 2000 milliseconds and the default is 400.

Step17

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

Configures the timing delay-duration value. This value sets the delay signal duration for delay dial signalling. This value applies only if the signal command is set to "delay-dial." The range is from 100 to 5000 milliseconds and the default is 140.

Step18

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

Configures the timing delay-start value. This value sets the delay interval between the generation of the delay-start signal from incoming detection seizure. This value applies only if the signal command is set to "delay-dial." The range is from 100 to 290milliseconds and the default is 150.

Step19

Router(config-voiceport)# timing percentbreak 
percent

Configures the timing percent-break value. This value sets the percentage of the break period for a dialing pulse. The default is 50 percent.


NoteAfter you change any voice-port command, it is a good idea to cycle the port by using the shutdown and no shutdown commands.

Activating the Voice Port

After you have configured the voice port, you need to activate the voice port to bring it online. In fact it is a good idea to cycle the port---meaning to shut the port down and then bring it online again.

To activate a voice port, use the following command in voice-port configuration mode:

Command Purpose
Router(config-voiceport)# no shutdown

Activates the voice port.

To cycle a voice port, use the following commands in voice-port configuration mode:

Command Purpose

Step1

Router(config-voiceport)# shutdown

Deactivates the voice port.

Step2

Router(config-voiceport)# no shutdown

Activates the voice port.

:


NoteIf you will not use a voice port, shut it down.

Configuring ATM PVCs for VoATM

This section describes the preliminary ATM configuration tasks necessary to support VoATM PVCs. The commands and procedures in this section are specific to the Cisco MC3810.


NoteIf any CAS groups, channel groups, or clear channels are configured on T1/E1 controller 0 on the Cisco MC3810, you must remove them before configuring VoATM. Because ATM requires all DS0s, if any DS0s on controller 0 are used by other applications, the ATM configuration cannot take place.

To configure the Cisco MC3810 to support VoATM PVCs on the T1/E1 trunk, use the following commands beginning in global configuration mode:

Command Purpose

Step1

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

Selects T1/E1 controller 0. ATM is supported only on controller 0 on the Cisco MC3810.

Step2

Router(config-controller)# mode atm

Specifies that the controller will support ATM encapsulation, and to create virtual ATM interface 0, which you will use to create the ATM PVCs.

When the controller is set to ATM mode, the following takes place:

  • The controller framing is automatically set to Extended Superframe (ESF) on T1 and to CRC4 on E1. The line code is automatically set to B8ZS on T1 and to HDB3 on E1.

  • Channel groups, CAS groups, common channel signalling (CCS) groups, or clear channels are not allowed on the trunk because ATM traffic occupies all the DS0s.

Step3

Router(config-controller)# no shutdown

Activates the controller.

Step4

Router(config-controller)# exit

Exits controller configuration mode.

Step5

Router(config)# interface atm0 {multipoint | 
point-to-point}

Enters interface configuration mode to configure ATM interface 0.

If the VoATM connection will be over a point-to-point network, specify the point-to-point option. The default option, multipoint, assumes you have a fully meshed network.

Step6

Router(config-if)# ip address ip-address mask

Assigns the IP address and subnet mask to the interface.

Step7

Router(config-if)# pvc [name] vpi/vci

Creates an ATM PVC for voice traffic and enters virtual circuit configuration mode.

Step8

Router(config-if-atm-pvc)# encapsulation aal5mux 
voice

Set the encapsulation of the PVC to support voice traffic.


NoteTo configure a PVC to support data traffic, use aal5snap encapsulation.

Step9

Router(config-if-atm-pvc)# vbr-rt peak-rate 
average-rate [burst]

Configures the peak rate, average rate, and the burst cell size to perform traffic shaping between voice and data PVCs. The vbr-rt command configures the VBR for real-time networks such as for voice networks.

For more information on how to calculate the vbr-rt command values, see the "Calculating the VBR Real-Time Options for Traffic Shaping" section later in this chapter.

Step10

Router(config-if-atm-pvc)# exit

Exits ATM virtual circuit configuration mode.

The only commands in ATM virtual circuit configuration mode used for ATM voice PVCs are encapsulation aal5mux voice, vbr-rt, and ilmi.

Repeat Steps 7 through 10 for each ATM voice PVC you want to configure. When you have completed configuring all the ATM voice PVCs, continue with Steps 11 through 14.

Step11

Router(config-if)# pvc [name] vpi/vci

Creates an ATM PVC for data traffic and enters PVC configuration mode.

Step12

Router(config-if-atm-pvc)# encapsulation aal5snap

Set the encapsulation of the PVC to support ATM data traffic. In ATM PVC configuration mode, configure either the ubr, ubr+, or the vbr-nrt traffic shaping commands for the data PVC as appropriate.

Step13

Router(config-if-atm-pvc)# exit

Exits ATM virtual circuit configuration mode. Repeat Steps 11 and 12 for each data PVC configured.

Step14

Router(config-if)# exit

Exits interface configuration mode.

The VoATM configuration must be performed on the routers on both sides of the voice connection.


NoteWhen verifying your ATM PVC connectivity, note that you cannot issue the ping command over a voice PVC because the command applies to data only. If you have data and voice PVCs set to the same destination, you can issue the ping command over the data PVC.

Calculating the VBR Real-Time Options for Traffic Shaping

The vbr-rt command configures the VBR for real-time networks such as for voice networks. This command performs traffic shaping between voice and data PVCs. Traffic shaping is necessary so that the carrier does not discard the incoming calls from the CiscoMC3810. To configure voice and data traffic shaping, you must configure the peak, average, and burst options for voice traffic. Configure the burst value if the PVC will be carrying bursty traffic. The peak, average, and burst values are needed so the PVC can effectively handle the bandwidth for the number of voice calls. To calculate the minimum peak, average, and burst values for the number of voice calls, use the following calculations:

The peak value equals the Peak Information Rate (PIR).
The average value equals the Average Information Rate (AIR). This value correlates to the carrier's sustainable cell rate (SCR).
The burst value is the burst size in cells.

