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Configuring Cisco MC3810 Series Concentrators to Use High-Performance Compression Modules

Configuring Cisco MC3810 Series Concentrators to Use High-Performance Compression Modules

This document describes feature changes introduced in Cisco IOS Release 12.0(7)XK and supported in Cisco IOS Release 12.1(2)T and later for Cisco MC3810 series concentrators that contain high-performance voice compression modules (HCMs).

This document includes the following sections:

Feature Overview

High-performance voice compression modules (HCMs) provide voice compression according to the voice compression coding algorithm (codec) specified when the Cisco MC3810 is configured. Table 1 shows the number of voice channels each type of compression module can support.


Table 1: Voice Compression Module Application Information
Type Codec Packaging Complexity (see Table 2) Voice Channels per HCM

HCM2

High complexity (codec complexity set to high)

4

Medium complexity (codec complexity set to medium)

8

HCM6

High complexity (codec complexity set to high)

12

Medium complexity (codec complexity set to medium)

24


Table 2: Codec Packaging Information
Codec Packaging Codecs

High complexity

G.711ulaw, G.711alaw
G.723.1(r5.3), G.723.1 Annex A(r5.3), G.723.1(r6.3), G.723.1 Annex A(r6.3)
G.726(r16), G.726(r24), G.726(r32)
G.728
G.729, G.729 Annex B
fax relay

Medium complexity

G.711ulaw, G.711alaw
G.726(r16), G.726(r24), G.726(r32)
G.729 Annex A, G.729 Annex B with Annex A
fax relay

Benefits

HCMs support more voice channels than the earlier voice compression modules (VCMs) used in the Cisco MC3810 series.

Restrictions

The following restrictions apply to HCMs:

Related Features and Technologies

Voice over Internet Protocol (VoIP)

Voice over Frame Relay (VoFR)

Voice over Asynchronous Transfer Mode (VoATM)

Related Documents

Supported Platforms

Supported Standards, MIBs, and RFCs

RFCs

MIBs

International Telecommunication Union (ITU-T) G-Series Codec Compression Specifications

Prerequisites

One or two HCM modules must be installed in your Cisco MC3810 chassis.

Note An HCM may not be combined with a VCM in one chassis.

Configuration Tasks

Complete the following tasks to configure the Cisco MC3810 voice ports for operation with one or two HCMs installed:

Configuring Codec Complexity

To configure codec complexity for voice ports, enter the following commands, beginning in privileged EXEC mode. Commands apply to both analog and digital voice ports unless otherwise indicated. You enter the codec complexity command in voice-card configuration mode. On the Cisco MC3810 series, voice-card 0 is used as a virtual voice-card, and the setting applies to all voice ports on a Cisco MC3810.

This procedure does not cover other voice-port configuration commands that may be required. To learn more, see the Cisco IOS Multiservice Applications Configuration Guide and the Cisco IOS Multiservice Applications Command Reference for Cisco IOS Release 12.1.

Command Purpose

Step 1 

router# show voice dsp

Check the DSP voice channel activity. If any DSP voice channels are in the busy state, you cannot change the codec complexity.

When all of the DSP channels are in the idle state, continue to step 2.

Step 2 

router# configure terminal

Enter global configuration mode.

Step 3 

router(config)# voice-card 0

Enter voice-card configuration mode and specify voice card 0. Voice card 0 provides the configuration mode for setting the codec complexity on a Cisco MC3810.

Step 4 

router(config-voicecard)# codec
complexity {high | medium}

Specify the codec complexity for this Cisco MC3810 according to the bandwidth requirements and the number of voice channels to be supported per DSP. The default is medium complexity, which provides four voice channels per DSP.

See the "codec complexity" section in the Command Reference for information about the codec complexity command.

Step 5 

router(config-voicecard)# exit

Exit from voice-card configuration mode.

