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Table Of Contents
IP Communications Voice/Fax Network Module
Prerequisites for the IP Communications Voice/Fax Network Module
Restrictions for the IP Communications Voice/Fax Network Module
Information About the IP Communications Voice/Fax Network Module
IP Communications Voice/Fax Network Module Software Modules
IP Communications Voice/Fax Network Module Capabilities
Channel Availability for DSPs Based on Codecs
How to Configure the IP Communications Voice/Fax Network Module
Configuring the Voice Card for the Flex Option on the IP Communications Voice/Fax Network Module
Configuring Digital Interfaces for the IP Communications Voice/Fax Network Module
Configuring Channel Bank Support for the IP Communications Voice/Fax Network Module
Configuration Example for IP Communications Voice/Fax Network Module
IP Communications Voice/Fax Network Module
The IP Communications Voice/Fax Network Module feature provides the ability to directly connect the PSTN and legacy telephony equipment to Cisco 2600XM series, Cisco 2691, Cisco 3600 series, and Cisco 3700 series multiservice routers, enabling applications such as IP telephony, toll bypass, and full gateway integration. The voice WAN interface cards (VWICs) supported by the new network modules include 2- and 4-port FXS; 2- and 4-port FXO; 2-port DID, E&M, and BRI (S/T); and 1- and 2-port T1/E1.
Feature History for the IP Communications Voice/Fax Network Module
Finding Support Information for Platforms and Cisco IOS Software Images
Use Cisco Feature Navigator to find information about platform support and Cisco IOS software image support. Access Cisco Feature Navigator at http://www.cisco.com/go/fn. You must have an account on Cisco.com. If you do not have an account or have forgotten your username or password, click Cancel at the login dialog box and follow the instructions that appear.
Contents
•
Prerequisites for the IP Communications Voice/Fax Network Module
•
Restrictions for the IP Communications Voice/Fax Network Module
•
Information About the IP Communications Voice/Fax Network Module
•
How to Configure the IP Communications Voice/Fax Network Module
Prerequisites for the IP Communications Voice/Fax Network Module
The recommended minimum Cisco IOS Release for this feature is Release 12.3(7)T. For optimum results, use Cisco IOS Release 12.3(11)T2.
This feature requires 32 MB of Flash memory, 1.1 MB of I/O memory, and 96 MB of RAM (128 MB of RAM is required for the Cisco 2600XM series and the Cisco 3700 series).
Restrictions for the IP Communications Voice/Fax Network Module
The IP Communications Voice/Fax Network Module feature does not currently offer echo cancellation on the VWICs configured as T1 interfaces, which may result in a degradation of service in some instances.
Information About the IP Communications Voice/Fax Network Module
This section provides information about the following:
•
IP Communications Voice/Fax Network Module Software Modules
•
IP Communications Voice/Fax Network Module Software Modules
•
Channel Availability for DSPs Based on Codecs
IP Communications Voice/Fax Network Module Software Modules
The IP Communications Voice/Fax Network Module feature is composed of software modules that offer the following features on voice network modules:
•
Channel group support for up to 32 channels
•
Flex option for configuring codec complexity—This new option allows the digital signal processor (DSP) to process up to 16 channels. In addition to continuing support for configuring a fixed number of channels per DSP, the flex option enables the DSP to handle a flexible number of channels. The total number of supported channels varies from 6 to 16, depending on which codec is used for a call. Therefore, the channel density varies from 6 per DSP (high-complexity codec) to 16 per DSP (g.711 codec).
–
Oversubscription—In flex mode, you can connect (or configure in the case of DS0 groups and PRI groups) more voice channels to the module than the DSPs can accommodate. If all voice channels should go active simultaneously, the DSPs will be oversubscribed and calls that are unable to allocate a DSP resource will fail to connect.