NoteWhen you configure data PVCs that will be traffic shaped with voice PVCs, use the aal5snap encapsulation and calculate the overhead as 1.13 times the voice rate.

Configuring ATM SVCs for VoATM

In this section, the ATM interface is set up, including PVCs to carry signalling for SVCs. In addition, you specify a network service access point (NSAP) address for the ATM SVC. The Cisco IOS Wide-Area Networking Configuration Guide and Cisco IOS Wide-Area Networking Command Reference publications provide additional information about this and other aspects of ATM configuration.

To configure ATM SVCs to support VoATM, use the following commands beginning in global configuration mode:

Command Purpose

Step1

Router(config)# interface atm 0 
[.subinterface-number {multipoint | point-to-point}]

Configures the ATM interface.

Optionally, you can create and configure a subinterface. This is useful when you wish to configure an extra parameter on the ATM interface. For example, you can specify one IP address on the main interface, as shown in Step 2; then you can configure a second IP address on a subinterface.

The subinterface-number argument is a value in the range from 1 to 4294967293.

Enter the multipoint keyword when your network is fully meshed and you want to communicate with multiple routers. The point-to-point keyword configures the subinterface for communication with one router, as in a hard-wired connection.

Step2

Router(config-if)# ip address ip-address mask

Assigns the IP address and subnet mask to the interface.

Step3

Router(config-if)# atm voice aesa {default | 
esi-address}

This command sets the unique ATM end-station address (AESA) for an ATM interface that is using SVC mode for voice.

The default keyword automatically creates an NSAP address for the interface, based on a prefix from the ATM switch (26 hexadecimal characters), the MAC address (12hexadecimal characters) as the end station identifier (ESI), and a selector byte (two hexadecimal characters).

The esi-address option requires that you enter 12 hexadecimal characters as the ESI. The ATM switch provides the prefix and the voice selector byte provides the remaining characters.

You can view the assigned address using the show atm video-voice address command.

Step4

Router(config-if)# pvc [name] vpi/vci ilmi 

Creates an ATM permanent virtual circuit (PVC) for ILMI management purposes and enters PVC configuration mode.

The optional name argument is a unique label that can be up to 16 characters long. The name argument identifies to the processor the virtual path identifier-virtual channel identifier (VPI-VCI) pair to use for a particular packet.

The ATM network VPI of this PVC is an 8-bit field in the header of the ATM cell. The vpi value is unique only on a single link, not throughout the ATM network, because it has local significance only. The vpi value must match that of the switch. Valid values are from 0 to 255, but the value is usually 0 for ILMI communications. If not specified, the vpi value is set to 0.

You cannot set both vpi and vci to 0; if one is 0, the other cannot be 0.

For ILMI communications the VCI value is typically 16. The VCI is a 16-bit field in the header of the ATM cell. The VCI value is unique only on a single link---not throughout the ATM network---because it has local significance only.

To set up communication with the ILMI, enter a value of ilmi for ATM adaptation layer (AAL) encapsulation; the associated vpi and vci values are typically 0 and 16, respectively.


NoteTypically, the low values 0 to 31 are reserved for specific traffic (for example, F4 OAM, SVC signalling, ILMI, and so on) and you should not use them for other PVCs.

Step5

Router(config-if-atm-pvc)# pvc [name] vpi/vci qsaal 

See the explanations in Step 4 for the name, vpi, and vci values.

To enable the signalling for setup and tear-down of SVCs, specify the Q.SAAL (signalling ATM adaptation layer) encapsulation; the associated vpi and vci values are typically 0 and 5, respectively. You cannot create this PVC on a subinterface.

Step6

Router(config-if-atm-pvc)# exit

Exits PVC interface configuration mode.

Verifying the ATM Interface Configuration

To verify the ATM interface configuration, perform the following steps:


Step 1 To see how SVCs and PVCs are set up, enter the privileged EXEC show atm vc command, as in the following example:

Router# show atm vc
VCD /                                      Peak  Avg/Min Burst
Interface   Name       VPI   VCI  Type   Encaps   SC   Kbps   Kbps   Cells  Sts
0          1            0     5   PVC    SAAL     UBR       0                UP
0          2            0    16   PVC    ILMI     UBR       0                UP
0          379          0    60   SVC    SNAP     UBR       0                UP
0          986          0    84   SVC    SNAP     UBR       0                UP
0          14           0   133   SVC    VOICE    VBR      64     16   10    UP
0          15           0   134   SVC    VOICE    VBR      64     16   10    UP
0          16           0   135   SVC    VOICE    VBR      64     16   10    UP
0          17           0   136   SVC    VOICE    VBR      64     16   10    UP
0          18           0   137   SVC    VOICE    VBR      64     16   10    UP
0          19           0   138   SVC    VOICE    VBR      64     16   10    UP
0          20           0   139   SVC    VOICE    VBR      64     16   10    UP
0          21           0   140   SVC    VOICE    VBR      64     16   10    UP
0          22           0   141   SVC    VOICE    VBR      64     16   10    UP
0          23           0   142   SVC    VOICE    VBR      64     16   10    UP
0          24           0   143   SVC    VOICE    VBR      64     16   10    UP
0          25           0   144   SVC    VOICE    VBR      64     16   10    UP
0          26           0   145   SVC    VOICE    VBR      64     16   10    UP
0          27           0   146   SVC    VOICE    VBR      64     16   10    UP
0          28           0   147   SVC    VOICE    VBR      64     16   10    UP
 

Step 2 Enter the show atm svc command with or without the VPI/VCI specified. The following example shows information for a specific SVC:

Router# show atm svc 0/134
 
ATM0: VCD: 5, VPI: 0, VCI: 134
VBR, PeakRate: 64000
AAL5, etype: 0x0, Flags 0x440, VCmode: 0xE000
OAM frequency: 0 second(s), OAM retry frequency: 1 second(s)
OAM up retry count: 3, OAM down retry count: 5
OAM Loopback status: OAM Disabled
OAM VC state: Not Managed
ILMI VC state: Not Managed
InARP DISABLED
InPkts: 4, OutPkts: 4, InBytes: 432, OutBytes: 432
InPRoc: 4, OutPRoc: 4, Broadcasts: 0
InFast: 0, OutFast: 0, InAS: 0, OutAS: 0
OAM cells received: 0
F5 InEndloop: 0, F5 InSegloop: 0, F5 InAIS: 0, F5 InRDI:0
F4 InEndloop: 0, F4 InSegloop: 0, F4 InAIS: 0, F4 InRDI:0
OAM cells sent: 0
F5 OutEndloop: 0, F5 OutSegloop: 0, F5 OutRDI: 0
OAM cell drops: 0
Status: UP
TTL: 3
interface = ATM0, call locally initiated, call reference = 5558610
vcnum = 5, vpi = 0, vci = 134, state = Active(U10), point-to-point call
Retry count: Current = 0
timer currently inactive, timer value = 00:00:00
Remote Atm Nsap address:47.00918100000000400B0A2501.0060837B4743.00, VCowner:Static Map
 

Step 3 To learn which PVCs are set up for ILMI management and Q.SAAL signalling, enter the show atm pvc command with the VPI/VCI specified, as in the following example:

Router# show atm pvc 0/5
ATM0: VCD: 2, VPI: 0, VCI: 5, Connection Name: SAAL
UBR, PeakRate: 56
AAL5-SAAL, etype:0x4, Flags: 0x26, VCmode: 0x0
OAM frequency: 0 second(s), OAM retry frequency: 1 second(s), OAM retry frequenc
y: 1 second(s)
OAM up retry count: 3, OAM down retry count: 5
OAM Loopback status: OAM Disabled
OAM VC state: Not Managed
ILMI VC state: Not Managed
InARP DISABLED
InPkts: 2044, OutPkts: 2064, InBytes: 20412, OutBytes: 20580
InPRoc: 2044, OutPRoc: 2064, Broadcasts: 0
InFast: 0, OutFast: 0, InAS: 0, OutAS: 0
OAM cells received: 0
F5 InEndloop: 0, F5 InSegloop: 0, F5 InAIS: 0, F5 InRDI: 0
F4 InEndloop: 0, F4 InSegloop: 0, F4 InAIS: 0, F4 InRDI: 0
OAM cells sent: 0
F5 OutEndloop: 0, F5 OutSegloop: 0, F5 OutRDI: 0
F4 OutEndloop: 0, F4 OutSegloop: 0, F4 OutRDI: 0
OAM cell drops: 0
Compress: Disabled
Status: INACTIVE, State: NOT_IN_SERVICE
!
Router# show atm pvc 0/16
ATM0: VCD: 1, VPI: 0, VCI: 16, Connection Name: ILMI
UBR, PeakRate: 56
AAL5-ILMI, etype:0x0, Flags: 0x27, VCmode: 0x0
OAM frequency: 0 second(s), OAM retry frequency: 1 second(s), OAM retry frequenc
y: 1 second(s)
OAM up retry count: 3, OAM down retry count: 5
OAM Loopback status: OAM Disabled
OAM VC state: Not Managed
ILMI VC state: Not Managed
InARP DISABLED
InPkts: 398, OutPkts: 421, InBytes: 30493, OutBytes: 27227
InPRoc: 398, OutPRoc: 421, Broadcasts: 0
InFast: 0, OutFast: 0, InAS: 0, OutAS: 0
OAM cells received: 0
F5 InEndloop: 0, F5 InSegloop: 0, F5 InAIS: 0, F5 InRDI: 0
F4 InEndloop: 0, F4 InSegloop: 0, F4 InAIS: 0, F4 InRDI: 0
OAM cells sent: 0
F5 OutEndloop: 0, F5 OutSegloop: 0, F5 OutRDI: 0
F4 OutEndloop: 0, F4 OutSegloop: 0, F4 OutRDI: 0
OAM cell drops: 0
Compress: Disabled
Status: INACTIVE, State: NOT_IN_SERVICE

Step 4 To view information about the ATM interface, enter the privileged EXEC show atm interface command and specify ATM 0, as in the following example:

Router# show interface atm 0
ATM0 is up, line protocol is up
  Hardware is PQUICC Atom1
  Internet address is 9.1.1.6/8
  MTU 1500 bytes, sub MTU 1500, BW 1536 Kbit, DLY 20000 usec,
     reliability 255/255, txload 22/255, rxload 11/255
  NSAP address: 47.0091810000000002F26D4901.000011116666.06
  Encapsulation ATM
  292553397 packets input, -386762809 bytes
  164906758 packets output, 1937663833 bytes
  0 OAM cells input, 0 OAM cells output, loopback not set
  Keepalive not supported
  Encapsulation(s):, PVC mode
  1024 maximum active VCs, 28 current VCCs
  VC idle disconnect time: 300 seconds
  Signalling vc = 1, vpi = 0, vci = 5
  UNI Version = 4.0, Link Side = user
  Last input 00:00:00, output 2d05h, output hang never
  Last clearing of "show interface" counters never
  Input queue: -1902/75/0 (size/max/drops); Total output drops: 205
  Queueing strategy: weighted fair
  Output queue: 0/1000/64/0 (size/max total/threshold/drops)
     Conversations  0/0/256 (active/max active/max total)
     Reserved Conversations 0/0 (allocated/max allocated)
  5 minute input rate 67000 bits/sec, 273 packets/sec
  5 minute output rate 136000 bits/sec, 548 packets/sec
     76766014 packets input, 936995443 bytes, 0 no buffer
     Received 0 broadcasts, 0 runts, 0 giants, 0 throttles
     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
     367264676 packets output, 3261882795 bytes, 0 underruns
     0 output errors, 0 collisions, 2 interface resets
     0 output buffer failures, 0 output buffers swapped out
 

Step 5 Enter the show atm video-voice address privileged EXEC command to see information about the ATM interface address, which is particularly helpful because the address is assigned automatically with the atm voice aesa command. The following display also confirms that the ILMI status is confirmed---the ILMI PVC is set up to allow SVC management:

Router# show atm video-voice address
nsap address                                  type         ilmi status
47.0091810000000002F26D4901.00107B4832E1.FE   VOICE_AAL5   Confirmed
47.0091810000000002F26D4901.00107B4832E1.C8   VIDEO_AAL1   Confirmed

Troubleshooting VoATM SVCs

When problems occur with voice over ATM SVCs, perform the following steps to look first for simpler problems before progressing to more complex possible issues:


Step 1 Make sure that the ATM interface, serial ports, and controllers are set to no shutdown.

