g729 annexb-all
To configure Cisco IOS Session Initiation Protocol (SIP) gateway to treat the G.729br8 codec as superset of G.729r8 and G.729br8 codecs to interoperate with the Cisco Unified Communications Manager, use the g729 annexb-all command in voice service SIP configuration mode or voice class tenant configuration mode. To return to the default global setting for the gateway, where G.729br8 codec represents only the G.729br8 codec, use the no form of this command.
g729 annexb-all system
no g729 annexb-all system
Syntax Description
annexb-all |
Specifies that the G.729br8 codec is treated as a superset of G.729r8 and G.729br8 codecs to communicate with Cisco Unified Communications Manager. |
system |
Specifies that the codec use the global sip-ua value. This keyword is available only for the tenant mode to allow it to fallback to the global configurations |
Command Default
G.729br8 codec is not viewed as superset of G.729r8 and G.729br8 codecs.
Command Modes
Voice service SIP configuration (conf-serv-sip)
Voice class tenant configuration (config-class)
Command History
Release |
Modification |
---|---|
12.4(15)XZ |
This command was introduced. |
12.4(20)T |
This command was integrated into Cisco IOS Release 12.4(20)T. |
15.6(2)T and IOS XE Denali 16.3.1 |
This command was modified to include the keyword: system . |
Cisco IOS XE Amsterdam 17.2.1r |
Introduced support for YANG models. |
Usage Guidelines
There are four variations of the G.729 coder-decoder (codec), which fall into two categories:
High Complexity
-
G.729 (g729r8)--a high complexity algorithm codec on which all other G.729 codec variations are based.
-
G.729 Annex-B (g729br8 or G.729B)--a variation of the G.729 codec that allows the DSP to detect and measure voice activity and convey suppressed noise levels for re-creation at the other end. Additionally, the Annex-B codec includes Internet Engineering Task Force (IETF) voice activity detection (VAD) and comfort noise generation (CNG) functionality.
Medium Complexity
-
G.729 Annex-A (g729ar8 or G.729A)--a variation of the G.729 codec that sacrifices some voice quality to lessen the load on the DSP. All platforms that support G.729 also support G.729A.
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G.729A Annex-B (g729abr8 or G.729AB)--a variation of the G.729 Annex-B codec that, like G.729B, sacrifices voice quality to lessen the load on the DSP. Additionally, the G.729AB codec also includes IETF VAD and CNG functionality.
The VAD and CNG functionality is what causes the instability during communication attempts between two DSPs where one DSP is configured with Annex-B (G.729B or G.729AB) and the other without (G.729 or G.729A). All other combinations interoperate. To configure a Cisco IOS SIP gateway for interoperation with Cisco Unified Communications Manager (formerly known as the Cisco CallManager, or CCM), use the g729-annexb-all command in voice service SIP configuration mode to allow connection of calls between two DSPs with incompatible G.729 codecs. Use the voice-class sip g729 annexb-all command in dial peer voice configuration mode to configure G.729 codec interoperation settings for a dial peer that override global settings for the Cisco IOS SIP gateway.
Examples
The following example configures a Cisco IOS SIP gateway (globally) to be able to connect calls between otherwise incompatible G.729 codecs:
Router> enable
Router# configure terminal
Router(config)# voice service voip
Router(conf-voi-serv)# sip
Router(conf-serv-sip)# g729 annexb-all
The following example configures a Cisco IOS SIP gateway (globally) to be able to connect calls between otherwise incompatible G.729 codecs in the voice class tenant configuration mode:
Router(config-class)# g729 annexb-all system