•
Software-based echo cancellation up to 32-millisecond conversion
•
Digital: BRI, PRI, and CAS
•
Analog: FXS, FXO, E&M, and DID
•
Signaling channel allocation
•
Voice channel allocation
•
Voice port independent channel allocation
•
Hairpinning:
–
Digital to digital (same card)
–
Analog to digital (same card)
•
Channel bank support—Analog voice ports are internally connected to a DS0 time slot on a digital T1/E1 interface. All the signaling is transparently sent between the analog voice port and DS0 time slot, and will not be seen by the higher layer voice software.
•
DSP crash recovery
•
FXO and FXS Caller ID Type 1 and Type 2
•
Trunk alarm handling
IP Communications Voice/Fax Network Module Capabilities
Table 1 provides information about the three network modules that support this feature.
Table 1 IP Communications Voice/Fax Network Module Capabilities
Module DSPs Number of Channels T1/E1 Ports Voice Interface Cards (VICs) Medium Complexity High Complexity FlexNM-HD-1V1
1
4
4
4
0
One 2- to 4-port VIC
NM-HD-2V
1
8
6
6 to 8
0
Two 2- to 4-port VICs
NM-HD-2VE
3
24
18
18 to 48
4
Two 2- to 4-port VICs or
one VIC and one T1/E1 interface VIC or
two T1/E1 interface VICs
1 Number of channels depends on the VIC module installed in the router, not the number of DSPs.
Channel Availability for DSPs Based on Codecs
Table 2 lists the number of channels available on each DSP for the codecs supported by the IP Communications Voice/Fax Network Module feature.
Table 2 Channels on DSP for Codecs Supported by the IP Communications Voice/Fax Network Module
Codec Channels per DSP High-Complexity Medium Complexity Flex ComplexityG.711 (u-law, a-law)
6
8
161
Fax/modem pass-through
6
8
16
Clear-channel codec
6
8
16
G.726 (32K, 24K, 16K)
6
8
8
GSMFR
6
8
8
Fax relay
6
8
8
G.729, G.729B, G.729A, G.729AB
6
8
8
G.728
6
Not supported
6
G.723.1 (5.3K, 6.3K)
6
Not supported
6
G.723.1A (5.3K, 6.3K)
6
Not supported
6
GSMEFR
6
Not supported
6
1 Applicable to the NM-HD-2VE only. The limitation on the number of calls is based on the network module, not the DSP (that is, even though one DSP supports 16 channels, the NM-HD-2V supports only 8 G.711 calls due to the number of analog ports).
How to Configure the IP Communications Voice/Fax Network Module
This section contains the following procedures:
•
Configuring the Voice Card for the Flex Option on the IP Communications Voice/Fax Network Module
•
Configuring Digital Interfaces for the IP Communications Voice/Fax Network Module
•
Configuring Channel Bank Support for the IP Communications Voice/Fax Network Module
Configuring the Voice Card for the Flex Option on the IP Communications Voice/Fax Network Module
To enable the IP Communications Voice/Fax Network Module feature, perform this task to configure the voice card for the flex option in codec complexity.
SUMMARY STEPS
1.
enable
2.
configure terminal
3.
voice-card slot
4.
codec complexity {flex | high | medium}
5.
voice local-bypass
6.
exit
DETAILED STEPS
Configuring Digital Interfaces for the IP Communications Voice/Fax Network Module
Perform this task to configure the digital interfaces.
SUMMARY STEPS
1.
enable
2.
configure terminal
3.
controller {t1 | e1} slot/port
4.
clock source {line [primary] | internal}
5.
framing {sf | esf}
or
framing {crc4 | no-crc4}6.
linecode {b8zs | ami}
or
linecode {ami | hdb3}7.
cablelength long {gain26 | gain36} {-15db | -22.5db | -7.5db | 0db}
or
cablelength short {133 | 266 | 399 | 533 | 655}8.
ds0-group ds0-group-number timeslots timeslot-list type {e&m-delay-dial | e&m-fgd | e&m-immediate-start | e&m-wink-start | ext-sig | fgd-eana | fgd-os | fxo-ground-start | fxo-loop-start | fxs-ground-start | fxs-loop-start | none}
or
pri-group [timeslots range]
or
channel-group channel-group-number timeslots range [speed kbps]
or
tdm-group tdm-group-number timeslots timeslot-list type {e&m | fxs [loop-start | ground-start] | fxo [loop-start | ground-start]}9.
