Where in Cisco UCM are codec negotiations configured for endpoints?

Cisco Unified Communications Manager negotiates the audio (and, from 12.x onward, video) codec to be used between two endpoints according to the Region-to-Region relationship in the Device Pool. Within each Region configuration you can build an “Audio (and Video) Codec Preference List,” setting an ordered list of codecs that CUCM offers during SIP/SDP or H.245 capability exchange. Because each endpoint is assigned a Device Pool/Region, the Region’s preference list governs the codec that is finally selected. No other menu (device profile, service/enterprise parameters) provides per-endpoint codec negotiation logic.

A. Device profile settings define softkey layout and phone options; they do not contain codec preference lists or influence inter-device codec negotiation.

B. Service parameters affect global behaviors (e.g., timers), but codec selection lists are not configured here.

D. Enterprise parameters hold cluster-wide defaults; they have no field for ordered codec lists used in negotiation.

1. Cisco Unified Communications Manager Administration Guide, Release 14, “Region Configuration—Audio/Video Codec Preference List” (System→Region); pages 487-489.

2. Cisco Unified Communications SRND for CUCM 12.x, Ch. 3 “Call Admission Control,” section “Regions Control Codec Selection.”

3. Cisco Press: “Deploying Cisco Unified Communications, Collaboration, and Video Services,” ISBN 9781587145748, Ch. 4, pp. 162-164 (Region-based codec preference).