-
Cisco IOS ISDN Voice Configuration Guide
-
ISDN Features Roadmap
-
Overview of ISDN Voice Interfaces
-
Basic ISDN Voice-Interface Configuration
-
Expanded Scope for Cause-Code-Initiated Call-Establishment Retries
-
Clear-Channel T3/E3 with Integrated CSU/DSU
-
High-Density Analog (FXS/DID/FXO) and Digital (BRI) Extension Module for Voice/Fax (EVM-HD)
-
Integrated Data and Voice Services for ISDN PRI Interfaces on Multiservice Access Routers
-
Integrated Voice and Data WAN on T1/E1 Interfaces
-
ISDN GTD for Setup Message
-
NFAS with D-Channel Backup
-
PRI Backhaul and IUA Support Using SCTP
-
QSIG Support for Tcl IVR 2.0
-
Implementing T1 CAS for VoIP
-
Implementing FCCS (NEC Fusion)
-
Digital J1 Voice Interface Card
-
Table Of Contents
Prerequisites for Configuring T1 CAS
Restrictions for Configuring T1 CAS
Information About T1 CAS for VoIP
E&M and Ground Start/FXS Protocols
How to Configure T1 CAS for VoIP
Configuring T1 CAS for Use with VoIP
Verifying and Troubleshooting a T1 CAS Configuration
Configuration Example for T1 CAS for VoIP
Implementing T1 CAS for VoIP
This chapter describes how to implement the T1 Channel-Associated Signaling (CAS) for VoIP feature. This feature adds support for T1 CAS and E1 R2 signaling with the voice feature card (VFC).
The T1 CAS interface is used for connection to both a private PBX and the PSTN. This feature is required by North American enterprise customers and service providers. For most enterprise customers, T1 CAS is the only type of line they use from the PSTN; E&M may be the only option for connecting to their PBX.
12.1(5)XM
This feature was introduced on the Cisco AS5800.
12.2(2)XB1
This feature was implemented on the Cisco AS5850.
12.2(11)T
This feature was integrated into this release.
Feature History for T1 CAS for VoIP
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.
Note
For more information about related Cisco IOS voice features, see the following:
•
•
For a list of references cited in this chapter, see the "Additional References" section.
Contents
•
•
•
•
•
Prerequisites for Configuring T1 CAS
•
Restrictions for Configuring T1 CAS
Restrictions are described in the Restrictions for Configuring ISDN Voice Interfaces, page 4. In addition, the following applies.
Internet service providers can provide switched 56-kbps access to their customers with this feature. The subset of T1 CAS (robbed-bit) supported features is as follows:
•
–
–
–
–
–
•
–
–
Note
–
–
Note
•
–
•
–
–
Information About T1 CAS for VoIP
Note
To implement this feature, you should understand the following concepts:
•
CAS Basics
CAS is the transmission of signaling information within the voice channel. In addition to receiving and placing calls, CAS also processes the receipt of DNIS and ANI information, which is used to support authentication and other functions.
Various types of CAS are available in the T1 world. The most common forms are loop-start, ground-start, Equal Access North American (EANA), and E&M.
The biggest disadvantage of CAS is its use of user bandwidth to perform signaling functions. CAS is often referred to as robbed-bit-signaling because user bandwidth is "robbed" by the network for other purposes.
Service-provider application for T1 CAS includes connectivity to the public network using T1 CAS from the Cisco router to the end-office switch. In this configuration, the router captures dialed-number or called-party-number information and passes it to the upper-level applications for IVR script selection, modem pooling, and other applications. Service providers also require access to ANI for user identification, billing account number, and, in the future, more complicated call routing.
Service providers who implement VoIP include traditional voice carriers, new voice and data carriers, and existing internet service providers. Some of these service providers might use subscriber-side lines for VoIP connectivity to the PSTN; others use tandem-type service-provider connections.
New CAS functionality for VoIP includes all CAS and E1/R2 signaling already supported for supported Cisco platforms in data applications, with the addition of dialed-number and calling-party-number capture whenever available.