exit
10.
connect connection-id {t1 | e1} slot/port1 tdm-group1 {t1 | e1} slot/port2 tdm-group2
11.
end
12.
no shutdown
DETAILED STEPS
Configuring Channel Bank Support for the IP Communications Voice/Fax Network Module
The channel bank feature provides support for the TDM cross-connect functionality between analog voice ports and digital DS0s on the same NM-HD-2VE using CAS signaling.
To establish a channel bank connection between an analog voice port and a T1 DS0, configure the connect (voice-port) command in global configuration mode. To verify the channel bank connection, use the show connection all command.
Restrictions
The configuration for cross-connect must be on the same network module.
A maximum of four FXS or FXO ports can be cross-connected to a T1 interface.
A BRI-to-PRI cross-connect cannot be configured.
Analog-to-BRI/PRI cross-connect cannot be configured; the only connection for analog is analog-to-T1/E1 CAS (ds0-group).
The local-bypass command has no effect when cross-connect is configured. It is applicable only to calls that are hairpinned via POTS-to-POTS dial peers.
The DS0 group must contain only one time slot. The signaling type of the DS0 group must match that of the analog voice port.
If the channel bank feature is used for the T1 controller, the rest of the unused DS0 group cannot be used for fractional PRI signaling.
SUMMARY STEPS
1.
enable
2.
configure terminal
3.
controller {t1 | e1} slot/port
4.
ds0-group ds0-group-number timeslots timeslot-list type {e&m-delay-dial | e&m-fgd | e&m-immediate-start | e&m-wink-start | fxo-ground-start | fxo-loop-start | fxs-ground-start | fxs-loop-start}
5.
exit
6.
voice-port slot/port
7.
shutdown
8.
operation {2-wire | 4-wire}
9.
type {1 | 2 | 3 | 5}
10.
signal {loop-start | ground-start}
or
signal {wink-start | immediate | delay-dial}11.
no shutdown
12.
exit
13.
connect connection-name voice-port voice-port-number {t1 | e1} controller-number ds0-group-number
14.
end
DETAILED STEPS
Troubleshooting Tips
In some rare instances, if you have installed the VIC2-2FXO or the VIC2-4FXO and configured the voice port for groundstart signaling, you may have difficulty connecting some outgoing calls. The problem relates to the FXO groundstart voice port failing to detect a tip-ground acknowledgment, resulting in an unsuccessful call setup.
If you encounter this problem, upgrade your Cisco IOS software image to the latest version (for example, if you have Release 12.3(11)T installed, upgrade to Release 12.3(11)T2). This should fix the problem.
If this problem still occurs, you must enable the groundstart auto-tip command in the configuration of the FXO voice port. When you are placing outgoing calls, this ensures that the circuit detects a tip-ground acknowledgment from the far end and completes the connection within the time-out parameter. For information about the groundstart auto-tip command, refer to the "groundstart auto-tip" section.
For more information about this problem and more comprehensive troubleshooting steps, use the reference provided in the "Technical Assistance" section. You can search the website using keywords groundstart, analog, and fxo to obtain information on the topic described here.
