Contents

• Configuring SIP 181 Call is Being Forwarded Message
• Finding Feature Information
• Prerequisites for SIP 181 Call is Being Forwarded Message
• Configuring SIP 181 Call is Being Forwarded Message Globally
• Configuring SIP 181 Call is Being Forwarded Message at the Dial-Peer Level
• Configuring Mapping of SIP Provisional Response Messages Globally
• Configuring Mapping of SIP Provisional Response Messages at the Dial-Peer Level
• Feature Information for Configuring SIP 181 Call is Being Forwarded Message

Configuring SIP 181 Call is Being Forwarded Message

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You can configure support for SIP 181 Call is Being Forwarded messages either globally or on a specific dial-peer. Use the block command in voice service SIP configuration mode to globally configure Cisco IOS voice gateways and Cisco UBEs to drop specified SIP provisional response messages. To configure settings for an individual dial peer, use the voice-class sip block command in dial peer voice configuration mode. Both globally and at the dial peer level, you can also use the sdp keyword to further control when the specified SIP message is dropped based on either the absence or presence of SDP information.

Additionally, you can use commands introduced for this feature to configure a Cisco UBE, either globally or at the dial peer level, to map specific received SIP provisional response messages to a different SIP provisional response message on the outgoing SIP dial peer. To do so, use the map resp-code command in voice service SIP configuration mode for global configuration or, to configure a specific dial peer, use the voice-class sip map resp-code in dial peer voice configuration mode.

This section contains the following tasks:

• Finding Feature Information
• Prerequisites for SIP 181 Call is Being Forwarded Message
• Configuring SIP 181 Call is Being Forwarded Message Globally
• Configuring SIP 181 Call is Being Forwarded Message at the Dial-Peer Level
• Configuring Mapping of SIP Provisional Response Messages Globally
• Configuring Mapping of SIP Provisional Response Messages at the Dial-Peer Level
• Feature Information for Configuring SIP 181 Call is Being Forwarded Message

Finding Feature Information

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 SIP 181 Call is Being Forwarded Message

Cisco Unified Border Element

Cisco IOS Release 15.0(1)XA or a later release must be installed and running on your Cisco Unified Border Element.

Cisco Unified Border Element (Enterprise)

• Cisco IOS XE Release 3.1S or a later release must be installed and running on your Cisco ASR 1000 Series Router.

Configuring SIP 181 Call is Being Forwarded Message Globally

Perform this task to configure support for SIP 181 messages at a global level in SIP configuration (conf-serv-sip) mode.

SUMMARY STEPS

1.    enable


2.    configure terminal


3.    voice service voip


4.    sip


5.    block {180 | 181 | 183} [sdp {absent | present}]


6.    exit

DETAILED STEPS

	Command or Action	Purpose
Step 1	enable Example: Router> enable	Enters privileged EXEC mode, or other security level set by a system administrator. Enter your password if prompted.
Step 2	configure terminal Example: Router# configure terminal	Enters global configuration mode.
Step 3	voice service voip Example: Router(config)# voice service voip	Enters voice service VoIP configuration mode.
Step 4	sip Example: Router(conf-voi-serv)# sip	Enters SIP configuration mode.
Step 5	block {180 | 181 | 183} [sdp {absent | present}] Example: Router(conf-serv-sip)# block 181 sdp present	Configures support of SIP 181 messages globally so that messages are passed as is. The sdp keyword is optional and allows for dropping or passing of SIP 181 messages based on the presence or absence of SDP.
Step 6	exit Example: Router(conf-serv-sip)# exit	Exits the current mode.

Configuring SIP 181 Call is Being Forwarded Message at the Dial-Peer Level

Perform this task to configure support for SIP 181 messages at the dial-peer level, in dial peer voice configuration (config-dial-peer) mode.

