Important Characteristics for Enabling LATM on Cisco Unified Border Element Router

AB.

LATM (Low-latency Audio Transport Protocol) is a codec used for real-time audio communication over IP networks. When enabling LATM on the Cisco Unified Border Element (CUBE) router, there are several characteristics that a video engineer should be aware of.

A. Dual-tone multifrequency (DTMF) interworking with LATM codec is not supported: DTMF is a method used for telephone signaling, and it is not supported with LATM codec. Therefore, if a device is using DTMF signaling, it may not be able to communicate with LATM enabled devices.

B. Codec transcoding between LATM and other codecs is not supported: The CUBE router can act as a codec translator, but LATM codec transcoding is not supported. Therefore, if the endpoint device is using a codec other than LATM, the CUBE router will not be able to transcode the codec to LATM.

C. SIP UPDATE message outlined in RFC 3311 is not supported: SIP (Session Initiation Protocol) is a signaling protocol used for initiating, maintaining, and terminating real-time sessions that involve video, voice, messaging, and other communications applications and services between two or more endpoints on IP networks. RFC 3311 defines SIP UPDATE messages used to modify a session's properties during the session. The CUBE router may not support SIP UPDATE messages when LATM codec is enabled.

D. Box-to-Box high availability support feature is not supported: The Box-to-Box high availability support feature is used to provide redundancy in case of a hardware failure on the CUBE router. However, this feature may not be supported when LATM codec is enabled.

E. Configure LATM under a voice class or dial peer is not supported: Voice class and dial peers are used to configure call routing on the CUBE router. However, configuring LATM codec under a voice class or dial peer may not be supported.

F. Basic calls using flow-around or flow-through is not supported: Flow-around and flow-through are call routing options used on the CUBE router. However, basic calls may not be supported when LATM codec is enabled using these options.

In summary, when enabling LATM codec on the CUBE router, the video engineer should be aware that DTMF interworking, codec transcoding, SIP UPDATE messages, Box-to-Box high availability support, configuring LATM under a voice class or dial peer, and basic calls using flow-around or flow-through may not be supported.