Table of Contents

Setting Up a Voice Connection
Configuring Voice Channel Redundancy
Using VAD and Configuring Voice Channel Utilization
Summary of Commands
addcon
cnfchadv
cnfchdl
cnfchec
cnfchfax
cnfchgn
cnfcond
cnflnpass
cnfrcvsig
cnfvchtp
cnfxmtsig
delcon
dspchcnf
dspchdlcnf
dspchec
dspcon
dspcond
dspcons
dspconst
dsprtcache
dspsigqual
dspsvcst
prtchcnf
prtchdlcnf
prtcons

Voice Connections

The voice commands apply to setting up and configuring, and statistical reporting for voice connections (including FAX). In addition to the command descriptions, this chapter describes how to add a voice connection, configure card redundancy, and optimize the use of voice activity detection (VAD). A list of the commands that let you modify most characteristics of voice and data connections also appears at the front of the chapter. Use this list as a guideline for building voice service.

Voice connections exist as ports on circuit lines that are supported by a Channelized Voice Module (CVM) or Universal Voice Module (UVM) in an IGX node. The back card for the CDP or CVM is either a BC-T1, BC-E1, or BC-J1. For the UVM, the back card is either a BC-UVI-2T1EC, a BC-UVI-2J1EC, or BC-UVI-2E1EC.

Setting Up a Voice Connection

The following steps describe how to set up a voice connection.

Step 1   Configure the voice channel at each end of the connection. The associated commands are:

Step 2   Add the connections with the addcon command. You must complete the appropriate steps at each end by using the commands in the preceding list before you add connections.

Configuring Voice Channel Redundancy

You can configure voice cards for redundancy by installing two identical card sets in adjacent slots and connecting them to the CPE through a Y-cable. Configure redundancy by using addyred. Note that a switch to a standby UVM that has active CAS-switching causes the loss of all call states.

Using VAD and Configuring Voice Channel Utilization

The bandwidth savings you gain by using VAD are less than optimal if you do not set the utilization of the voice channels to a reasonable value. To configure the utilization, use the cnfchutl command.

Summary of Commands

Table 6-1 shows the command name and starting page for the description of each command.

addcon

Establishes the channel connections between nodes in the network. You can add voice connections to any slot that has a CDP, UVM, or CVM. Before you add a connection, determine its compression type.

If you plan for a port on a UVM to carry more than 16 channels with LDCELP or the G.729 version of CACELP, you must have a second, connected UVM and configure the resultant pair of UVMs for passthrough operation. If you attempt to add more than 16 LDCELP or G.729 channels, the system reports any excess connections as being failed connections after addcon execution finishes. Furthermore, if you execute dspcon, the status display for the excess connections shows "ConnRJ" (connection rejected). Refer to the cnflnpass description in this chapter and the UVM description in the Cisco IGX Reference for a description of passthrough.

After you have established passthrough for a pair of UVM card sets, the system does not allow duplication of channel numbers when you add connections. For example, if you add 7.1.1-16, the node does not allow you to add 8.1.1-8 if you have linked the UVMs by using cnflnpass. Instead, you would add 8.1.17-24.

A UVM with Model B or higher firmware supports CAS switching. Before you can add connections in a network with CAS switching, you must configure the UVM for this feature with the cnfcassw command. Note that, for CAS switching, you use addcon to add the signaling channels at the near and far end in the format slot.port.24 on a T1 line and slot.port.16 on an E1 line. Also, the connection type for these signaling channels is "t." If you specify D-channel compression, the connection type is "td." See the description of cnfcassw in the "Setting Up Lines" chapter or, for a more detailed description, the manual titled Cisco VNS (Voice Network Switching) Installation and Operation.

Connections are added with a default class of service (COS). The value of COS is the number of seconds that the node waits before it reroutes the connection after a failure. The COS applies to various types of connections other than voice and therefore is described elsewhere (see the cnfcos description in the "Optimizing Traffic Routing and Bandwidth" chapter.)

Table 6-2 describes what you enter for the type parameter for each rate and compression variable.

Connection type is "v," "class of service" (COS) is "2," compression is VAD, and ownership is local. For an explanation of COS, see the cnfcos description in the "Optimizing Traffic Routing and Bandwidth" chapter. Because you are entering the addcon command at node alpha, the node alpha is the owner of the connection.

System Response

cnfchadv

Enables the adaptive voice (ADV) feature for individual channels. ADV must also be enabled at each node that terminates the connection. The channel-specific cnfchadv has no effect at nodes that do not support ADV enabled.

