Cisco MC3810 Multiservice Concentrator Configuration Guide - Voice Port Configuration [Cisco MC3810 Multiservice Access Concentrators]

Table Of Contents

Configuring Voice Ports

Basic Voice-Port Configuration

Determine Your Voice-Port Configuration

Configuring the Basic Voice-Port Settings

Verify Your Voice-Port Configuration

Configuring Voice-Port Tuning Options

General Voice-Port Tuning Options

Tuning FXO Ports

Tuning FXS Ports

Tuning E&M Ports

Configuring Voice Ports

The Cisco MC3810 multiservice access concentrator has two different hardware configurations for voice ports:

•Six analog voice interfaces

•One digital voice module (T1/E1)

This chapter describes:

•Basic Voice-Port Configuration

•Configuring Voice-Port Tuning Options

Note The Call Detail Records (CDR) functionality is enabled by default. If you do not plan to use the CDR functionality to compile call detail records, it is recommended that you disable CDR by entering the configuration command dial-control-mib max-size 0. For more information, see Chapter 12, "Configuring the Cisco MC3810 to Compile Call Detail Records."

Before performing the voice-port configuration, verify that your Cisco MC3810 includes either the six analog voice interfaces or the single digital voice interface.

For both analog and digital voice ports, the Cisco MC3810 provides support for three basic voice signaling formats:

•FXO—The Foreign Exchange Office interface allows a connection to be directed to the PSTN's central office. The FXO interface also allows a connection to be directed to a standard PBX interface or if the local telecommunications authority permits. The FXO interface can also be connected to analog PBX station lines. This interface is of value for Off-Premises eXtension (OPX) applications.

•FXS—The Foreign Exchange Station interface allows connection for basic telephone equipment, and keysets, and supplies ring, voltage, and dial tone. The FXS interface can be connected to standard analog PBX central office/network trunk ports.

•E&M—The recEive and transMit interface allows connection for PBX trunk lines (tie lines). E&M is a signaling technique for two-wire and four-wire telephone and trunk interfaces.

The DVM supports Channel Associated Signaling (CAS) for both FXO and FXS. For E&M, the DVM supports E1 Mercury Exchange Limited Channel Associated Signaling (MELCAS).

The Cisco MC3810 supports up to six analog personality modules (APMs) with each APM supporting a single voice signaling type. You can install the FXO, FXS, and E&M APMs in any combination. The digital voice port also supports all three signaling formats. For more information about the APM hardware, see the Cisco MC3810 Multiservice Access Concentrator Hardware Installation Guide.

Under most circumstances, the default voice-port command values are adequate to configure FXO and FXS ports to transport voice data over your existing network. 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.

Note Configuration for analog and digital voice-ports is very similar. However, if you are configuring digital voice ports, you must also configure the CAS group to assign which timeslots are assigned which voice signaling protocol. For more information about CAS configuration, see "Configuring Support for PBX Signaling Formats."

Basic Voice-Port Configuration

This section describes the minimum configuration tasks required to configure the Cisco MC3810 voice ports. These procedures apply to all three primary voice signaling types (FXO, FXS, and E&M).

Determine Your Voice-Port Configuration

Before entering voice-port configuration mode, enter:
router> show voice port
Using this command, you can determine:

•APM types installed in each physical port

•Available port numbers for your voice ports

•Default configuration

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

Table 10-1 Voice Interface Slot and Port Numbers

Interface Type

Slot

Valid Port Numbers

Analog voice module (AVM)

1

1-6

Digital voice module (DVM)¹

1

Digital T1: 1-24

Digital E1: 1-15 and 17-31

Multiflex trunk module (MFT)²

0

Digital T1: 1-24

Digital E1: 1-15 and 17-31

¹Used for the interface to the local phone device or PBX.

²Used for the interface to the WAN.

Figure 10-1 shows the analog voice ports, and the valid slot/port number designations for each.

Figure 10-1 Slot/Port Designations for Analog Voice Ports

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.

Timesaver To help you keep track of the voice ports while configuring them, you can use the analog and digital voice-port planning forms in "Planning Forms." Using the displays from the show voice port or show voice port summary commands, write down the voice module or signaling type next to the slot/port number to help you configure each voice port. This will help you in configuring the voice ports because you must enter the correct slot/port number to enter voice-port configuration mode. Also, using the planning forms, you can plan the connection type and destination phone number for each voice port.