Verifying Codec Complexity Settings

To verify the codec complexity configuration, enter the show running-config command to display the current voice-card setting. If medium complexity is specified, the codec complexity setting is not displayed. If high complexity is specified, the setting codec complexity high is displayed. The following example shows an excerpt from the command output if high complexity has been specified:

Router# show running-config
.
.
.
hostname router-alpha 
 
voice-card 0
 codec complexity high 
.
.

Specifying Codecs for Network Dial Peers

Follow these steps to specify a codec for each network dial peer according to the codec complexity setting selected for this Cisco MC3810. If you do not set codec complexity and specify a codec, the defaults remain in effect: medium complexity and G.729, 8000 bps.

This does not cover the complete dial-peer configuration procedure. To learn more, see the Cisco IOS Multiservice Applications Configuration Guide and the Cisco IOS Multiservice Applications Command Reference for Cisco IOS Release 12.1.

Command Purpose

Step 1 

Router# configure terminal

Enter global configuration mode.

Step 2 

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

Enter dial-peer configuration mode and specify a network dial peer for which to specify a codec.

tag is one or more digits to identify the dial peer. Valid entries are 1 to 2147483647.

Step 3 

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

Specify a codec for the dial peer. Codec types are as follows:

g711alaw, g711ulaw,
g723ar53, g723ar63, g723r53, g723r63, g726r16, g726r24, g726r32,
g728,
g729abr8, g729ar8, g729br8, g729r8

The default is g729r8.

Optionally specify the voice payload (in bytes) of each frame.

For information about the options available for the codec command, see the command reference section or enter ?.

Step 4 

Router(config-dial-peer)# exit

Exit from dial-peer configuration mode.

Verifying Network Dial Peers

Follow the procedure below to verify dial-peer configuration. To learn more about these commands, see the Cisco IOS Multiservice Applications Configuration Guide and the Cisco IOS Multiservice Applications Command Reference for Cisco IOS Release 12.1.

Enter the privileged EXEC show dial-peer voice command. The following text is sample output from the show dial-peer voice command for a VoIP dial peer:

Router# show dial-peer voice 10
VoiceOverIpPeer10
        information type = voice,
        tag = 10, destination-pattern = \Q555....',
        answer-address = \Q', preference=0,
        group = 10, Admin state is up, Operation state is up,
        incoming called-number = \Q', connections/maximum = 0/unlimited,
        DTMF Relay = disabled,
        application associated: 
        type = voip, session-target = \Qipv4:10.1.1.1',
        technology prefix: 
        ip precedence = 0, UDP checksum = disabled,
        session-protocol = cisco, req-qos = best-effort, 
        acc-qos = best-effort, 
        fax-rate = voice,   payload size =  20 bytes
        codec = g711alaw,   payload size =  160 bytes,
        Expect factor = 10, Icpif = 30,signaling-type = cas,
        VAD = enabled, Poor QOV Trap = disabled,
        voice class perm tag = \Q'
        Connect Time = 0, Charged Units = 0,
        Successful Calls = 0, Failed Calls = 0,
        Accepted Calls = 0, Refused Calls = 0,
        Last Disconnect Cause is "",
        Last Disconnect Text is "",
        Last Setup Time = 0.

The following text is sample output from the show dial-peer voice command for a VoFR dial peer:

Router# show dial-peer voice 20
VoiceOverFRPeer20
        information type = voice,
        tag = 20, destination-pattern = \Q555....',
        answer-address = \Q', preference=0,
        group = 20, Admin state is up, Operation state is up,
        incoming called-number = \Q', connections/maximum = 0/unlimited,
        DTMF Relay = disabled,
        application associated: 
        type = vofr, session-target = \QSerial0 120',
        called number = \Q',
        session-protocol = cisco-switched, 
        fax-rate = voice,   payload size =  30 bytes
        codec = g729r8,   payload size =  30 bytes,
        signaling-type = cas,
        VAD = enabled,
        Voice Sequence Numbers = disabled,
        voice class perm tag = \Q'
        Connect Time = 0, Charged Units = 0,
        Successful Calls = 0, Failed Calls = 0,
        Accepted Calls = 0, Refused Calls = 0,
        Last Disconnect Cause is "",
        Last Disconnect Text is "",
        Last Setup Time = 0.