If the ADV feature is enabled for a channel with a "c" or "v" connections, VAD is automatically disabled on that channel when trunk bandwidth is available and enabled when trunk bandwidth is needed. If the Adaptive Voice feature is not enabled for a channel with a "c" or "v" connections, VAD is always turned on for that channel. In order for a voice ("c" or "v") connection to use ADV, both ends must have ADV enabled with the cnfchadv command.

Full Name

Configure channel adaptive voice

Syntax

cnfchadv <channel(s)> <y/n>

Related Commands

dspchcnf

Attributes

Example 1

cnfchadv 14.1 e

Description

Enable Adaptive Voice for channel 14.1.

System Response

cnfchdl

Configures the dial type for a channel or set of channels. The dial type may be inband, pulse, or user-configured. The user-configured option allows non-default timing values to be used. The parameters associated with the cnfchdl command are timing constants used to ensure that signaling pulses are not distorted in time by transmission through the network.

• Dial type determines the signaling message timing for a connection. Dial type is ignored for DS0 data connections.
  
  
• When you add an inband or pulse dial type to a channel, the channel configuration screen appears, showing the designated dial types for each channel.
  
  
• When you add a user-configured dial type, a more detailed screen appears, showing the dial type as well as the signaling delay, minimum wink, interdigit times, and playout delay.
  
  

If you select inband, the node assumes that the A and B bits are not used for loop-disconnect dialing. Therefore, any change in signaling bit status goes in a packet to the far end of the connection.

If you select pulse, the transmitting node waits (normally 72 ms) after an A or B bit transition for another transition to arrive. If a transition arrives, the new transition goes into the same signaling packet that is sent to the far end of the connection. This step increases the delay of the signaling transition across the network but decreases the amount of trunk bandwidth used for signaling.

If the default timings are not correct for the network, you must configure the options. The dialing type should be set correctly. If a connection-designated pulse is used for inband signaling, a greater than necessary delay across the network results. If a connection-designated inband is used for pulse signaling, the relative timing of signaling transitions may be lost and so distort the pulses.

Full Name

Configure dial type for channels

Syntax

cnfchdl <channel(s)> <dial_type> [<sig_delay> <min_wink> <int_dig_time>
<playout delay>]

Related Commands

dspchcnf, dspchdlcnf

Attributes

Example 1

cnfchdl 14.1 p

Description

Configure the dial type of channel 14.1 to pulse.

System Response

cnfchec

Configures the echo canceller and other channel parameters associated with a voice channel. (You cannot configure CAS and data channels using cnfchec). The CDP/CVM and UVM have slightly different parameters. Unavailable parameters appear on the screen as a dashed line, so no prompts for these unavailable options appear.

Full Name

Configure channel echo canceller

Syntax

For CDP/CVM:

cnfchec <chan> <ec> <erl> <td> <convergence> <nlp>

For UVM:

cnfchec <chan> <ec> <td> <nlp> <bkgd_filter>

Related Commands

dspchec

Attributes

Example 1

cnfchec 7.1 e h e e e

Description

Enable and configure the Echo Canceller in channel 7.1 with high echo loss tone disabled, convergence enabled, and non-linear processing enabled. In this example, the card is either a CDP or CVM because the channel is specified with slot.channel rather than slot.line.channel.

System Response

Example 2

cnfchec 13.1.1 e

Description

Enable the echo canceller in channel 13.1.1. In this example, the card is a UVM because the channel is specified with slot.line.channel. Note the available parameters differ slightly from a CDP/CVM.

System Response

cnfchfax

Configures a channel on a UVM for either FAX detection or FAX relay. If you enable FAX detection, the UVM suspends voice compression when it detects a FAX or modem tone on the channel. For the duration of the FAX, transmission takes place at 64 Kbps.

FAX relay is a mechanism for compression the FAX transmission rate across a network to 9.6 Kbps.

To view the current configuration, use the dspchcnf command.

Full Name

Configure FAX modem detection for channels

Syntax

cnfchfax <slot.line> <channel(s)> <e/d>

Related Command

dspchcnf

Attributes

Example 1

cnfchfax 7.1.1

Description

Configure channels 1-24 on line 1 of the UVM in slot 7 to have FAX modem detection.

System Response

cnfchgn

Configures the amount of gain inserted by the IGX node for a given circuit line channel or range of channels. Gain can be configured between +6 dB and -8 dB. The input gain is inserted at the receive side of a voice card and is therefore applied before the signal is packetized by the card. The output gain is inserted at the transmit side of a voice card and is applied after the signal has been depacketized by the card. Gain is meaningless for channel that carry data.