Configuration Example for IP Communications Voice/Fax Network Module
This section provides a configuration example for the following:
•
Channel Bank Support: Example
Channel Bank Support: Example
This section provides an example of partial output from the show command after channel bank support has been configured:
Router# show startup-config
!voice-card 1!voice-card 2!voice-card 4!!controller T1 1/0framing esflinecode b8zsds0-group 1 timeslots 1 type e&m-wink-start!controller T1 2/0framing esflinecode b8zsds0-group 1 timeslots 1 type fxs-loop-start!controller T1 4/0framing esflinecode b8zsds0-group 1 timeslots 1 type fxo-loop-startconnect cbfxs voice-port 4/0/0 T1 4/0 1!!connect cbem voice-port 1/0/0 T1 1/0 1!!connect cbfxo voice-port 2/0/0 T1 2/0 1!!!voice-port 1/0/0description E&M portoperation 4-wiretype 2!!voice-port 2/0/0description FXO port!voice-port 4/0/0description FXS port!The following is an example of output from the show connection all command to list active connections:
Router# show connection all
ID Name Segment 1 Segment 2 State==========================================================================1 cbfxs voice-port 4/0/0 T1 4/0 01 UP2 cbem voice-port 1/0/0 T1 1/0 01 UP3 cbfxo voice-port 2/0/0 T1 2/0 01 UPAdditional References
The following sections provide references related to the IP Communications Voice/Fax Network Module feature.
Related Documents
Related Topic Document TitleHardware installation instructions for network modules
General information about voice configuration and commands
Cisco IOS Voice Command Reference, Release 12.3T
Update to information about voice configuration cards
Voice Network Module and Voice Interface Card Configuration Note
Standards
RFCs
MIBs
Technical Assistance
Command Reference
This section documents modified commands and commands commonly used with this feature. Due to the complexity of some of these commands, they may be presented here in abbreviated form. The complete platform and syntax information for these commands and all other commands used with this feature are documented in the Cisco IOS Release 12.3 Voice Configuration Library.
channel-group
To configure serial WAN on a T1 or E1 interface, use the channel-group command in controller configuration mode. To clear a channel group, use the no form of this command.
Cisco 2600 Series
channel-group channel-group-number timeslots range [speed kbps] [aim aim-slot-number]
no channel-group channel-group-number
Cisco 2611 (Cisco Signaling Link Terminal [SLT])
channel-group channel-number
no channel-group channel-number
Cisco 2600XM Series, Cisco 2691, Cisco 3631, Cisco 3660, Cisco 3725, and Cisco 3745
channel-group channel-group-number {timeslots range [speed {56 | 64}] | unframed} [aim aim-slot-number]
no channel-group [channel-group-number timeslots range]
Cisco AS5350 and Cisco AS5400 Series
channel-group channel-group-number
no channel-group channel-group-number
Cisco MC3810
channel-group channel-number timeslots range [speed kbps}]
no channel-group [channel-number timeslots range]
Syntax Description
Defaults
The T1/E1 line is connected to the Motorola MPC-860x processor serial communication controller (SCC) or network module with two voice or WAN interface card (VIC or WIC) slots and 0/1/2 FastEthernet ports DSCC4 by default on Cisco 2600 series, Cisco 2600XM, Cisco 2691, Cisco 3631, Cisco 3660, Cisco 3725, and Cisco 3745 routers.
There is no default behavior or values on the Cisco SLT (Cisco 2611).
The serial interface object encapsulation is set to HDLC on a network access server (NAS) (Cisco AS5350 and Cisco AS5400 series routers).
The default line speed is 56 kbps when a T1 controller is configured on the Cisco 2600 series, Cisco 2600XM series, Cisco 2691, Cisco 3631, Cisco 3660, Cisco 3725, Cisco 3745, and the Cisco MC3810.
The default line speed is 64 kbps when an E1 controller is configured on the Cisco 2600 series, Cisco 2600XM series, Cisco 2691, Cisco 3631, Cisco 3660, Cisco 3725, Cisco 3745, and the Cisco MC3810.
Command Modes
Controller configuration
Command History
Usage Guidelines
Use this command to direct High-Level Data Link Control (HDLC) traffic from the T1/E1 interface to the AIM-ATM-VOICE-30 DSP card. A channel group is created using Advanced Integration Module (AIM) HDLC resources when a channel-group command with the aim keyword is parsed during system initialization or when the command is entered during configuration. You must specify the aim keyword under a T1/E1 controller port to direct HDLC traffic from the T1/E1 interface to the AIM-ATM-VOICE-30 DSP card on the Cisco 2600 series, Cisco 2600XM series, Cisco 2691, Cisco 3631, Cisco 3660, Cisco 3725, and Cisco 3745.