Step 2 On both Cisco MC3810 multiservice access concentrators, make sure that ILMI and Q.SAAL PVCs are set up in order to allow SVC communications. The show atm pvc command displays information about configured PVCs, including the ILMI and Q.SAAL PVCs.

Router# show atm pvc
 VCD /                                      Peak  Avg/Min Burst
Interface   Name       VPI   VCI  Type   Encaps   SC   Kbps   Kbps   Cells  Sts
0          1            0     5   PVC    SAAL     UBR       56               UP
0          2            0    16   PVC    ILMI     UBR       56               UP
 

Step 3 Ensure that NSAP addresses are set up and confirmed as operational under the ATM interfaces of the Cisco MC3810 multiservice access concentrators on both sides of the communication. Enter the show atm video-voice address or show atm ilmi-status privileged EXEC commands, which are shown in the following example. The show atm ilmi-status command provides more details about the ILMI PVC than does show atm video-voice address command:

router# show atm video-voice address
nsap address                                  type         ilmi status
47.0091810000000002F26D4901.00107B4832E1.FE   VOICE_AAL5   Confirmed
 
router# show atm ilmi-status
 
Interface : ATM0 Interface Type : Private UNI (User-side)
ILMI VCC : (0, 16) ILMI Keepalive : Enabled (5 Sec 4 Retries)
ILMI State:       UpAndNormal
Peer IP Addr:     10.1.1.11       Peer IF Name:     ATM1/0/0
Peer MaxVPIbits:  8               Peer MaxVCIbits:  14
Active Prefix(s) :
47.0091.8100.0000.0002.f26d.4901
End-System Registered Address(s) :
47.0091.8100.0000.0002.f26d.4901.0000.1111.5555.05(Confirmed)
47.0091.8100.0000.0002.f26d.4901.0010.7b48.32e1.fe(Confirmed)
47.0091.8100.0000.0002.f26d.4901.0010.7b48.32e1.c8(Confirmed)
 

Step 4 Check the voice ports for busyout status by entering the show voice busyout command. If the busyout-monitor interface or busyout forced command has been issued, one or more voice ports may be busied out, either due to a serial interface failure or because the voice port has been forced into a busyout state.

router# show voice busyout
If following network interfaces are down, voice port will be put into busyout state Serial0
The following voice ports are in busyout state 1/10
 

Enter the show interfaces serial command to check the specified serial interface, or enter the show voice port command to check the voice port status. The no form of the busyout forced command restores the voice port.

Step 5 Check for clocking problems. Enter the show controllers t1 command or the show controllers e1 command to check for slip errors, as shown in the following excerpt from the command output:

 .
 .
 .
 Data in current interval (819 seconds elapsed):
     0 Line Code Violations, 0 Path Code Violations
     0 Slip Secs, 0 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins
     0 Errored Secs, 0 Bursty Err Secs, 0 Severely Err Secs, 0 Unavail Secs
  Data in Interval 1:
     0 Line Code Violations, 0 Path Code Violations
     0 Slip Secs, 0 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins
     0 Errored Secs, 0 Bursty Err Secs, 0 Severely Err Secs, 0 Unavail Secs
  Data in Interval 2:
     0 Line Code Violations, 0 Path Code Violations
     0 Slip Secs, 0 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins
     0 Errored Secs, 0 Bursty Err Secs, 0 Severely Err Secs, 0 Unavail Secs
  Data in Interval 3:
     0 Line Code Violations, 0 Path Code Violations
     0 Slip Secs, 0 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins
     0 Errored Secs, 0 Bursty Err Secs, 0 Severely Err Secs, 0 Unavail Secs
   .

A few slip errors may not indicate a problem with clocking. However, if there are numerous errors, especially incrementing numbers of errors, you should check the following possibilities:

Step 6 Check the functionality of the Service-Specific Connection-Oriented Protocol (SSCOP). Enter the privileged EXEC show sscop command. See the following excerpt from the command output:

router# show sscop
SSCOP details for interface ATM0
   Current State = Data Transfer Ready
 

Interpretation of the command output requires familiarity with SSCOP, so unless you understand the protocol, just use the command to ensure that the protocol is in a state of readiness, as shown in the example. If you need to make changes, see the Cisco IOS Wide-Area Networking Configuration Guide and the Cisco IOS Wide-Area Networking Command Reference publications.


NoteIf you plan to adjust SSCOP parameters, you may wish to complete the rest of the troubleshooting steps before taking this route.

Step 7 To verify that each dial peer has been configured properly to communicate with the other, enter the show dial-peer voice command on the local and remote concentrators, as shown in the following example:

Router1# show dial-peer voice
VoiceEncapPeer33
        tag = 1, destination-pattern = `5558810',preference = 0,
        Admin state is up, Operation state is up
        type = pots, prefix = `',       fwd-digits = 0,
        session-target = `', voice-port = 1/1
VoiceOverATMPeer333
        tag = 2, destination-pattern = `559...',preference = 0,
        Admin state is up, Operation state is up
        type = voatm, session-target = 'ATM0'
        nsap '47.0091810000000002F26D4901.567856785678.56',
 
Router2# show dial-peer voice
VoiceEncapPeer44
        tag = 20, destination-pattern = `5559810',preference = 0,
        Admin state is up, Operation state is up
        type = pots, prefix = `',       fwd-digits = 0,
        session-target = `', voice-port = 1/1
VoiceOverATMPeer444
        tag = 10, destination-pattern = `5558...',preference = 0,
        Admin state is up, Operation state is up
        type = voatm, session-target = 'ATM0'
        nsap '47.0091810000000002F26D4901.100110011001.01',
 