Full Name

Configure gain insertion for channels

Syntax

cnfchgn <channel(s)> <input_gain> <output_gain>

Related Commands

dspchcnf

Attributes

Example 1

cnfchgn 14.1 -4 2

Description

Configure input gain of -4 db and an output gain of +2 dB for channel 1 of circuit line 1.

System Response

cnfcond

Creates a conditioning template that specifies the bit patterns to be transmitted for each of the T1 and E1 timeslots and their A, B, C, and D signaling bits while the channel is in the failed state. Its purpose is to prevent the signaling bits from returning to the idle (on-hook) bit pattern during a channel failure and to force a known bit pattern (usually busy). If a connection fails and the template has been specified as the conditioning template for the failed connection, the data parameter in the template is transmitted in the channels timeslot, and the A, B, C, and D bits are processed according to the specified parameters.

A two-character sequence in the id parameter field identifies the template. The 'Data Pattern' field displays the pattern transmitted in the channels timeslot. The 'signaling Pattern' field displays the pattern transmitted in the channel's A, B, C, and D signaling bit positions. Each of the A, B, C, and D signaling bits are specified independently and may be held high or low or toggled to the on-hook condition for a short time then off-hook (the name of this latter action is a wink). You can control the timing of the bit-toggling by specifying the duration of winks in increments of 50 ms.

A typical failure response is for the node to:

1. Transmit idle characters in the channel's timeslot

2. Signal off-hook for a period of 2 seconds

3. Return permanently to the on-hook condition.

Full Name

Configure conditioning template

Syntax

cnfcond <id> <data> <A bit> <B bit> <C bit> <D bit>

Related Commands

cnfvchtp, dspchcnf, dspcond

Attributes

Example 1

cnfcond lm 01010100 0(40)/1 1 1 1

Description

Configure the conditioning template.

System Response

cnflnpass

Configures a pair of ports so that unprocessed channels go from a primary UVM to a secondary UVM. The cnflnpass command primarily applies to channels that use LDCELP or G.729 CACELP (although passthrough is possible on any type of connection except t-type or td-type). For a description of passthrough, refer to the UVM description in the Cisco IGX Reference.

To return ports to the non-passing configuration, execute cnflnpass with a 0 as the second argument.

Full Name

Configure line passthrough

Syntax

To configure passthrough, enter:

cnflnpass <primary line> <secondary line>

To remove passthrough from the primary and secondary lines, enter:

cnflnpass <primary line> 0

Related Commands

dsplncnf

Attributes

Example 1

cnflnpass 13.1 12.1

Description

Configure line 13.1 to pass any unsupported channels to line 12.1.

System Response

Upon successful execution of the command, the screen displays the slot and line of the passing channel on the right. The screen also shows other characteristics of the line.

Note that, when you remove passthrough by entering a 0 for the secondary line, the screen also still line characteristics but with dashed lines in the column for the secondary (or passing) line.

cnfrcvsig

Configures the receive signaling bits for a voice channel. Channel signaling bit options are t (transparent), 0, 1, or I (invert). If signaling is set to "not used" (-) by cnfchtp, the following condition is maintained: A=1, B=1, C=0, D=1.

Full Name

Configure receive signaling

Syntax

cnfrcvsig <channel(s)> <[A/]Conv> <[B/]Conv> <[C/]Conv> <[D/]Conv>

Related Commands

cnfxmtsig, dspsigqual

Attributes

Example 1

cnfrcvsig 8.1 A/T B/0 C/I D/I

Description

Configure channel 8.1 signaling to transparent for the A bit, inhibited for the B bit, inverted for the C and D bits.

System Response

cnfvchtp

Configures an interface signaling type for a voice channel. Most standard signaling types are maintained by the node, but a custom template may be built by the user. If you enter the cnfvchtp command without a specific interface number, the system will present you with a list of valid interface types and their associated onhook and conditioning information.

To assign an interface type (and its associated onhook and conditioning information) to the channel or set of channels, enter the number of the desired interface type. As mentioned previously, type "1" requires user configuration. Interface type is ignored for "d" type connections.

Full Name

Configure interface type for voice channels

Syntax

cnfvchtp <channel(s)> <type> [<A> <B> <C> <D> <cond_code>]

Related Commands

cnfchgn, cnfchdl, dspchcnf

Attributes

Example 1

cnfvchtp 7.1.1

Description

Configure the interface type for channel 7.1.1-24.