Note
Neither the Cisco AS5400 series NAS nor the Cisco MC3810 is supported with the integrated voice and data WAN on T1/E1 interfaces using the AIM-ATM-VOICE-30 module.
If previous channel-group commands are configured with the aim keyword, subsequent channel-group commands without the aim keyword are rejected. Similarly, if a regular channel-group command is followed by another channel-group command with the aim keyword implemented, the second command is rejected on the Cisco 2600 and Cisco 2600XM.
A channel group using AIM HDLC resources is deleted only when a no channel-group command is entered.
By default, the channel-group command on a NAS sets the serial interface object encapsulation to HDLC. You must override the default by entering the encapsulation ss7 command for that serial interface object. Once you override the default, encapsulation cannot be changed again for that object. The SS7 encapsulation option is new to the Integrated Signaling Link Terminal feature and is available only for interface serial objects created by the channel-group command. The Integrated Signaling Link Terminal feature added SLT functionality on Cisco AS5350 and Cisco AS5400 platforms.
A digital SS7 link can be deleted by entering the no channel-group channel-group-number command on the associated T1/E1 controller. The link must first be stopped using the no shutdown command. It is not necessary to remove the channel ID association first.
Use the channel-group command in configurations where the router or access server must communicate with a T1 or E1 fractional data line. The channel group number may be arbitrarily assigned and must be unique for the controller. The time slot range must match the time slots assigned to the channel group. The service provider defines the time slots that comprise a channel group.
Note
Channel groups, channel-associated signaling (CAS) voice groups, and time-division multiplexing (TDM) groups all use group numbers. All group numbers configured for channel groups, CAS voice groups, and TDM groups must be unique on the local Cisco MC3810 concentrator. For example, you cannot use the same group number for a channel group and for a TDM group. Furthermore, on the Cisco MC3810, only one channel group can be configured on a controller.
The channel group number can be 0 or 1 on the Cisco SLT (Cisco 2611).
The channel-group command also applies to Voice over Frame Relay, Voice over ATM, and Voice over HDLC on the Cisco MC3810.
Examples
The following example shows basic configuration directing HDLC traffic from the T1/E1 interface to the AIM-ATM-VOICE-30 DSP card, starting in global configuration mode:
Router(config)# controller e1 1/0
Router(config-controller)# clock source internal
Router(config-controller)# channel-group 0 timeslots 1-31 aim 0The following example explicitly sets the encapsulation type to PPP to override the HDLC default:
Router# configure terminal
Router(config)# controller t1 6/0
Router(config-controller)# channel-group 2 timeslots 3 aim 0
Router(config-controller)# exit
Router(config)# interface serial 6/0:2
Router(config-if)# encapsulation ppp
Router(config-if)# ip address 12.0.0.1 255.0.0.0
Router(config-if)# no shutdown
Router(config-if)# end
The following example shows how to explicitly set the encapsulation type to SS7 to override the HDLC default using the Integrated Signaling Link Terminal feature. This example uses an 8PRI DFC card inserted into slot 7, and DS0-timeslot 3 on trunk 5 of that card is used as an SS7 link:
Router# configure terminal
Router(config)# controller t1 7/5
Router(config-controller)# channel-group 2 timeslots 3
Router(config-controller)# exit
Router(config)# interface serial 7/5:2
Router(config-if)# encapsulation ss7
Router(config-if)# channel-id 0
Router(config-if)# no shutdown
Router(config-if)# end
The following example defines three channel groups. Channel-group 0 consists of a single time slot, channel-group 8 consists of seven time slots and runs at a speed of 64 kbps per time slot, and channel-group 12 consists of two time slots.