Step 8 To see information about current and recent voice calls, allowing analysis of possible problems, enter the show call history voice record privileged EXEC command:

router# show call history voice record 
ConnectionId=[0x9CE20881 0x224855C1 0x0 0x1C9B84C7]
Media=TELE, TxDuration= 301962 ms
CallingNumber=6668808
SetupTime=47995411 x 10ms
ConnectTime=47995671 x 10ms
DisconectTime=48025867 x 10ms
DisconnectText=local onhook
 
ConnectionId=[0x9CE20881 0x224855C1 0x0 0x1C9B84C7]
Media=ATM, LowerIfName=ATM0, VPI=0, VCI=299
CalledNumber=5559808
SetupTime=47995483 x 10ms
ConnectTime=47995671 x 10ms
DisconectTime=48025867 x 10ms
DisconnectText=remote onhook
 
ConnectionId=[0x9CE20881 0x224855C2 0x0 0x1C9B84CB]
Media=TELE, TxDuration= 301950 ms
CallingNumber=5558803
SetupTime=47995412 x 10ms
ConnectTime=47995682 x 10ms
DisconectTime=48025877 x 10ms
DisconnectText=local onhook

Preparing to Configure Voice Dial Peers

After you have analyzed your dial plan and decided how to integrate it into your existing network, you are ready to configure your network devices to support VoATM. The actual configuration procedure depends on the topology of your voice network, but in general you need to perform the tasks in the following sections:


TimeSaverYou might want to configure the ATM dial peers in a back-to-back configuration before separating them across the ATM network. Using a back-to-back configuration, you can test your VoATM and dial-peer configuration to learn if you can successfully make a voice connection. Then, when you place both peers on the network, if you cannot make a voice connection you can isolate the cause as a network problem. For an example of a back-to-back voice over ATM configuration, refer to the "VoATM Configuration Examples" section later in this chapter.

Organizing Voice Network Information

After you have merged your telephony and WAN networks, there are tasks you can perform to simplify configuring VoATM. One task is to collect all of the information directly related to each dial peer by creating a peer configuration table.

Creating a Peer Configuration Table

Specific information relative to each dial peer needs to be identified before you can configure VoATM. One way to do this is to create a peer configuration table.

Figure 85 shows a diagram of a small voice network in which Router 1, with ATM virtual circuit 20, connects a small sales branch office to the main office through Router 2. Only two devices in the sales branch office need to be established as dial peers: a basic telephone and a fax machine. Router 2, with an ATM virtual circuit of 40, is the primary gateway to the main office; as such, it needs to be connected to the company PBX. Three devices need to be established as dial peers in the main office, all of which are basic telephones connected to the PBX.

Table 29 shows the peer configuration table for the example illustrated in Figure 85.


Figure85: Sample VoATM Network



Table29: Peer Configuration Table for Sample VoATM Network
Dial Peer Extension Prefix Destination-
Pattern
Type Voice Port Session Target
Router 1

1

61111

---

+13101161111

POTS

1/1

---

2

62222

---

+13101162222

POTS

1/2

---

10

---

---

+1310117....

VoATM

---

S2 20

Router 2

11

---

---

+1310116....

VoATM

---

S2 40

3

73333

7

+1310117....

POTS

1/1

---

4

74444

7

+1310117....

POTS

1/1

---

5

75555

7

+1310117....

POTS

1/1

---

The dial plan shown in Table 29 lists a simple dial-peer configuration table, with no special configuration for how you forward or play out excess digits. For more information on other options for designing your dial plan and configuring your dial peers to connect with PBXs, see the "Dial Planning and Dial-Peer Digit Manipulation Options" section in the "Configuring Voice over Frame Relay" chapter. The concepts described in that chapter also apply to VoATM.

Configuring Dial Peers

Dial peers describe the entities to and from which a call is established. Dial-peer configuration tasks define the address or set of addresses serviced by that dial peer and the call parameters required to establish a call to and from that dial peer.

The following two different kinds of dial peers pertain to VoATM:

POTS dial peers associate a telephone number with a particular voice port so that incoming calls for that telephone number can be received. VoATM dial peers point to specific voice-network devices (by associating destination telephone numbers with a specific ATM virtual circuit) so that outgoing calls can be placed. Both POTS and VoATM dial peers are required if you want to both send and receive calls using VoATM.

Establishing two-way communication using VoATM requires establishing a specific voice connection between two defined endpoints. As shown in Figure 86, for outgoing calls (from the perspective of the POTS dial peer 1), the POTS dial peer establishes the source (the originating telephone number and voice port) of the call. The VoATM dial peer establishes the destination by associating the destination phone number with a specific ATM virtual circuit.


Figure86: Calls from the Perspective of Cisco MC3810 No. 1


In the example, the destination pattern 14085554000 string maps to a U.S. phone number 555-4000, with the digit 1 plus the area code (408) preceding the number. When you configure the destination pattern, set the dial string to match the local dial conventions.

To complete the two-way communications loop, you need to configure VoATM dial peer 2 as shown in Figure 87.


Figure87: Calls from the Perspective of Cisco MC3810 No. 2


The only exception to this dial peer concept is when both POTS dial peers are connected to the same concentrator, as shown in Figure 88. In this circumstance, because both dial peers share the same destination IP address, you need not configure a VoATM dial peer.


Figure88: Communication Between Dial Peers Sharing the Same Concentrator


When configuring dial peers, you need to understand the relationship between the destination pattern and the session target. The destination pattern represents the pattern for the device at the voice connection endpoint, such as a telephone or a PBX. The session target represents the serial port on the peer Cisco MC3810 at the other end of the ATM connection. Figure 89 and Figure 90 show the relationship between the destination pattern and the session target, as seen from the perspective of both Cisco MC3810 concentrators in a VoATM configuration.


Figure89: Relationship Between the Destination Pattern and Session Target from the Perspective of Cisco MC3810 No.1



Figure90:
Relationship Between the Destination Pattern and Session Target from the Perspective of Cisco MC3810 No.2


Configuring POTS Dial Peers

To configure a POTS dial peer, you need to uniquely identify the peer (by assigning it a unique tag number), define its telephone number, and associate it with a voice port through which calls will be established. Under most circumstances, the default values for the remaining dial-peer configuration commands will be sufficient to establish connections.