System Response

Example 2

cnfvchtp 15.5-8 1 X X - - b

Description

Configure a user configurable interface type for channel 15.1 to 15.8. The channel configuration screen shows that channels 5-8 of circuit line 15 now has a user-configured interface type with an Abit on-hook value of "X", a B-bit on-hook value of "X", an C-bit on-hook value of not used, D-bit on-hook value of not used, and conditioning template b.

cnfxmtsig

Allows the node to pass A, B, C, and D channel signaling bits through unchanged, or to invert, or hold them at a given value for a CDP or CVM line. It affects signaling bits in the transmit direction (to the PBX or channel bank) in an E1 system. The command configures the transmit signaling. Channel signaling bit options are T (transparent), 0, 1, or I (invert). If signaling is set to "not used" (-) by cnfchtp, the following is maintained: A=1, B=1, C=0, D=1.

Full Name

Configure transmit signaling

Syntax

cnfxmtsig <channel(s)> <[A/]Conv> <[B/]Conv> <[C/]Conv> <[D/]Conv>

Related Commands

cnfrcvsig, dspsigqual

Attributes

Example 1

cnfxmtsig 8.1 a/I b/0 c/1 d/t

Description

Configure the transmit signaling for channel 8.1 to inverted for the A bit, inhibited for the B bit, asserted for the C bit and transparent for the D bit.

System Response

delcon

Removes one or more voice connections from a network. You can delete connections at either end of the connection.

Do not delete a connection when the node at the other end of the connection is unreachable. The unreachable node does not recognize the deletion.

Also, you must not delete a connection to an unreachable node then connect that deleted channel to another node.

Full Name

Delete connection

Syntax

delcon <channel(s)>

Related Commands

addcon, dspcon, dspcons

Attributes

Example 1

delcon 14.1

Description

Delete connection 14.1. The proposed deletions are highlighted, a prompt requests confirmation of the deletion. Enter a "y" to delete the highlighted connections or an "n" to keep the highlighted connections. The example shows the screen after deletion of 14.1.

System Response

dspchcnf

Displays configuration details for voice, data, or Frame Relay channels. When you specify a voice channel with dspchcnf, the display shows:

• Percent of channel utilization
  
  
• Adaptive voice enable status
  
  
• Fax enable status
  
  
• Gain in both directions (in decibels)
  
  
• Dial Type
  
  
• Interface type (such as 2w E&M)
  
  
• Onhook and conditioning specifications
  
  

For the contents of the display when you apply dspchcnf to a serial data channel or Frame Relay channel, refer to the chapters in this manual that describe those traffic types.

Full Name

Display channel configuration

Syntax

dspchcnf <start_channel>

Related Commands

cnfchadv, cnfchdfm, cnfchdl, cnfcheia, cnfchgn, cnfchtp, cnfchutl

Attributes

Example 1

dpchcnf 7.1.1

Description

Display the channel configuration of line 7.1.1-24. The card in slot 7 is a UVM.

System Response

Example 2

dspchcnf 9.1.3-8

Description

Display configuration values for all channels on Frame Relay port 9.1 (which also shows if a data channel is configured for idle code suppression).

dspchdlcnf

Displays dial type configurations for all channels on a circuit line as follows:

Full Name

Display channel dial type configurations

Syntax

dspchdlcnf <start_channel>

Related Commands

cnfchdl

Attributes

Example 1

dspchdlcnf 14.1

Description

Display the dial type configuration for all channels beginning with 14.1.

System Response

dspchec

Displays the integrated echo canceller (IEC) parameters for one or more voice channel(s). The dspchec command does not apply to CAS or data channels. The specified channels must be on a CDP, CVM, or UVM. Table 6-24 lists the displayed parameters and possible values.

dspcon

Displays connection information for a specified channel. The information displayed includes:

• The channel numbers for both the local and remote ends of the connection.
  
  
• The node names at both ends of the connection.
  
  
• The routing restriction.
  
  
• The class of service (COS) of the connection (see cnfcos description for details).
  
  
• The connection route listing the end nodes and any intermediate nodes.
  
  
• The preferred route for the connection (if configured).
  
  
• If cost-based routing cost-based routing is configured, displays maximum and current costs for a connection route.
  
  
• The status of the cards associated with the connection.
  
  
• Any Y-cable conflicts.
  
  
• The type of the compression, if applicable (VAD, ADPCM, LDCELP, CACELP for voice; repetitive pattern suppression (RPS) applies to data connections).
  
