The DTMF Events through SIP Signaling feature provides the following:
DTMF event notification for SIP messages.
Capability of receiving hookflash event notification through the SIP NOTIFY method.
Third-party call control, or other signaling mechanisms, to provide enhanced services, such as calling card and messaging services.
Communication with the application outside of the media connection.
The DTMF Events through SIP Signaling feature allows telephone event notifications to be sent through SIP NOTIFY messages, using the SIP SUBSCRIBE/NOTIFY method as defined in the Internet Engineering Task Force (IETF) draft, SIP-Specific Event Notification.
The feature also supports sending DTMF notifications based on the IETF draft: Signaled Telephony Events in the Session Initiation Protocol (SIP) (draft-mahy-sip-signaled-digits-01.txt).
Your software release may not support all the features documented in this module. For the latest caveats and feature information, see
Bug Search Tool and the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the feature information table at the end of this module.
Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to
www.cisco.com/go/cfn. An account on Cisco.com is not required.
Prerequisites for DTMF Events through SIP Signaling
Cisco Unified Border Element
Cisco IOS Release 12.2(11)T or a later release must be installed and running on your Cisco Unified Border Element.
Cisco Unified Border Element (Enterprise)
Cisco IOS XE Release 2.5 or a later release must be installed and running on your Cisco ASR 1000 Series Router.
Restrictions for DTMF Events through SIP Signaling
The DTMF Events through SIP Signaling feature adds support for sending telephone-event notifications via SIP NOTIFY messages from a SIP gateway. The events for which notifications are sent out are DTMF events from the local Plain Old Telephone Service (POTS) interface on the gateway. Notifications are not sent for DTMF events received in the Real-Time Transport Protocol (RTP) stream from the recipient user agent.
Configuring DTMF Events through SIP Signaling
To configure the DTMF Events through SIP Signaling feature, perform the following steps.
SUMMARY STEPS
1.enable
2.configureterminal
3.sip-ua
4.timersnotifynumber
5.retrynotifynumber
6.exit
DETAILED STEPS
Command or Action
Purpose
Step 1
enable
Example:
Device> enable
Enters privileged EXEC mode or any other security level set by a system administrator.
Enter your password if prompted.
Step 2
configureterminal
Example:
Device# configure terminal
Enters global configuration mode.
Step 3
sip-ua
Example:
Device(config)# sip-ua
Enters SIP user-agent configuration mode.
Step 4
timersnotifynumber
Example:
Device(config-sip-ua)# timers notify 100
Sets the amount of time that the user agent waits before retransmitting the Notify message. The argument is as follows:
number--Time, in milliseconds, to wait before retransmitting. Range: 100 to 1000. Default: 500.
Step 5
retrynotifynumber
Example:
Device(config-sip-ua)# retry notify 6
Sets the number of times that the Notify message is retransmitted to the user agent that initiated the transfer or Refer request. The argument is as follows:
number--Number of retries. Range: 1 to 10. Default: 10.
Step 6
exit
Example:
Device(config-sip-ua)# exit
Exits the current mode.
Verifying SIP DTMF Support
To verify SIP DTMF support, perform the following steps as appropriate (commands are listed in alphabetical order).
SUMMARY STEPS
1.showrunning-config
2.showsip-uaretry
3.showsip-uastatistics
4.showsip-uastatus
5.showsip-uatimers
6.showvoiprtpconnections
7.showsip-uacalls
DETAILED STEPS
Step 1
showrunning-config
Use this command to show dial-peer configurations.
The following sample output shows that the
dtmf-relaysip-notify command is configured in dial peer 123:
Use this command to display status for the SIP user agent.