The following text is sample output from the show dial-peer voice command for a VoATM dial peer:

Router# show dial-peer voice 1
VoiceOverATMPeer1
        information type = voice,
        tag = 1, destination-pattern = \Q555....',
        answer-address = \Q', preference=5,
        group = 1, Admin state is up, Operation state is up,
        incoming called-number = \Q', connections/maximum = 0/unlimited,
        DTMF Relay = disabled,
        application associated: 
        type = voatm, session-target = \QATM0 pvc 101/1001',
        session-protocol = cisco-switched, 
        fax-rate = voice,   payload size =  30 bytes
        codec = g729r8,   payload size =  30 bytes,
        signaling-type = cas,
        VAD = enabled,
        Voice Sequence Numbers = disabled,
        voice class perm tag = \Q'
        Connect Time = 0, Charged Units = 0,
        Successful Calls = 0, Failed Calls = 0,
        Accepted Calls = 0, Refused Calls = 0,
        Last Disconnect Cause is "",
        Last Disconnect Text is "",
        Last Setup Time = 0.

Command Reference

This section documents new or modified commands. Modified commands are indicated by an
asterisk (*). All other commands used with this feature are documented in the Cisco IOS Release 12.1 command reference publications.

codec (dial-peer)

To specify the voice codec for a network dial peer, enter the codec dial-peer configuration command. Use the no form of this command to restore the default value.

codec codec [bytes payload-size]

no codec

Syntax Description

codec

Codec options on Cisco MC3810 series equipped with HCM, and with codec complexity set to high or medium:

  • g711alaw---G.711 A Law, 64000 bps

  • g711ulaw---G.711 u Law, 64000 bps

  • g723ar53---G.723.1 Annex A, 5300 bps

  • g723ar63---G.723.1 Annex A, 6300 bps

  • g723r53---G.723.1, 5300 bps

  • g723r63---G.723.1, 6300 bps

  • g726r16---G.726, 16000 bps

  • g726r24---G.726, 24000 bps

  • g726r32---G.726, 32000 bps

  • g728---G.728, 16000 bps

  • g729abr8---G.729 Annex A and Annex B, 8000 bps

  • g729ar8---G.729 Annex A, 8000 bps

  • g729br8---G.729 Annex B, 8000 bps

  • g729r8---G.729, 8000 bps

bytes

(Optional) The voice payload for each frame.

payload-size

(Optional) Number of bytes you specify as the voice payload of each frame. Values depend on the codec type and the packet voice protocol. See Table 3 for valid entries and default values.

Defaults

If no codec is specified, dial peers are configured for g729r8 and the voice payload is as shown in Table 3 for G.729r8.

If a codec is specified without the bytes keyword, the voice payload is as shown in Table 3.

Command Modes

Dial-peer configuration

Command History

Release Modification

11.3(1)T

This command was introduced as a Cisco 3600 series VoIP dial-peer configuration command.

12.0(4)T

This command was modified for VoFR dial peers. On the Cisco MC3810 series, this command was first supported as a dial-peer command.

12.0(5)XK

The g729br8 codec and pre-ietf keyword were added for the Cisco 2600 and 3600 series.

12.0(7)T

This command was implemented in the 12.0(7)T release.

12.0(7)XK

The g729abr8 and g729ar8 codecs were added for the Cisco MC3810 series and the keyword pre-ietf was deleted.

12.1(2)T

This command was implemented in the 12.1(2)T release.

Usage Guidelines

A codec type can be configured on the dial-peer if it is supported under the codec complexity setting you have specified.