Configuring the Basic Voice-Port Settings

The procedure for configuring basic voice-port settings depends on whether the Cisco MC3810 has the analog voice module (AVM), or whether the Cisco MC3810 is a digital voice version with the digital voice module (DVM) or multiflex trunk module (MFT) installed. This section is divided into the following two procedures:

•Configuring Basic Voice-Port Settings for Analog Voice Ports

•Configuring Required Voice-Port Settings for Digital Voice Ports

Configuring Basic Voice-Port Settings for Analog Voice Ports

When configuring analog voice ports, a set of commands are required and are the minimum commands necessary to configure the voice port. Another set of commands to configure basic voice-port settings for analog voice ports are optional depending on your configuration. This section is divided into the following procedures:

•Configuring Required Voice-Port Settings for Analog Voice Ports

•Configuring Optional Voice-Port Settings for Analog Voice Ports

•Activating the Analog Voice Port

Configuring Required Voice-Port Settings for Analog Voice Ports

To configure the required voice-port settings for analog voice ports, complete the following tasks from global configuration mode:
Step

Command

Purpose
1
router(config)# voice-port 
slot/port
Enter voice-port configuration mode. The voice-port configuration commands are nested so that all subsequent commands affect only the specified voice port.

The slot number for analog voice ports on the Cisco MC3810 is always 1. There is no port 0 for voice ports.
2
router(config-voiceport)# codec 
{g729r8 | g729ar8 | g726r32 | 
g711alaw | g711ulaw}
(Optional) Configure 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, while the g729r8 value can only support a maximum of 12.

The g729r8 and g729ar8 compression modes have a nominal data rate of 8 kbps. The g726r32 compression mode has a nominal data rate of 32 kbps. The g711alaw and g711ulaw compression modes have a nominal data rate of 64 kbps.
3
router(config-voiceport)# 
connection {tie-line | plar | 
plar-opx} string
Configure the voice-port connection mode type. If the connection will be to a PBX, use the tie-line option. If the connection will be for Private Line Auto Ringdown (PLAR), use the plar option.

If the connection will be for PLAR Off-Premises eXtension (OPX), use the plar-opx option. Using this option, the local voice port will provide a local response before the remote voice port receives an answer. For this option, FXO interfaces will not answer until the remote side answers.

Note After a transparent Common Channel Signaling (CCS) connection is configured by entering the connection plar command, any change to the configuration after that will not take place until the connection is shut down and then restarted with a shutdown command and a no shutdown command. For example, the phone number supplied in the plar command can be changed while the connection is in no shutdown state, but the change will not cause the current connection to be closed and a new connection opened to the new phone number. This will only take effect on the next no shutdown command after a shutdown command.
To configure optional voice-port settings for analog voice ports, proceed to the next section.

Configuring Optional Voice-Port Settings for Analog Voice Ports

To configure the optional voice-port settings for analog voice ports, complete the following tasks while in voice-port configuration mode:
Step

Command

Purpose
1
router(config-voiceport)# voice 
confirmation-tone
If you configured the connection command for PLAR or PLAR OPX, you can disable the two-beep confirmation tone that a caller hears when picking up the handset.

This command applies only when a port is configured for PLAR to draw the dial tone from a remote PBX.
2

If you want to change the default signaling type for the voice port, enter one of the following:
router(config-voiceport)# signal 
{loop-start | ground-start}
Configure the signaling type for the FXO and FXS voice ports. The default is loop-start.
router(config-voiceport)# signal 
{wink-start | immediate | 
delay-dial}
Configure the signaling type for the E&M voice ports. The default is wink-start.
3
router(config-voiceport)# 
dial-type {pulse | dtmf}
Configure the voice-port dial type. The default is dtmf (FXO and E&M voice ports only).

If you configure the voice port to support pulse dialing, the different voice port signaling types handle pulse in the following way:

•FXO—Transmits but does not receive pulse dialing

•FXS—Does not transmit, but receives pulse dialing

•E&M—Transmits and receives pulse dialing
4
router(config-voiceport)# cptone 
country
Configure the call progress tone. Using this command, configure the voice port for the local territory's call progress tone setting. The call progress tone setting determines the settings for dialtone, busytone, and ringback tone. The call progress tone is different from the dual tone multifrequency (DTMF) tone.