  

The status that may be displayed includes:

Full Name

Display connection

Syntax

dspcon <channel>

Related Commands

addcon, cnfrtcost, cnfpref

Attributes

Example 1

dspcon 6.1

Description

Display connection information for 6.1.

System Response

dspcond

Displays the signaling bit patterns from the specified template. Refer to the description of the cnfcond command for the purpose of the conditioning template.

Full Name

Display conditioning criteria

Syntax

dspcond <identifier>

Related Commands

cnfchtp, cnfcond

Attributes

Example 1

dspcond a

Description

Display the conditioning template identified as "a."

System Response

dspcons

Displays a summary of the connections on an IGX node. Table 6-27 shows the fields displayed in the dspcons screens.

The dspcons screen in Example 3 shows whether the Idle Code Suppression feature is enabled or disabled. The Idle Code Suppression feature provides a way to stop fast packet generation on an Nx64 super-rate PVC connection when the connected PBX has terminated a video call. Traffic on the data network will therefore be reduced. Bursty data will be able to use this unused bandwidth.

On the dspcons screen, data connections show the word "ICS" under the "Compress" field if the connection has idle code suppression enabled or not. This feature is supported only on IGX platforms in Release 9.2. It is supported only on the UVM and CDP/CVM cards. The UVM model E and CVM/CDP model B revision E firmware are required to use the Idle Code Suppression feature in Release 9.2.

dspconst

Displays the status of the circuit line(s) and continues to display the status until you press the Delete key. While the display is on the screen, the status is automatically updated. The update frequency is one second for each circuit line being displayed. (For example, if only one line is displayed, the update frequency is once per second, if three circuit lines are displayed, the update frequency is once per three seconds). Table 6-29 shows the connection type. cnfchtp must be correctly configured.

dsprtcache

This command displays the cache of all cost-based routing connections. The optional index parameter lets you specify a cache entry index. The optional c parameter clears the cache. The information displayed includes:

Full Name

Display cost-based route cache

Syntax

dsprtcache [index] [c]

[index] specifies the cache entry index

[c] specifies to clear the entire cache or a single entry

Related Commands

dspcon, cnfrtcost, cnfpref

Attributes

Example 1

dsprtcache

Description

Display route cache contents, and let you monitor and manually clear the cache.

System Response

dspsigqual

Displays the configuration for the A, B, C, and D bit signaling qualifiers for all channels. The only parameter is the starting channel. You set the values for these signaling bits with the cnfrcvsig and cnfxmtsig commands. Note that these signaling bit states are different from the states during circuit alarm (signaling conditioning).

During normal operation of the voice circuit, the A, B, C, and D signaling bits may be held at a fixed value (0 or 1), inverted (I), or passed through transparently (T). For the direction of the signals, the transmit direction is towards the PBX or channel bank. Receive is from the external equipment.

Full Name

Display signaling qualifiers

Syntax

dspsigqual <start channel>

Related Commands

cnfxmtsig, cnfrcvsig

Attributes

Example 1

dspsigqual 8.1

Description

Display the channel signaling bit qualifiers for channel 8.1.

System Response

dspsvcst

Displays the voice SVC statistics.

Full Name

Display voice SVC statistics

Syntax

dspsvcst

Related Commands

None

Attributes

Example 1

dspsvcst

Description

Display the voice SVC statistics for the current node.

System Response

prtchcnf

Prints the configuration details for voice channels or data channels. This command uses the same syntax, and prints the same information as is displayed using the dspchcnf command. See the dspchcnf command for syntax and output information.

Full Name

Print channel configurations

Syntax

prtchcnf [start_channel]

Related Commands

dspchcnf

Attributes

Example 1

prtchcnf 14.1

Description

Print the configuration values of circuit line 14.1.

System Response

None available because this command produces hardcopy.

prtchdlcnf

Prints the dial type configurations for channels on a circuit line.

Full Name

Print dial type configuration for channels

Syntax

prtchdlcnf <start_channel>

Related Commands

cnfchdl, dspchcnf

Attributes

Example 1

prtchcnf 14.1

Description

Print the dial type configuration for all channels beginning with 14.1.

System Response

None available as this command produces hardcopy.

prtcons

Prints a summary of connections terminated at the IGX node.

Full Name

Print connections

Syntax

prtcons [start_channel] [nodename] [type]

Related Commands

dspcons

Attributes

Example 1

prtcons

Description

Print a summary of all connections.

System Response

None available as this command produces hardcopy.

Posted: Fri Nov 8 07:08:39 PST 2002
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