The dial-peer configuration command is particularly useful when you must change to a small-bandwidth codec. Large-bandwidth codecs, such as G.711, do not fit in a small-bandwidth link. However, g711alaw and g711ulaw provide higher-quality voice transmission than other codecs. For almost toll quality (and a significant savings in bandwidth), g729r8 provides near-toll quality with considerable bandwidth savings.

If the destination router does not support a codec required by the originating router, the call setup fails.

You can change the payload of each voice packet frame by using the bytes payload-size setting. However, increasing the payload size can add processing delay for each voice packet. Table 3 describes the voice payload options and default values for the codecs and packet voice protocols.


Table 3: Voice Payload-per-Frame Options and Defaults
Codec Protocol Voice Payload Options (bytes) Default Voice Payload (bytes)
g711alaw
g711ulaw

VoIP
VoFR
VoATM

80, 160
40 to 240 in multiples of 40
40 to 240 in multiples of 40

160
240
240

g723ar53
g723r53

VoIP
VoFR
VoATM

20 to 220 in multiples of 20
20 to 240 in multiples of 20
20 to 240 in multiples of 20

20
20
20

g723ar63
g723r63

VoIP
VoFR
VoATM

24 to 216 in multiples of 24
24 to 240 in multiples of 24
24 to 240 in multiples of 24

24
24
24

g726r16

VoIP
VoFR
VoATM

20 to 220 in multiples of 20
10 to 240 in multiples of 10
10 to 240 in multiples of 10

40
60
60

g726r24

VoIP
VoFR
VoATM

30 to 210 in multiples of 30
15 to 240 in multiples of 15
30 to 240 in multiples of 15

60
90
90

g726r32

VoIP
VoFR
VoATM

40 to 200 in multiples of 40
20 to 240 in multiples of 20
40 to 240 in multiples of 20

80
120
120

g728

VoIP
VoFR
VoATM

10 to 230 in multiples of 10
10 to 240 in multiples of 10
10 to 240 in multiples of 10

40
60
60

g729abr8
g729ar8
g729br8
g729r8

VoIP
VoFR
VoATM

10 to 230 in multiples of 10
10 to 240 in multiples of 10
10 to 240 in multiples of 10

20
30
30

Examples

The following example configures VoIP dial peer number 10 to use codec type g723r53 (G.723.1 at 5300 bps), and specifies a non-default voice payload size of 40 bytes:

router(config)# dial-peer voice 10 voip
router(config-dialpeer)# codec g723r53 bytes 40

Related Commands

Command Description

codec complexity

This voice-card configuration command sets codec complexity and call density.

show dial-peer voice

Displays the codec setting for dial peers.

codec complexity

To match the DSP complexity packaging to the codec(s) to be supported, enter the codec complexity voice-card configuration command. The no form of the command restores the default value.

codec complexity {high | medium}

no codec complexity

Syntax Description

high

With high complexity packaging, each DSP supports two voice channels encoded in any of the following formats: G.711ulaw, G.711alaw, G.723.1(r5.3), G.723.1 Annex A(r5.3), G.723.1(r6.3), G.723.1 Annex A(r6.3), G.726(r16), G.726(r24), G.726(r32), G.729, G.729 Annex B, G.728, and fax relay.

medium

With medium complexity packaging, each DSP supports four voice channels encoded in any of the following formats: G.711ulaw, G.711alaw, G.726(r16), G.726(r24), G.726(r32), G.729 Annex A, G.729 Annex B with Annex A, and fax relay. This is the default.

Defaults

The DSP supports medium complexity codecs.

Command Modes

Voice-card configuration

Command History

Release Modification

12.0(5)XK

The command was introduced for the Cisco 2600 and 3600 series.

12.0(7)T

This command was implemented in the 12.0(7)T release.

12.0(7)XK

This command was first supported on the Cisco MC3810 series for use with the high performance compression module (HCM).

12.1(2)T

This command was implemented in the 12.1(2)T release.

Usage Guidelines

Select a higher codec complexity if that is required in order to support a particular codec or combination of codecs.