E&M and Ground Start/FXS Protocols
This feature supports the following T1 CAS systems for VoIP applications:
•
–
In the original Wink Start protocol, the terminating side responds to an off-hook from the originating side with a short wink (transition from on-hook to off-hook and back again). This wink indicates that the terminating side is ready to receive addressing digits. After receiving digits, the terminating side goes off-hook for the duration of the call. The originating side maintains off-hook for the duration of the call.
–
In Feature Group D Wink Start with Wink Acknowledge Protocol, the terminating side responds to an off-hook from the originating side with a short wink just as in the original Wink Start. After receiving digits, the terminating side provides another wink (called an acknowledgment wink) to indicate that the terminating side has received the digits. The terminating side goes off-hook to indicate connection when the ultimate called endpoint has answered. The originating side maintains off-hook for the duration of the call.
–
In the Immediate Start Protocol, the originating side does not wait for a wink before sending addressing digits. After receiving digits, the terminating side goes off-hook for the duration of the call. The originating side maintains off-hook for the duration of the call.
•
How to Configure T1 CAS for VoIP
This section contains the following procedures:
•
•
Configuring T1 CAS for Use with VoIP
To configure T1 CAS for use with VoIP, perform the following steps.
Note
SUMMARY STEPS
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
DETAILED STEPS
Step 1
enable
Example:Router> enable
Enters privileged EXEC mode. Enter your password when prompted.
Step 2
configure terminal
Example:Router# configure terminal
Enters global configuration mode.
Step 3
controller {t1 | e1} slot/port
Example:Router(config)# controller t1 1/0/0
Enters controller configuration mode for the specified slot/port. The controller ports are labeled RI and E1/PRI cards.
Step 4
framing type
Example:Router(config-control)# framing esf
Enters your telco framing type.
Step 5
linecode type
Example:Router(config-control)# linecode b8zs
Enters your telco line code type.
Step 6
ds0-group group-number timeslots range type type {dtmf | mf} {ani | dnis | ani-dnis}
Example:Router(config-control)# ds0-group 1 timeslots 1-24 type e&m-fgb
Configures all channels for E&M, FXS, and SAS analog signaling. T1 range: 1 to 24. E1 range: 1to 31.
Some of the valid signaling types and keyword combinations are as follows:
•
–
–
•
–
–
•
–
Note
Step 7
Repeat steps 4 to 6 for each additional controller (there are 12). Be sure to increment the controller number and ds0-group number.
—
Step 8
dial-peer voice tag type
destination-pattern
port
prefix
Example:Router(config-control)# dial-peer voice 3070 pots
destination-pattern 30...
port 1/0/0:D
prefix 30
Enters dial-peer configuration mode and configures a POTS peer destination pattern.
Step 9
dial-peer voice tag type
incoming called-number
destination-pattern
direct-inward-dial
port
prefix
Example:Router(config-control)# dial-peer voice 21 pots
incoming called-number 11...
destination-pattern 40...
direct-inward-dial
port 12/0:2:0
prefix 21
Specifies, for each POTS peer, the following: incoming called number, destination pattern, and direct inward dial.
Step 10
Repeat steps 8 and 9 for each dial peer.
—
Step 11
exit
Example:Router(config-control)# exit
Exits the current mode.
Note
Verifying and Troubleshooting a T1 CAS Configuration
To verify and troubleshoot a T1 CAS configuration, perform the following steps (listed alphabetically).
SUMMARY STEPS
1.
1.
2.
3.
DETAILED STEPS
Step 1
Use the debug cas command to identify and troubleshoot call connection problems on a T1/E1 interface. With this command, you can trace the complete sequence of incoming and outgoing calls.