The default for this command is northamerica. For a list of supported countries, see the Cisco IOS Voice, Video, and Home Applications Command Reference.
5
router(config-voiceport)# 
description LINE
Enter a string description for the voice port for the LINE value. The string describes the voice port in displays. You can use the description command to note the voice port's location or use.
Activating the Analog Voice Port

To activate the analog voice port, enter the following command in voice-port configuration mode:
Step

Command

Purpose
1
router(config-voiceport)# no 
shutdown
Activate the voice port. You should only activate voice ports you are planning to use.
After you have configured the basic voice-port settings, choose one of the following:

•To configure tuning options for this voice port, remain in voice-port configuration mode and proceed to the "Configuring Voice-Port Tuning Options" section.

•To configure another voice port, exit voice-port mode (for this voice-port) by entering the Exit command.

From configuration mode, you can reenter voice-port configuration mode by entering a new voice-port slot/port number.

This completes the basic analog voice-port configuration.

Configuring Required Voice-Port Settings for Digital Voice Ports

To configure the required voice-port settings for digital voice ports, complete the following tasks from global configuration mode:
Step

Command

Purpose
1
router(config)# controller  
{t1 | e1} number
Enter controller configuration mode.

Specify whether your controller is E1 or T1, and enter the controller number. The number should be 0 if the controller is for the interface to the local phone device or PBX (through the DVM). The number should be 1 for the interface to the WAN (through the MFT).
2
router(config-controller)# mode 
cas
Configure the T1/E1 line to support CAS.

Note This procedure does not configure support for Q.SIG PBX signaling. For more information, see "Configuring Support for PBX Signaling Formats."
3
router(config-controller-cas)# 
voice-group  voice-group-no  
timeslots timeslot-list type 
{e&m-immediate | e&m-delay | 
e&m-wink | e&m-melcas | 
fxs-ground-start | 
fxs-loop-start | fxs-melcas | 
fxo-ground-start | 
fxo-loop-start | fxo-melcas)
Configure a list of timeslots to form a CAS group for the T1/E1 line. The "melcas" options are supported only on E1 and apply to the Mercury Exchange Limited (MEL) standard, used primarily in the United Kingdom.

When configuring a CAS group for a T1/E1 line to a PBX, make sure the channel numbers configured match the channels on the PBX. Contact the PBX administrator to determine which channels to use.

Note If the mode cas command is not entered, the voice-group command is not visible when you enter a question mark (?) to display available controller-cas commands.
4

Repeat step 3 for each CAS group defined. After the CAS groups are defined, exit CAS controller configuration mode.
This completes the required digital voice-port configuration.

Configuring Optional Voice-Port Settings for Digital Voice Ports

To configure the optional voice-port settings for digital voice ports, complete the following tasks beginning in configuration mode:
Step

Command

Purpose
1
router(config)# voice-port 
slot/port
Enter voice-port configuration mode. The voice-port configuration commands are nested so that all subsequent commands affect only the specified voice port.

The slot number should be 0 if the voice port is for the interface to the local phone device or PBX (through the DVM). The slot number should be 1 for the interface to the WAN (through the MFT). The slot number should match the number value entered in the controller {t1 | e1} command.

For digital T1, valid port numbers are 1-24. For digital E1, valid port numbers are 1-15 and 17-31.
2
router(config-voiceport)# 
dial-type {pulse | dtmf}
Configure the voice-port dial type. The default is dtmf (FXO and E&M voice ports only).

If you configure the voice port to support pulse dialing, the different voice port signaling types handle pulse in the following way:

•FXO—Transmits but does not receive pulse dialing

•FXS—Does not transmit, but receives pulse dialing

•E&M—Transmits and receives pulse dialing
3
router(config-voiceport)# 
compand-type {u-law | a-law}
Configure the companding standard to convert between analog and digital signals in PCM systems. The default is u-law, which specifies the North American mu-law ITU-T PCM encoding standard. Specify a-law to use the European a-law ITU-T PCM encoding standard.
4
router(config-voiceport)# 
description LINE
Enter a string description for the voice port for the LINE value. The string describes the voice port in displays. You can use the description command to note the voice port's location or use.
Activating the Digital Voice Port

To activate the analog voice port, enter the following command in voice-port configuration mode:
Step

Command

Purpose
1
router(config-voiceport)# no 
shutdown
Activate the voice port. You should only activate voice ports you are planning to use.
After you have configured the basic voice-port settings, choose one of the following:

•To configure tuning options for this voice port, remain in voice-port configuration mode and proceed to the "Configuring Voice-Port Tuning Options" section.

•To configure another voice port, exit voice-port mode (for this voice-port) by entering the Exit command.

From configuration mode, you can reenter voice-port configuration mode by entering a new voice-port slot/port number.

This completes the basic digital voice-port configuration.