Example:
Device# show sip-ua status
SIP User Agent Status
SIP User Agent for UDP : ENABLED
SIP User Agent for TCP : ENABLED
SIP User Agent bind status(signaling): DISABLED
SIP User Agent bind status(media): DISABLED
SIP max-forwards : 6
SIP DNS SRV version: 2 (rfc 2782)
SDP application configuration:
Version line (v=) required
Owner line (o=) required
Session name line (s=) required
Timespec line (t=) required
Media supported: audio image
Network types supported: IN
Address types supported: IP4
Transport types supported: RTP/AVP udptl
The following sample output shows that the time interval between consecutive NOTIFY messages for a telephone event is the default of 2000 ms:
Example:
Device# show sip-ua status
SIP User Agent Status
SIP User Agent for UDP : ENABLED
SIP User Agent for TCP : ENABLED
SIP User Agent bind status(signaling): DISABLED
SIP User Agent bind status(media): DISABLED
SIP early-media for 180 responses with SDP: ENABLED
SIP max-forwards : 6
SIP DNS SRV version: 2 (rfc 2782)
NAT Settings for the SIP-UA
Role in SDP: NONE
Check media source packets: DISABLED
Maximum duration for a telephone-event in NOTIFYs: 2000 ms
SIP support for ISDN SUSPEND/RESUME: ENABLED
Redirection (3xx) message handling: ENABLED
SDP application configuration:
Version line (v=) required
Owner line (o=) required
Timespec line (t=) required
Media supported: audio image
Network types supported: IN
Address types supported: IP4
Transport types supported: RTP/AVP udptl
The following sample output shows configuration of the SIP INFO Method for DTMF Tone Generation feature:
Example:
Device# show sip-ua status
SIP User Agent Status
SIP User Agent for UDP : ENABLED
SIP User Agent for TCP : ENABLED
SIP User Agent bind status(signaling): DISABLED
SIP User Agent bind status(media): DISABLED
SIP max-forwards : 6
SIP DNS SRV version: 2 (rfc 2782)
SDP application configuration:
Version line (v=) required
Owner line (o=) required
Session name line (s=) required
Timespec line (t=) required
Media supported: audio image
Network types supported: IN
Address types supported: IP4
Transport types supported: RTP/AVP udptl
Step 5
showsip-uatimers
Use this command to display the current settings for SIP user-agent timers.
Use this command to show local and remote Calling ID and IP address and port information.
Step 7
showsip-uacalls
Use this command to ensure the DTMF method is SIP-KPML.
The following sample output shows that the DTMF method isSIP-KPML.
Example:
Device# show sip-ua calls
SIP UAC CALL INFO
Call 1
SIP Call ID : 57633F68-2BE011D6-8013D46B-B4F9B5F6@172.18.193.251
State of the call : STATE_ACTIVE (7)
Substate of the call : SUBSTATE_NONE (0)
Calling Number :
Called Number : 8888
Bit Flags : 0xD44018 0x100 0x0
CC Call ID : 6
Source IP Address (Sig ): 192.0.2.1
Destn SIP Req Addr:Port : 192.0.2.2:5060
Destn SIP Resp Addr:Port: 192.0.2.3:5060
Destination Name : 192.0.2.4.250
Number of Media Streams : 1
Number of Active Streams: 1
RTP Fork Object : 0x0
Media Mode : flow-through
Media Stream 1
State of the stream : STREAM_ACTIVE
Stream Call ID : 6
Stream Type : voice-only (0)
Negotiated Codec : g711ulaw (160 bytes)
Codec Payload Type : 0
Negotiated Dtmf-relay : sip-kpml
Dtmf-relay Payload Type : 0
Media Source IP Addr:Port: 192.0.2.5:17576
Media Dest IP Addr:Port : 192.0.2.6:17468
Orig Media Dest IP Addr:Port : 0.0.0.0:0
Number of SIP User Agent Client(UAC) calls: 1
SIP UAS CALL INFO
Number of SIP User Agent Server(UAS) calls: 0
Troubleshooting Tips
To enable debugging for RTP named-event packets, use the debugvoiprtp command.
To enable KPML debugs, use the debugkpml command.
To enable SIP debugs, use the debugccsip command.
Collect debugs while the call is being established and during digit presses.
If an established call is not sending digits through KPML, use the showsip-uacalls command to ensure SIP-KPML is included in the negotiation process.
Feature Information for DTMF Events through SIP Signaling
The following table provides release information about the feature or features described in this module. This table lists only the software release that introduced support for a given feature in a given software release train. Unless noted otherwise, subsequent releases of that software release train also support that feature.
Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to
www.cisco.com/go/cfn. An account on Cisco.com is not required.
Table 1 Feature Information for Configuring DTMF Events through SIP Signaling
Feedback