Select a lower codec complexity to support the greatest number of voice channels, provided that the lower complexity is compatible with the particular codecs in use.

To change codec complexity, all of the DSP voice channels must be in the idle state.

Codec complexity refers to the amount of processing required to perform voice compression. Codec complexity affects the call density---the number of calls that can take place on the digital signal processors (DSPs). With higher codec complexity, fewer calls can be handled.

Note In the Cisco MC3810 series, this command is valid only with HCM(s) installed, and you must specify voice card 0 in the command mode. If two HCMs are installed, the codec complexity command configures both HCMs at once.

Examples

The following example sets the codec complexity to high on a Cisco MC3810 containing one or two HCMs:

router(config)# voice-card 0
router(config-voicecard)# codec complexity high

The following example sets the codec complexity to high on voice card 1 in a Cisco 2600 or 3600 series router:

router(config)# voice-card 1
router(config-voicecard)# codec complexity high

Related Commands

Command Description

show voice dsp

Shows the current status of all DSP voice channels.

ds0-group

To specify the DS0 timeslots that make up a logical voice port on a T1 or E1 controller, and to specify the signaling type, enter the ds0-group controller configuration command. Use the no form of the command to remove the DS0 group and signaling setting.

ds0-group ds0-group-number timeslots timeslot-list type signal-type

no ds0-group ds0-group-number

Syntax Description

ds0-group-number

A number from 0 to 23 (for T1) or from 0 to 30 (for E1) to identify the DS0 group.

timeslot-list

A single timeslot number, a range of numbers, or multiple ranges of numbers separated by commas. Allowable values are 1 to 24 for T1 and 1 to 32 for E1. Examples are:

  • 2

  • 1-15, 17-23

  • 1-23

  • 2, 4, 6-12, 27-32

type

The signaling method selection for type depends on the connection that you are making. The E&M interface allows connection for PBX trunk lines (tie lines) and telephone equipment. The FXS interface allows connection of basic telephone equipment and PBXs. The FXO interface is for connecting the central office (CO) to a standard PBX interface where permitted by local regulations; it is often used for off-premises extensions.

The following options are available on T1 and E1 controllers:

  • e&m-immediate-start---no specific off-hook and on-hook signaling

  • e&m-delay-dial---the originating endpoint sends an off-hook signal and then waits for an off-hook signal followed by an on-hook signal from the destination

  • e&m-wink-start---the originating endpoint sends an off-hook signal and waits for a wink signal from the destination

  • fxs-ground-start---Foreign Exchange Station ground-start signaling support

  • fxs-loop-start ---Foreign Exchange Station loop-start signaling support

  • fxo-ground-start---Foreign Exchange Office ground-start signaling support

  • fxo-loop-start---Foreign Exchange Office loop-start signaling support

The following options are available only on E1 controllers on the Cisco MC3810 series:

  • e&m-melcas-immed---E&M Mercury Exchange Limited Channel Associated Signaling (MELCAS) immediate start signaling support

  • e&m-melcas-wink---E&M MELCAS wink start signaling support

  • e&m-melcas-delay---E&M MELCAS delay start signaling support

  • fxo-melcas---MELCAS Foreign Exchange Office signaling support

  • fxs-melcas---MELCAS Foreign Exchange Station signaling support

The following options are available only when the mode ccs command is enabled on the Cisco MC3810 series for transparent CCS support:

  • ext-sig-master---For the specified channel(s), automatically generates the off-hook signal and stays in the off-hook state

  • ext-sig-slave---For the specified channel(s), automatically generates the answer signal when a call is terminated to that channel

Defaults

No DS0 group is defined.

Command Modes

Controller configuration

Command History

Release Modification

11.2

This command was introduced on the Cisco AS5300 as cas-group.

12.0(1)T

The cas-group command was first supported on the Cisco 3600 series.

12.0(5)T

This command was renamed ds0-group on the Cisco AS5300 and on the Cisco 2600 and 3600 series (requires Digital T1 Packet Voice Trunk Network Modules).