Router(config-controller)# channel-group 0 timeslots 1
Router(config-controller)# channel-group 8 timeslots 5,7,12-15,20 speed 64
Router(config-controller)# channel-group 12 timeslots 2
The following example configures a channel group on controller T1 0 on a Cisco MC3810:
Router(config)# controller T1 0
Router(config-controller)# channel-group 10 timeslots 10 64
Note
SS7 digital F-link support for the 8PRI line card requires use of a third onboard TDM stream to route trunk DS0 messages to the onboard Media Gateway Controllers (MGCs).
Related Commands
codec complexity
To specify call density and codec complexity based on the codec standard you are using, use the codec complexity command in voice-card configuration mode. To reset the voice card to the default, use the no form of this command.
codec complexity {flex | high | medium}
no codec complexity
Syntax Description
Defaults
Medium complexity
Command Modes
Voice-card configuration
Command History
Usage Guidelines
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 DSPs. With higher codec complexity, fewer calls can be handled. Select a higher codec complexity if that is required 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.
Before codec complexity can be changed, all the DSP voice channels must be in the idle state.
Examples
The following example sets the codec complexity to high on voice card 1 in a Cisco 2600 or Cisco 3600 series router:
voice-card 1 codec complexity highRelated Commands
connect
To define connections between T1 or E1 controller ports for the channel bank feature, use the connect command in global configuration mode. To restore default values, use the no form of this command.
connect connection-name voice-port voice-port-number {t1 | e1} controller-number ds0-group-number
no connect connection-name voice-port voice-port-number {t1 | e1} controller-number ds0-group-number
Syntax Description
Defaults
There is no drop-and-insert connection between the ports.
Command Modes
Global configuration
Command History
Usage Guidelines
The connect command creates a named connect between two DS0 groups associated with voice ports on T1 or E1 interfaces where the groups have been defined by the ds0-group command.
Examples
The following example shows how to configure a channel bank connection for FXS loop-start signaling:
Router(config)# controller t1 1/0
Router(config-controller)# ds0-group 1 timeslot 0 type fxo-loop-start
Router(config-controller)# exit
Router(config)# voice-port 1/1/0
Router(config-voiceport)# signal-type fxs-loop-start
Router(config-voiceport)# exit
Router(config)# connect connection1 voice-port 1/1/0 t1 1/0 0
Related Commands
connect (drop-and-insert)
To define connections among T1 or E1 controller ports for drop-and-insert (also called TDM cross-connect), use the connect command in global configuration mode. To restore default values, use the no form of this command.
connect id {t1 | e1} slot/port1 tdm-group1 {t1 | e1} slot/port2 tdm-group2
no connect id {t1 | e1} slot/port1 tdm-group1 {t1 | e1} slot/port2 tdm-group2
Syntax Description
Defaults
There is no drop-and-insert connection between the ports.
Command Modes
Global configuration
Command History
Usage Guidelines
The connect command creates a named connect between two TDM groups associated with drop-and-insert ports on T1 or E1 interfaces where you have already defined the groups by using the tdm-group command.
Once TDM groups are created on two different physical ports, you can use the connect command to start the passage of data between the ports.
The VWIC can make a connection only if the number of time slots at the source and destination are the same. For the connection to be error-free, the two ports must be driven by the same clock source; otherwise, "slips" will occur.
Examples
The following example shows a fractional T1 terminated on port 0 using time slots 1 through 8; a fractional T1 is terminated on port 1 using time slots 2 through 12; and time slots 13 through 20 from port 0 are connected to time slots 14 through 21 on port 1 by using the connect command:
controller t1 0/0channel-group 1 timeslots 1-8 tdm-group 1 timeslots 13-20exitcontroller t1 0/1channel-group 1 timeslots 2-12 tdm-group 2 timeslot 14-21exitconnect connection1 t1 0/0 1 t1 0/1 2Related Commands
ds0-group
To specify the DS0 time slots that make up a logical voice port on a T1 or E1 controller and to specify the signaling type by which the router communicates with the PBX or public switched telephone network (PSTN), use the ds0-group command in controller configuration mode. To remove the group and signaling setting, use the no form of this command.
ds0-group ds0-group-number timeslots timeslot-list type {e&m-delay-dial | e&m-fgd | e&m-immediate-start | e&m-wink-start | fxo-ground-start | fxo-loop-start | fxs-ground-start | fxs-loop-start}
no ds0-group ds0-group-number
Syntax Description
Defaults
No DS0 group is defined.