Examples
The following shows an example session to enable debugging CAS and generate troubleshooting output:
Router# show debugRouter# debug cas slot 1 port 0CAS debugging is onRouter#debug-cas is on at slot(1) dsx1(0)Router# show debugCAS debugging is onThe following example shows output for the first outgoing call:
Router# p 1.1.1.2Type escape sequence to abort.Sending 5, 100-byte ICMP Echos to 1.1.1.2, timeout is 2 seconds:*Mar 2 00:17:45: dsx1_alloc_cas_channel: channel 0 dsx1_timeslot1(0/0): TX SEIZURE (ABCD=0001)(0/0): RX SEIZURE_ACK (ABCD=1101)(0/1):RX_IDLE (ABCD=1001)(0/2): RX_IDLE (ABCD=1001)(0/3): RX_IDLE(ABCD=1001)(0/4): RX_IDLE (ABCD=1001)(0/5): RX_IDLE (ABCD=1001)(0/6):RX_IDLE (ABCD=1001)(0/7): RX_IDLE (ABCD=1001)(0/8): RX_IDLE(ABCD=1001)(0/9): RX_IDLE (ABCD=1001)(0/10): RX_IDLE (ABCD=1001)(0/11):RX_IDLE (ABCD=1001)(0/12): RX_IDLE (ABCD=1001)(0/13): RX_IDLE(ABCD=1001)(0/14): RX_IDLE (ABCD=1001)(0/16): RX_IDLE (ABCD=1001)(0/17):RX_IDLE (ABCD=1001)(0/18): RX_IDLE (ABCD=1001)(0/19): RX_IDLE(ABCD=1001)(0/20): RX_IDLE (ABCD=1001)(0/21): RX_IDLE(ABCD=1001).(0/22): RX_IDLE (ABCD=1001)(0/23): RX_IDLE(ABCD=1001)(0/24): RX_IDLE (ABCD=1001)(0/25): RX_IDLE (ABCD=1001)(0/26):RX_IDLE (ABCD=1001)(0/27): RX_IDLE (ABCD=1001)(0/28): RX_IDLE(ABCD=1001)(0/29): RX_IDLE (ABCD=1001)(0/30): RX_IDLE(ABCD=1001)...(0/0): RX ANSWERED (ABCD=0101).Success rate is 0 percent (0/5)Router#*Mar 2 00:18:13.333: %LINK-3-UPDOWN: Interface Async94, changed state to up*Mar 2 00:18:13.333: %DIALER-6-BIND: Interface As94 bound to profile Di1*Mar 2 00:18:14.577: %LINEPROTO-5-UPDOWN: Line protocol on Interface Async94, changedstate to upRouter# p 1.1.1.2Type escape sequence to abort.Sending 5, 100-byte ICMP Echos to 1.1.1.2, timeout is 2 seconds:!!!!!Success rate is 100 percent (5/5), round-trip min/avg/max = 160/180/236 msThe following example shows that the call is cleared on the router:
Router# clear int dialer 1Router#(0/0): TX IDLE (ABCD=1001)(0/0): RX IDLE (ABCD=1001)*Mar 2 00:18:28.617: %LINK-5-CHANGED: Interface Async94, changed state to reset*Mar 2 00:18:28.617: %DIALER-6-UNBIND: Interface As94 unbound from profile Di1*Mar 2 00:18:29.617: %LINEPROTO-5-UPDOWN: Line protocol on Interface Async94, changedstate to downet2-c3745-1#*Mar 2 00:18:33.617: %LINK-3-UPDOWN: Interface Async94, changed state to downThe following example shows a subsequent outbound CAS call:
Router# p 1.1.1.2Type escape sequence to abort.Sending 5, 100-byte ICMP Echos to 1.1.1.2, timeout is 2 seconds:*Mar 2 00:18:40: dsx1_alloc_cas_channel: channel 5 dsx1_timeslot6(0/5): TX SEIZURE (ABCD=0001)(0/5): RX SEIZURE_ACK(ABCD=1101)....(0/5): RX ANSWERED (ABCD=0101).Success rate is 0 percent (0/5)Router#*Mar 2 00:19:08.841: %LINK-3-UPDOWN: Interface Async93, changed state to up*Mar 2 00:19:08.841: %DIALER-6-BIND: Interface As93 bound to profile Di1*Mar 2 00:19:10.033: %LINEPROTO-5-UPDOWN: Line protocol on Interface Async93, changedstate to upRouter# p 1.1.1.2Type escape sequence to abort.Sending 5, 100-byte ICMP Echos to 1.1.1.2, timeout is 2 seconds:!!!!!Success rate is 100 percent (5/5), round-trip min/avg/max = 160/167/176msThe following example shows the call cleared by the switch:
Router#(0/5): TX IDLE (ABCD=1001)(0/5): RX IDLE (ABCD=1001)*Mar 2 00:19:26.249: %LINK-5-CHANGED: Interface Async93, changed state to reset*Mar 2 00:19:26.249: %DIALER-6-UNBIND: Interface As93 unbound from profile Di1*Mar 2 00:19:27.249: %LINEPROTO-5-UPDOWN: Line protocol on Interface Async93, changedstate to downRouter#*Mar 2 00:19:31.249: %LINK-3-UPDOWN: Interface Async93, changed state to downThe following example shows an incoming CAS call:
Router#(0/0): RX SEIZURE (ABCD=0001)*Mar 2 00:22:40: dsx1_alloc_cas_channel: channel 0 dsx1_timeslot1(0/0): TX SEIZURE_ACK (ABCD=1101)(0/0): TX ANSWERED (ABCD=0101)Router#*Mar 2 00:23:06.249: %LINK-3-UPDOWN: Interface Async83, changed state to up*Mar 2 00:23:06.249: %DIALER-6-BIND: Interface As83 bound to profile Di1*Mar 2 00:23:07.653: %LINEPROTO-5-UPDOWN: Line protocol on Interface Async83, changedstate to upStep 2
Use this command to display the controller and alarm status for the specified dial shelf/slot/port. Configuration is successful if the controller reports being up and no error are reported.