Verify Your Voice-Port Configuration

You can check the validity of your voice-port configuration by doing the following tasks:

•Pick up the handset of an attached telephony device and check for a dial tone.

•If you have dial tone, check for DTMF detection. If the dial tone stops when you dial a digit, then the voice-port is most likely configured properly.

•Use the show voice port [slot/port] and show voice port summary EXEC commands to verify that the voice-port configuration is correct.

•Use the show voice dsp EXEC command to verify the current status of all Digital Signaling Processor (DSP) voice channels.

•Use the show voice call summary EXEC command to verify the call status for all voice ports.

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 doing the following:

•Ping the associated IP address to confirm connectivity. If you cannot successfully ping your destination, refer to the "Configuring IP" chapter in the Cisco IOS Release 12.0 Network Protocols Configuration Guide, Part 1.

•Use the show voice port command to make sure that the voice port is enabled. You can display information for a single voice port, for all voice ports, or a summary report. If the voice port is offline, use the no shutdown command.

•Check the dial-peer configuration (as configured in "Configuring Voice over Frame Relay," "Configuring Voice over ATM," or "Configuring Voice over HDLC").

•Check the Frame Relay, ATM, or HDLC configuration.

•Check to see if the voice network module has been correctly installed. For more information, see the Cisco MC3810 Multiservice Access Concentrator Hardware Installation Guide.

Configuring Voice-Port Tuning Options

In most cases, the default values for the voice port commands will be sufficient. However, for specific configurations, you can tune the voice port values as needed. This section describes voice-port tuning commands that cover all voice call-signaling types, and commands for specific voice-call signaling types.

General Voice-Port Tuning Options

The procedures in this section fine-tune voice-port settings for such attributes as input gain and output attenuation, support for echo cancel coverage, timeout duration settings, and timing settings. The commands in this section apply to all three voice call signaling types (FXO, FXS, and E&M).

To configure general voice-port tuning options, complete the following in voice-port configuration mode:
Step

Command

Purpose
1
router(config-voiceport)# input 
gain value
Configure the input gain value in decibels for the receiver side of the interface. The value represents the amount of gain to be inserted at the receiver side of the interface. The acceptable value is any integer from -6 to 14. The default is 0.
2
router(config-voiceport)# output 
attenuation value
Configure the output attenuation value in decibels for the transmit side of the interface. The value represents the amount of loss to be inserted at the transmit side of the interface. The acceptable value is any integer from 0 to 14. The default is 0.
3
router(config-voiceport)# 
echo-cancel enable
Enable echo cancel coverage.
4
router(config-voiceport)# 
echo-cancel coverage 
{8|16|24|32}
Configure the number of milliseconds the echo cancel will cover on a given signal. The default is 16.
5

Configure the voice-port timeout values:
router(config-voiceport)# 
timeouts initial seconds
Configure the initial timeouts 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.
router(config-voiceport)# 
timeouts interdigit seconds
Configure the interdigit timeouts 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. The default is 10 seconds. The timeouts interdigit command is used in conjunction with variable length dial plans. For more information, see the "Variable-Length Dial Plans" section.
6

If the voice-port dial type is DTMF, configure the DTMF timing values:
router(config-voiceport)# timing 
digit milliseconds
Configure the DTMF digit signal duration. The range of the DTMF digit signal duration is from 50-100. The default is 100.
router(config-voiceport)# timing 
inter-digit milliseconds
Configure the DTMF interdigit signal duration. The range of the DTMF interdigit signal duration is from 50-500. The default is 100.
7

If the voice-port dial type is pulse, configure the pulse timing values:
router(config-voiceport)# timing 
pulse digit milliseconds
Configure the pulse digit signal duration. The range of the pulse digit signal duration is from 10-20. The default is 20.
router(config-voiceport)# timing 
pulse inter-digit milliseconds
Configure the pulse inter-digit signal duration. The range of the pulse inter-digit signal duration is from 100-1000. The default is 500.
8
router(config-voiceport)# vad
Enable Voice Activity Detection (VAD) on the voice-port. By default, VAD is disabled.
9
router(config-voiceport)# 
condition {tx-a-bit | tx-b-bit | 
tx-c-bit | tx-d-bit} {rx-a-bit | 
rx-b-bit | rx-c-bit | rx-d-bit} 
{on | off | invert}
(For T1/E1 digital voice ports only.) Configure the voice port to manipulate the bit patterns sent or received by the Cisco MC3810 to match expected patterns on a connected device.

