Table Of Contents

Configuring Support for SIP 181 Call is Being Forwarded Message

Prerequisites

Configuring Support for SIP 181 "Call is Being Forwarded" Message Globally

Configuring Support for 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

Configuring Support for SIP 181 Call is Being Forwarded Message

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:

•Configuring Support for SIP 181 "Call is Being Forwarded" Message Globally

•Configuring Support for 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

Prerequisites

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 Support for 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 Support for 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.