SUMMARY STEPS

1.    enable


2.    configure terminal


3.    dial-peer voice tag voip


4.    voice-class sip block {180 | 181 | 183} [sdp {absent | present}]


5.    exit

DETAILED STEPS

	Command or Action	Purpose
Step 1	enable Example: Router> enable	Enters privileged EXEC mode, or other security level set by a system administrator. Enter your password if prompted.
Step 2	configure terminal Example: Router# configure terminal	Enters global configuration mode.
Step 3	dial-peer voice tag voip Example: Router(config)# dial-peer voice 2 voip	Enters dial peer VoIP configuration mode.
Step 4	voice-class sip block {180 | 181 | 183} [sdp {absent | present}] Example: Router(config-dial-peer)# voice-class sip block 181 sdp present	Configures support of SIP 181 messages on a specific dial peer so that messages are passed as is. The sdp keyword is optional and allows for dropping or passing of SIP 181 messages based on the presence or absence of SDP.
Step 5	exit Example: Router(config-dial-peer)# exit	Exits the current mode.

Configuring Mapping of SIP Provisional Response Messages Globally

Perform this task to configure mapping of specific received SIP provisional response messages at a global level in SIP configuration (conf-serv-sip) mode.

SUMMARY STEPS

1.    enable


2.    configure terminal


3.    voice service voip


4.    sip


5.    map resp-code 181 to 183


6.    exit

DETAILED STEPS

	Command or Action	Purpose
Step 1	enable Example: Router> enable	Enters privileged EXEC mode, or other security level set by a system administrator. Enter your password if prompted.
Step 2	configure terminal Example: Router# configure terminal	Enters global configuration mode.
Step 3	voice service voip Example: Router(config)# voice service voip	Enters voice service VoIP configuration mode.
Step 4	sip Example: Router(conf-voi-serv)# sip	Enters SIP configuration mode.
Step 5	map resp-code 181 to 183 Example: Router(conf-serv-sip)# map resp-code 181 to 183	Enables mapping globally of received SIP messages of a specified message type to a different SIP message type.
Step 6	exit Example: Router(conf-serv-sip)# exit	Exits the current mode.

Configuring Mapping of SIP Provisional Response Messages at the Dial-Peer Level

Perform this task to configure mapping of received SIP provisional response messages at the dial-peer level, in dial peer voice configuration (config-dial-peer) mode.

SUMMARY STEPS

1.    enable


2.    configure terminal


3.    dial-peer voice tag voip


4.    voice-class sip map resp-code 181 to 183


5.    exit

DETAILED STEPS

	Command or Action	Purpose
Step 1	enable Example: Router> enable	Enters privileged EXEC mode, or other security level set by a system administrator. Enter your password if prompted.
Step 2	configure terminal Example: Router# configure terminal	Enters global configuration mode.
Step 3	dial-peer voice tag voip Example: Router(config)# dial-peer voice 2 voip	Enters dial peer VoIP configuration mode.
Step 4	voice-class sip map resp-code 181 to 183 Example: Router(config-dial-peer)# voice-class sip map resp-code 181 to 183	Enables mapping of received SIP messages of a specified SIP message type on a specific dial peer to a different SIP message type.
Step 5	exit Example: Router(config-dial-peer)# exit	Exits the current mode.

Feature Information for Configuring SIP 181 Call is Being Forwarded Message

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.

Feature History Table entry for the Cisco Unified Border Element.

Table 1 Feature Information for SIP 181 Call is Being Forwarded Messages

Feature Name	Releases	Feature Information
SIP 181 Call is Being Forwarded Message	12.2(13)T	This feature allows users to configure support for SIP 181 Call is Being Forwarded messages either globally or on a specific dial-peer. This feature includes the following new or modified commands: block, map resp-code, voice-class sip block, voice-class sip map resp-code.

Feature History Table entry for the Cisco Unified Border Element (Enterprise).

Table 2 Feature Information for SIP 181 Call is Being Forwarded Messages

Feature Name	Releases	Feature Information
SIP 181 Call is Being Forwarded Message	Cisco IOS XE Release 3.1S	This feature allows users to configure support for SIP 181 Call is Being Forwarded messages either globally or on a specific dial-peer. This feature includes the following new or modified commands: block, map resp-code, voice-class sip block, voice-class sip map resp-code.