To configure POTS peers, use the following commands beginning in global configuration mode:

Command Purpose

Step1

Router(config)# dial-peer voice number pots

Defines a POTS dial peer and enters dial-peer configuration mode. All subsequent commands that you enter in dial-peer configuration mode before you exit will apply to this dial peer.

The number tag identifies the dial peer and must be unique on the router. Do not duplicate a specific number tag.

Step2

Router(config-dial-peer)# destination-pattern string

Configures the dial peer destination pattern.

The string argument is a series of digits that specify the E.164 or private dialing plan telephone number. Valid entries are the digits 0-9 and the letters A-D. The following special characters can be entered in the string:

  • The star character (*) and the pound sign (#) that appear on standard touch-tone dial pads can be used in any dial string. However, these characters cannot be used as leading characters in a string (for example, *650).

  • The period (.) can be entered any time, and is used as a wildcard character.

  • The comma (,) can be used only in prefixes, and is used to insert a 1-second pause or a delay.

  • The timer (T) character can be used to configure variable-length dial plans. For more information, see the "Dial Planning and Dial-Peer Digit Manipulation Options" section in the "Configuring Voice over Frame Relay" chapter.

Step3

Router(config-dial-peer)# port slot/port

Associates this POTS dial peer with a specific logical dial interface. Enter the slot/port number of the voice port connected to the POTS dial peer.

Step4

Router(config-dial-peer)# preference value

(Optional) Configures a preference for the POTS dial peer. The value is a number from 0-10 where the lower the number, the higher the preference. If POTS and voice-network (VoATM) peers are mixed in the same hunt group, POTS dial peers will be searched first, even if a voice-network peer has a higher preference number.

For more information about hunt groups and preferences, see the "Dial Planning and Dial-Peer Digit Manipulation Options" section in the "Configuring Voice over Frame Relay" chapter.

Step5

Router(config-dial-peer)# forward-digits {num-digit 
| all}

(Optional) If you will use the digit-forwarding feature, configures the digit-forwarding method that will be used on the dial peer.

Step6

Router(config-dial-peer)# prefix string

(Optional) If the forward digits feature was not configured in the last step, assigns the dialed digits prefix for the dial peer.

To configure additional POTS dial peers, exit dial-peer configuration mode by entering the exit command, and repeat the previous steps.

Configuring VoATM Dial Peers

To configure a VoATM dial peer, you need to uniquely identify the peer (by assigning it a unique tag number), and to define the outgoing serial port number and the virtual circuit number.

To configure VoATM dial peers, use the following commands beginning in global configuration mode:

Command Purpose

Step1

Router(config)# dial-peer voice tag voatm

Defines a VoATM dial peer for VoATM and enters dial-peer configuration mode.

The tag value identifies the dial peer and must be unique on the router. Do not duplicate a specific tag number.

Step2

Router(config-dial-peer)# destination-pattern string

Configures the dial peer destination pattern. The same restrictions for the string listed in the POTS dial-peer configuration also apply to the VoATM destination pattern.

Step3

Router(config-dial-peer)# session target ATM0 {svc 
nsap address | pvc [vpi/vci | name]}

Configures the ATM session target for the dial peer. Specify ATM0 as the interface.

When you use SVCs, the system reconciles dialed digits with the remote ATM interface voice NSAP address.


NoteIf you are using PVCs for voice, you can specify a PVC defined on the ATM interface as a session target, by using a name or a VPI/VCI combination.

Step4

Router(config-dial-peer)# codec type [bytes 
payload_size]

Specifies the voice coder rate of speech and payload size for the dial peer. The default dial peer codec is g729r8. Note that the CiscoMC3810 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 (?).


NoteIf configuring regular switched voice calls on the CiscoMC3810, you must configure the codec type on the voice port.

Step5

Router(config-dial-peer)# fax rate 4800

(Fax only, optional) I Configures the fax rate on the dial peer.

If you are configuring a dial peer for faxes over ATM SVCs, the default codec setting for the voice port does not function properly unless the fax rate is slowed from the typical speed of 9600 bps. Therefore, you can either change the codec (see Step 4) or change the fax rate to 4800 bps or 2400 bps.

Step6

Router(config-dial-peer)# no vad

(Optional) Disables VAD on the dial peer. This command is enabled by default.

Step7

Router(config-dial-peer)# preference value

(Optional) Configures a preference for the VoATM dial peer. The value is a number from 0-10 where the lower the number, the higher the preference.

Step8

Router(config-dial-peer)# alt-dial string

(Optional) Configures the alternate dial-out string when configuring on-net-to-off-net alternative dialing.


NoteThe Cisco MC3810 supports ATM traffic over T1/E1 controller 0 only.

To configure additional VoATM dial peers, exit dial-peer configuration mode by entering the exit command, and repeat the previous steps.

Depending on your configuration, you may need to consider how to configure your voice networks with excess digit playout, forward digits and default voice routes, or to use hunt groups with dial-peer preferences. For more information on these topics, see the "Dial Planning and Dial-Peer Digit Manipulation" section in the "Configuring Voice over Frame Relay" chapter. Although the descriptions for these topics use VoFR examples, these topics also apply to VoATM.

Configuring VoATM Dial Peers for Cisco-Trunk (Private Line) Calls

If you will be sending Cisco-trunk (private line) calls over ATM, you must configure the VoATM dial peers to specifically support Cisco-trunk (private line) calls. Cisco-trunk (private line) calls are permanent calls.


NoteYou can also create a voice class to configure trunk conditioning values for the idle and out-of-service (OOS) states, and then assign the voice class to the VoATM dial peer. For more information, see the "Configuring Voice-Related Support Features" chapter.

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

Command Purpose

Step1

Router(config)# dial-peer voice number voatm

Defines a VoATM dial peer and enters dial-peer configuration mode.

The number tag identifies the dial peer and must be unique on the router. Do not duplicate a specific number tag.

Step2

Router(config-dial-peer)# destination-pattern string

Configures the dial peer destination pattern.