Command Modes
Controller configuration
Command History
Usage Guidelines
The ds0-group command automatically creates a logical voice port that is numbered as follows:
slot/port:ds0-group-number
Although only one voice port is created for each group, applicable calls are routed to any channel in the group.
Examples
The following example shows ranges of T1 controller time slots configured for FXS ground-start and FXO loop-start signaling on a Cisco 2600 or 3600 series router:
T1 1/0framing esflinecode b8zsds0-group 1 timeslots 1-10 type fxs-ground-startds0-group 2 timeslots 11-24 type fxo-loop-startRelated Commands
Command Descriptioncodec
Specifies the voice coder rate of speech for a dial peer.
codec complexity
Specifies call density and codec complexity based on the codec standard you are using.
groundstart auto-tip
To configure a timing delay on an FXO groundstart voice port, use the groundstart auto-tip command in voice-port configuration mode. To disable the configured timeout, use the no form of this command.
groundstart auto-tip [delay timer]
no groundstart auto-tip [delay timer]
Syntax Description
delay
Indicates that a specific delay time will be configured.
timer
Specifies the wait time in milliseconds that the FXO groundstart voice port will wait for a tip ground acknowledgment.
Defaults
This command is disabled by default. If the command is used without the optional keyword, the default time of 200 ms is activated.
Command Modes
Voice-port configuration
Command History
Usage Guidelines
This command should only be used after you encounter call setup problems involving FXO groundstart analog voice ports. If these problems occur, first load the latest image for your Cisco IOS Release (for example, if you are running Release 12.3(11)T, you should replace this image with Release 12.3(11)T2. Upgrading the software image should eliminate the problem. If not, then use this command as a troubleshooting measure—it should be enabled in a configuration only if you encounter problems in connecting outgoing calls. After the groundstart auto-tip command is configured, the problem should not occur again.
Use the groundstart auto-tip command only for voice ports configured for FXO groundstart signaling.
The following example sets the delay wait time for tip ground acknowledgment to 250 ms:
Router# configure terminal
Router(config)# voice-port 2/0/0
Router(config-voiceport)# shutdown
Router(config-voiceport)# groundstart auto-tip delay 250
Router(config-voiceport)# no shutdown
Router(config-voiceport)# exit
Related Commands
pri-group
To specify ISDN PRI on a channelized T1 or E1 controller, use the pri-group command in controller configuration mode. To remove the ISDN PRI configuration, use the no form of this command.
pri-group [timeslots range]
no pri-group
Syntax Description
Defaults
No ISDN PRI group is configured.
Command Modes
Controller configuration
Command History
Release Modification11.0
This command was introduced.
12.2(15)ZJ
This command was integrated into Cisco IOS Release 12.2(15)ZJ.
12.3(4)T
This command was integrated into Cisco IOS Release 12.3(4)T.
Usage Guidelines
Before you enter the pri-group command, you must specify an ISDN switch type for PRI and a T1 controller.
Note
Only one PRI group can be configured on a controller.
Examples
The following example specifies ISDN PRI on T1 slot 1, port 0:
isdn switch-type primary-4esscontrollers t1 1/0framing esflinecode b8zspri-group timeslots 2-6Related Commands
tdm-group
To configure a list of time slots for creating clear channel groups (pass-through) for time-division multiplexing (TDM) cross-connect, use the tdm-group command in controller configuration mode. To delete a clear channel group, use the no form of this command.
tdm-group tdm-group-number timeslot timeslot-list [type {fxs [loop-start | ground-start] | fxo [loop-start | ground-start]}]
no tdm-group tdm-group-number timeslot timeslot-list [type {fxs [loop-start | ground-start] | fxo [loop-start | ground-start]}]
Syntax Description
Defaults
No TDM group is configured.