12.0(7)XK

Support for this command was extended to the Cisco MC3810 series. When the ds0-group command became available on the Cisco MC3810 series, the voice-group command was removed and no longer supported.

12.1(2)T

This command was implemented in the 12.1(2)T release.

Usage Guidelines

The ds0-group command automatically creates a logical voice port that is numbered as follows on the Cisco MC3810 series: slot:ds0-group-number.

On the Cisco MC3810 series, the slot number is the controller number. Although only one voice port is created for each DS0 group, applicable calls are routed to any channel in the group.

On the Cisco MC3810 series when configured for transparent CCS, the channel type configured as the ext-sig-master is considered the master side of the permanent virtual circuit (PVC) connection which is responsible for establishing the PVC connection. After the master channel is configured, a fixed timer of 30 seconds starts. The voice-signaling driver then generates an off-hook signal on the master voice channel after the timer expires. The call is treated as a regular call, and the master channel does not hang up after the connection is made. If the call does not go through, or if the T1/E1 trunk is down, the 30-second timer on the master channel side restarts. A new off-hook signal is then generated at the master channel side after the timer expires.

Examples

The following example configures DS0 groups 0 and 1 with different CAS signaling on controller T1 0:

router(config)# controller T1 0
router(config-controller)# mode cas
router(config-controller)# framing esf
router(config-controller)# linecode b8zs
router(config-controller)# ds0-group 0 timeslot 1-10 type fxs-ground-start
router(config-controller)# ds0-group 1 timeslot 11-24 type fxo-loop-start

The following example configures DS0 groups 1 and 2 on controller T1 0 to support transparent CCS:

router(config)# controller T1 0
router(config-controller)# mode ccs cross-connect
router(config-controller)# ds0-group 1 timeslot 1-10 type ext-sig-master
router(config-controller)# ds0-group 2 timeslot 11-24 type ext-sig-slave

Related Commands

Command Description

codec complexity

Matches the DSP complexity packaging to the codec(s) to be supported. Voice channels in DS0 groups must be in the idle state before codec complexity can be changed.

mode ccs

Configures the T1/E1 controller to support CCS cross-connect or CCS frame-forwarding.

voice-card

To configure a voice card and enter voice-card configuration mode, enter the voice-card command.

voice-card slot

Syntax Description

slot

On the Cisco 2600 and 3600 platforms:

  • A value from 0 to 3 that identifies the physical slot in the chassis where the voice card is located.

On Cisco MC3810 concentrators with one or two HCMs installed:

  • Enter 0 only; this applies to the entire chassis.

Command Modes

Global configuration

Command History

Release Modification

12.0(5)XK

The command was introduced for the Cisco 2600 and 3600 series.

12.0(7)T

This command was implemented in the 12.0(7)T release.

12.0(7)XK

This command was first supported on the Cisco MC3810 series.

12.1(2)T

This command was implemented in the 12.1(2)T release.

Usage Guidelines

You can configure codec complexity only in voice-card configuration mode. On the Cisco 2600 and 3600 series, the slot corresponds to the physical slot in the chassis. On the Cisco MC3810 series, the slot is always 0, and all changes made in voice-card mode apply to the entire Cisco MC3810. On Cisco MC3810 series concentrators, this command is available only if the chassis is equipped with one or two HCMs.

Examples

The following example enters voice-card configuration mode for the voice card in slot 1 on a Cisco 2600 or 3600 router:

router(config)# voice-card 1
router(config-voicecard)#

The following example enters voice-card configuration mode on a Cisco MC3810 concentrator:

router(config)# voice-card 0
router(config-voicecard)#

Related Commands

Command Description

codec complexity

Matches the DSP complexity packaging to the codec(s) to be supported. Codec complexity changes are made in the voice-card configuration mode.


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Posted: Fri Jun 16 15:06:48 PDT 2000
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