Step3

Router(config-dial-peer)# session target interface 

Configures the VoATM session target for the dial peer.

Step4

Router(config-dial-peer)# session protocol 
cisco-switched 

Configures the session protocol to support Cisco-trunk calls.

The cisco-switched option is the default setting, and entering this command is not required.

Step5

Router(config-dial-peer)# codec type [bytes bytes]

Specifies 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 (?).


NoteOn 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 (the cisco-trunk keyword), you must configure the codec type on the dial peer. You cannot specify the payload size on the voice port.

Step6

Router(config-dial-peer)# dtmf-relay

(Optional) If the codec type is a low bit-rate codec such as g729 or g723, specifies 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.

Step7

Router(config-dial-peer)# signal-type {cas | cept | 
ext-signal | transparent}

Defines the flavor of the ABCD signalling packets that are generated by the voice port and sent to the data network. The signal type must be configured to the same setting at both ends of the permanent voice call.

Enter cas to support CAS. Enter cept to support the European CEPT standard (related to MEL CAS).

Enter ext-signal to indicate that ABCD signalling packets should not be sent, for configurations where the line signalling information is carried externally to the voice port.

Enter transparent (for digital T1/E1 interfaces on the Cisco MC3810 only) to read the ABCD signalling 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 signalling).

Step8

Router(config-dial-peer)# no vad

(Optional) Disables VAD on the dial peer. This command is enabled by default.

Step9

Router(config-dial-peer)# sequence-numbers 

(Optional) Enables the voice sequence number if required for your configuration. This command is disabled by default.

Step10

Router(config-dial-peer)# preference value

(Optional) Configures a preference for the VoATM dial peer. The value is a number from 0-10 where the lower the number, the higher the preference in hunt groups.

Step11

Router(config-dial-peer)# fax rate {2400 | 4800 | 
7200 | 9600 | 14400 | disable | voice}

(Optional) Configures 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.

To configure another VoATM dial peer for Cisco-trunk (private line) calls, exit dial-peer configuration mode and repeat Steps 1 through 11.

To configure Cisco-trunk permanent calls on a Cisco MC3810, see the next section, "Configuring Cisco-Trunk Permanent Calls on a Cisco MC3810."

Configuring Cisco-Trunk Permanent Calls on a Cisco MC3810

A Cisco-trunk (private line) call is basically a normal dynamic switched call of indefinite duration that uses a fixed destination telephone number and includes optional transparent end-to-end signalling. The telephone number of the destination endpoint is permanently configured into the router so that it always selects a fixed destination. After the call is established, either at boot-up or when configured, the call stays up until one of the voice ports or network ports is shut down, or until a network disruption occurs.

The connection trunk voice-port configuration command is used to establish a Cisco-trunk call; the dial peer is configured using the session protocol cisco-switched command, which invokes the Cisco proprietary session protocol.

The Cisco-trunk (private line) trunk call functionality provides the following benefits:

To configure Cisco-trunk permanent calls on a Cisco MC3810 for VoATM, use the following commands beginning in interface configuration mode:

Command Purpose

Step1

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

Enters voice-port configuration mode.

Step2

Router(config-voiceport)# connection trunk 
destination-string [answer-mode]

Configures the trunk connection, specifying the telephone number in the destination-string argument.

When you configure 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 port operates in master mode. Enter the answer-mode keyword to specify that the voice port should operate in slave mode.

Step3

Router(config-voiceport)# shutdown

Shuts down the voice port.

Step4

Router(config-voiceport)# no shutdown

Reactivates the voice port to enable the trunk connection to take effect.


NoteEvery 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.

Disabling Dial-Peer Hunting on a Dial Peer

To disable dial-peer hunting on a dial peer, enter the following commands beginning in global configuration mode:

Command Purpose

Step1

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

Enters dial-peer configuration mode for the specified dial peer.

Step2

Router(config-dial-peer)# huntstop

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

To reenable dial-peer hunting on a dial peer, enter the fsollowing commands beginning in global configuration mode:

Command Purpose

Step1

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

Enters dial-peer configuration mode for the specified dial peer.

Step2

Router(config-dial-peer)# no huntstop

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

Verifying the VoATM Connection

Verify that the voice connection is working by doing the following:

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

Troubleshooting Tips

If you are having trouble connecting a call and you suspect the problem is associated with the dial-peer configuration, you can try to resolve the problem by performing the following tasks:

VoATM Configuration Examples

Configuration examples for VoATM are shown in the following sections:

Back-to-Back VoATM PVCs Example

Figure 91 shows a configuration example for two Cisco MC3810 concentrators configured back-to-back, with VoATM configured for both concentrators. This setup is useful to test your VoATM configuration locally to ensure voice connections can be made locally before you configure VoATM across a larger network. Following the figure are the commands required to configure the Cisco MC3810 concentrators in this example.


NoteThere may be special considerations for configuring back-to-back ATM compared to configuring for an ATM network.


Figure91: Back-to-Back VoATM PVCs Configuration


Cisco MC3810 No. 1 Cisco MC3810 No. 2
hostname location1
no ip domain-lookup
!
interface Ethernet0
 ip address 10.1.10.1 255.255.255.0
 no ip mroute-cache
 no ip route-cache
!
hostname location2
no ip domain-lookup
!
interface Ethernet0
 ip address 10.1.20.1 255.255.255.0
 no ip mroute-cache
 no ip route-cache
!
controller T1 0
 clock source internal
 mode atm
!
interface atm0 point-to-point
ip address 10.1.1.1 255.255.255.0
 no ip mroute-cache
!
controller T1 0
clock source line
mode atm
!
interface atm0 point-to-point
ip address 10.1.1.2 255.255.255.0
 no ip mroute-cache
!
pvc 1 1 100
 encapsulation aal5mux voice
 vbr-rt 384 192 48
!
pvc 2 1 200
 encapsulation aal5snap
 map-group atm1
!
router rip
 redistribute connected
 network 10.0.0.0
!
no ip classless
!
pvc 1 1 100
 encapsulation aal5mux voice
 vbr-rt 384 192 48
!
pvc 2 1 200
 encapsulation aal5snap
 map-group atm1
!
router rip
redistribute connected
network 10.0.0.0
!
no ip classless
!
map-list atm1
 ip 10.1.1.2 atm pvc 2 broadcast
!
dial-peer voice 1 pots
 destination-pattern 10
 port 1/1
!
dial-peer voice 202 voatm
 destination-pattern 2.
 session target ATM0 1
!
end
map-list atm1
 ip 10.1.1.1 atm pvc 2 broadcast
!
dial-peer voice 1 pots
 destination-pattern 20
 port 1/1
!
dial-peer voice 202 voatm
 destination-pattern 1.
 session target ATM0 1
!
end

Voice and Data Traffic over ATM PVCs Example

Figure 92 shows an example for both voice and data traffic over ATM between two CiscoMC3810 concentrators, including configuration for voice ports and dial peers. Following the figure are the commands required to configure the Cisco MC3810 concentrators in this example.