Command Modes
Controller configuration
Command History
Usage Guidelines
The tdm-group command allows specific time slots to switch from port 0 to port 1 and vice versa. This command is similar to the channel-group command, but it does not create a serial interface to terminate the specified channels.
Note
Channel groups, CAS voice groups, and TDM groups all use group numbers. All group numbers configured for channel groups, CAS voice groups, and TDM groups must be unique on the local router. For example, you cannot use the same group number for a channel group and for a TDM group.
Examples
The following example shows TDM group 1 being set up to include time slots 13 through 20:
tdm-group 1 timeslots 13-20The following example configures TDM group number 20 to support FXS ground-start:
tdm-group 20 timeslot 20 type fxs ground-startRelated Commands
Command Descriptionconnect
Starts passage of data between ports for cross-connect TDM.
channel-group
Configures serial WAN on a T1 or E1 interface.
Glossary
ALI—Automatic Location Identification.
ANI—Automatic Number Identification B-channel asymmetric digital subscriber line.
BSP—Buffered Serial Port.
caller ID—A central office function where a call on an analog line sends a burst of modem tones between the first and second rings to the phone; the data burst contains the phone number (and sometimes the name) of the caller.
CDR—Call Detail Record.
CID or CLID—Caller Identification (North America uses 1200 baud FSK between first and second ring burst) or calling Line ID.
codec—coder-decoder. Algorithm that compresses or decompresses the data.
D channel—Data channel in an ISDN system that contains call setup, teardown, and X.25 packet data.
DSP—digital signal processor.
DTMF—dual tone multifrequency. Analog in-band signaling (such as touch-tone dialing).
FXS—Foreign Exchange Station used to connect directly to phones, fax machines, and key systems.
FXO—ForeigN Exchange Office. An FXO interface connects to a central office. This is the interface a standard telephone offers.
FXO-M1—FXO voice/fax interface card with battery reversal detection and caller ID support for the United States, Canada, Japan, and others.
FXO-M2—FXO voice/fax interface card with battery reversal detection and caller ID support for Europe.
FXO-M3—FXO voice/fax interface card with battery reversal detection and caller ID support for Australia.
H.323—This ITU-T standard defines a set of call control, channel setup, and codec specifications for sending real-time voice and video over networks that do not offer guaranteed quality of service.
M1—A POTS interface meeting U.S. requirements with battery reversal detection and CID, and termination impedance of 600 ohms resistive.
M2—A POTS interface meeting European requirements with battery reversal detection and CID, and termination impedance of 270 ohms plus 750 ohms in parallel with 150nF.
M3—A POTS interface meeting Australian requirements with battery reversal detection and CID, and termination impedance of 220 ohms plus 820 ohms in parallel with 120nF.
MF—multifrequency.
MGCP—Media Gateway Control Protocol.
NT—Network Termination.
NT1—Network Termination point 1 in ISDN.
NT2—Network Termination point 2 in ISDN.
ONS—On Premises Service for PABXs per EIA/TIA-464.
OPS—Off Premises Service for PABXes per EIA/TIA-464.
PBX/PABX—private (automated) branch exchange.
PSAP—Public Safety Answering Point. A facility equipped and staffed to receive 911 calls.
PSTN—public switched telephone network. Standard analog telephony infrastructure.
S0(S/T)—Subscriber line designation 0 for subscriber terminals using 4-wire full-duplex interfaces containing two B channels + one D channel + monitor overhead.
SLIC—Subscriber Line Interface Circuit. An IC providing central office-like telephone interface functionality.
S/T—Interface 4-wire interface presented by an NT to TEs.
SIP—Session Initiation Protocol.
TE—terminal equipment.
VoIP—Voice over IP. Blanket term that generally notes Cisco's standards based (H.323, and so on) approach to IP voice traffic.
VIC—voice interface card. A version of WIC but with a TDM I/F.
Note
Refer to Internetworking Terms and Acronyms for terms not included in this glossary.
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