Be careful not to destroy the information content of the bit pattern. For example, forcing the A-bit on or off will prevent FXO interfaces from being able to generate both an on-hook and off-hook state.

Note The show voice port command reports at the protocol level, while the show controller command reports at the driver level. The driver is not notified of any bit manipulation using the condition command. As a result, the show controller command output will not account for the bit conditioning.
To configure tuning options for specific voice signaling types, refer to the following sections in this chapter:

•Tuning FXO Ports

•Tuning FXS Ports

•Tuning E&M Ports

Tuning FXO Ports

When configuring FXO voice-ports, there are voice-port tuning commands specific to FXO signaling. To configure tuning for FXO ports, complete the following tasks in voice-port configuration mode:
Step

Command

Purpose
1
router(config-voiceport)# 
impedance {600r|600c|900r|900c}
Configure the impedance for the FXO port (analog voice ports only). The default is 600r, for 600 ohms real.
2
router(config-voiceport)# ring 
number number
Configure the number of rings detected before a connection is closed on the FXO port.
3
router(config-voiceport)# 
timing guard-out milliseconds
Configure the timer that will prevent a new seizure from this FXO port to a remote FXS port so that the FXS port can clearly detect the disconnect signal. The valid range for the duration is 300-3000, and the default is 2000.

It is recommended that this value be set to 600 milliseconds or more.
4
router(config-voiceport)# exit
Exit voice-port configuration mode.
This completes the configuration of an FXO voice port. If you have questions or need assistance, see "Additional Documentation" on page ix.

Tuning FXS Ports

When configuring FXS voice ports, there are voice-port tuning commands specific to FXS signaling. To configure tuning for FXS ports, complete the following tasks in voice-port configuration mode:
Step

Command

Purpose

1

Configure the ring characteristics of an FXS voice port (analog ports only):
router(config-voiceport)# ring 
frequency number
Specify the ring frequency for the FXS voice port. The number value should be set to either 20 or 30.
router(config-voiceport)# ring 
cadence [on1 | off1] [on2 | 
off2] [on3 | off3] [on4 | off4] 
[on5 | off5] [on6 | off6]
Specify the local ring cadence for the FXS voice port. Using this command, you specify the on and off pulses for the ring. The ring cadence that should be configured differs depending on the local region. The values are measured in 100-millisecond units.

The default is on2 and off4, which is the default ring cadence for North America.
2
router(config-voiceport)# 
disconnect-ack
Configure the voice port to disable the sending power as an acknowledgement to the FXS after a detected on-hook signal in the connected state.
3
router(config-voiceport)# exit
Exit voice-port configuration mode.
This completes the configuration of an FXS voice port. If you have questions or need assistance, see "Additional Documentation" on page ix.

Tuning E&M Ports

When configuring E&M voice ports, there are voice-port tuning commands specific to E&M signaling. To configure tuning for E&M ports, complete the following tasks in voice-port configuration mode:
Step

Command

Purpose
1
router(config-voiceport)# 
operation {2-wire | 4-wire}
Configure the E&M cabling scheme (for analog voice ports only).
2
router(config-voiceport)# type 
{1 | 2 | 3 | 5}
Configure the E&M interface type.
3
router(config-voiceport)# timing 
wink-duration milliseconds
Configure 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 100-400 and the default is 200.
4
router(config-voiceport)# timing 
wink-wait milliseconds
Configure 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 100-5000 and the default is 200.
5
router(config-voiceport)# timing 
clear-wait milliseconds
Configure 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 100-2000 and the default is 400.
6
router(config-voiceport)# timing 
delay-duration milliseconds
Configure the timing delay-duration value. This value sets the delay signal duration for delay dial signaling. This value applies only if the signal command is set to delay-dial. The range is from 100-5000, and the default is 140.
7
router(config-voiceport)# timing 
delay-start milliseconds
Configure 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 20-2000 and the default is 150.
8
router(config-voiceport)# timing 
dialout-delay milliseconds
Configure the timing dialout-delay value. This value sets the delay interval before sending a dial digit or cut-through. This value applies only if the signal command is set to immediate. The range is from 100-5000, and the default is 300.
9
router(config-voiceport)# exit
Exit voice-port configuration mode.
Note The show voice port command reports at the protocol level while the show controller command reports at the driver level. The driver is not notified of any bit manipulation using the ignore and define commands. As a result, the show controller command display output will not account for the bit pattern definition.

This completes the configuration of an E&M voice port. If you have questions or need assistance, see "Additional Documentation" on page ix.