Figure92: Voice and Data Traffic over ATM PVCs Configuration Example


Cisco MC3810 No. 1 Cisco MC3810 No. 2
interface Ethernet0
 ip address 172.22.124.239 255.255.0.0
!
controller T1 0
 mode ATM
!
interface atm0 point-to-point
 ip address 223.223.224.229 255.255.255.0
 no ip mroute-cache
 no ip route-cache
 map-group atm1
!
interface Ethernet0
 ip address 172.22.124.247 255.255.0.0
!
controller T1 0
 mode ATM
!
interface atm0 point-to-point
 ip address 223.223.224.228 255.255.255.0
 no ip mroute-cache
 no ip route-cache
 map-group atm1
!
pvc 26 26 200
 encapsulation aal5snap
!
pvc 27 27 270
 encapsulation aal5mux voice
 vbr-rt 384 192 48
!
no ip classless
!
pvc 26 26 200
 encapsulation aal5snap
!
pvc 27 27 270
 encapsulation aal5mux voice
 vbr-rt 384 192 48
!
no ip classless
!
map-list atm1
 ip 223.223.224.228 atm pvc 26 broadcast
!
voice-port 1/1
!
voice-port 1/2
!
voice-port 1/3
!
voice-port 1/4
!
map-list atm1
 ip 223.223.224.229 atm pvc 26 broadcast
!
login
line vty 1 4
 login
!
voice-port 1/1
!
voice-port 1/2
!
voice-port 1/3
!
voice-port 1/4
!
dial-peer voice 1 pots
 destination-pattern 3488801
 port 1/1
!
dial-peer voice 2 pots
 destination-pattern 3488802
 port 1/2
!
end
dial-peer voice 1 pots
 destination-pattern 3388801
 port 1/1
!
dial-peer voice 2 pots
 destination-pattern 3388802
 port 1/2
!
dial-peer voice 1001 voatm
 destination-pattern 348....
 session target ATM0 27 
!
end

VoATM SVCs Example

Figure 93 shows the configurations of two Cisco MC3810 multiservice access concentrators that each have voice dial peers connecting over ATM SVCs.


Figure93: Sample Configuration: Two Cisco MC3810s Using ATM SVCs for Voice


Cisco MC3810 No. 1 Cisco MC3810 No. 2
hostname MC3810A
!
network-clock base-rate 64k
ip subnet-zero
ip wccp version 2
ip host keyer-ultra 223.255.254.254
!
appletalk routing
ipx routing 1111.0045.0005
hostname MC3810B
!
network-clock base-rate 64k
ip subnet-zero
ip wccp version 2
ip host keyer-ultra 223.255.254.254
!
appletalk routing
ipx routing 1111.0045.0002
controller T1 0
 framing esf
 linecode b8zs
 mode atm
controller T1 0
 framing esf
 linecode b8zs
 mode atm
controller T1 1
 framing esf
 clock source internal
 linecode b8zs
 mode cas
 voice-group 1 timeslots 1-24 type e&m-immediate-start
controller T1 1
 framing esf
 clock source internal
 linecode b8zs
 mode cas
 voice-group 1 timeslots 1-24 type e&m-immediate-start
interface atm0
 ip address 9.1.1.5 255.0.0.0
 no ip directed-broadcast
 no ip route-cache
 atm pvc 1 0 5 qsaal
 atm pvc 2 0 16 ilmi
 atm ilmi-keepalive
 atm voice aesa default
interface atm0
 ip address 9.1.1.6 255.0.0.0
 no ip directed-broadcast
 no ip route-cache
 atm pvc 1 0 5 qsaal
 atm pvc 2 0 16 ilmi
 atm ilmi-keepalive
 atm voice aesa default
voice-port 1/1
 !
voice-port 1/2
 !
voice-port 1/3
 timeouts call-disconnect 0
!
.
.
voice-port 1/24
voice-port 1/1
 !
voice-port 1/2
 !
voice-port 1/3
!
.
.
.
voice-port 1/24
.
.
.
dial-peer voice 2 pots
 destination-pattern 5558802
 port 1/2
!
dial-peer voice 3 pots
 destination-pattern 5558803
 port 1/3
!
dial-peer voice 4 pots
 destination-pattern 5558804
 port 1/4
!
dial-peer voice 5 pots
destination-pattern 5558805
 port 1/5
.
.
.
dial-peer voice 102 voatm
 destination-pattern 5559...
 session target ATM0 svc nsap 47.0091810000000002F26D4901.00107B09C645.FE
.
.
.
dial-peer voice 2 pots
 destination-pattern 5559802
 port 1/2
!
dial-peer voice 3 pots
 destination-pattern 5559803
 port 1/3
!
dial-peer voice 4 pots
 destination-pattern 5559804
 port 1/4
!
dial-peer voice 5 pots
 destination-pattern 5559805
 port 1/5
.
.
.
dial-peer voice 202 voatm
 destination-pattern 5558...
 session target ATM0 svc nsap 47.0091810000000002F26D4901.00107B4832E1.FE


hometocprevnextglossaryfeedbacksearchhelp
Posted: Thu Jul 27 00:20:51 PDT 2000
Copyright 1989-2000©Cisco Systems Inc.