Router# show controllers t1 1/0/0T1 1/0/0 is up.Applique type is Channelized T1Cablelength is long gain36 0dbNo alarms detected.alarm-trigger is not setFraming is ESF, Line Code is B8ZS, Clock Source is Line.Data in current interval (180 seconds elapsed):0 Line Code Violations, 0 Path Code Violations0 Slip Secs, 0 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins0 Errored Secs, 0 Bursty Err Secs, 0 Severely Err Secs, 0 Unavail SecsStep 3
Use this command to display the status of all ISDN interfaces, including active layers, timer information, and switch-type settings.
Step 4
Use this command to display the basic router configuration.
Step 5
To display configuration information about a specific voice port, use the show voice port command in privileged EXEC mode. Command syntax and options vary according to platform and configuration.
Configuration Example for T1 CAS for VoIP
The sample configuration is only intended as an example of how to use the commands to configure T1 CAS. It is not an example of a complete configuration for setting up the entire signaling for a telco network.
Figure 17 T1 CAS for VoIP: Network Topology
Router# show running-configversion 12.1service timestamps debug datetime msec localtime show-timezoneservice timestamps log datetime msec localtime show-timezoneservice password-encryption!hostname travis-nas-01!aaa new-modelaaa authentication login default localaaa authentication login NO_AUTHENT noneaaa authorization exec default local if-authenticatedaaa authorization exec NO_AUTHOR noneaaa authorization commands 15 default local if-authenticatedaaa authorization commands 15 NO_AUTHOR noneaaa accounting exec default start-stop group tacacs+aaa accounting exec NO_ACCOUNT noneaaa accounting commands 15 default stop-only group tacacs+aaa accounting commands 15 NO_ACCOUNT noneenable secret 5 $1$LsoW$K/qBH9Ih2WstUxvazDgmY/!username admin privilege 15 password 7 06455E365E471D1C17username gmcmilla password 7 071824404D06140044username krist privilege 15 password 7 0832454D01181118!call rsvp-syncshelf-id 0 router-shelfshelf-id 1 dial-shelf!resource-pool disable!modem-pool Defaultpool-range 1/2/0-1/2/143,1/3/0-1/3/143!modem-pool accounts!modem-pool accounts1!modem-pool accounts2!clock timezone CST -6clock summer-time CST recurring!ip subnet-zeroip domain-name cisco.comip name-server 172.22.53.210ip name-server 171.69.2.133ip name-server 171.69.2.132ip name-server 171.69.11.48!isdn switch-type primary-5ess!controller T1 1/0/0framing esflinecode b8zsds0-group 1 timeslots 1-24 type e&m-fgb!controller T1 1/0/1framing esflinecode b8zsds0-group 1 timeslots 1-24 type e&m-fgb!controller T1 1/0/2framing esflinecode b8zsds0-group 1 timeslots 1-24 type e&m-fgb!controller T1 1/0/3framing esflinecode b8zsds0-group 0 timeslots 1-24 type e&m-fgb dtmf dnis!controller T1 1/0/4Additional References
General ISDN References
•
•
•
