03-29-2008 08:50 AM - edited 03-15-2019 09:43 AM
When a region in CUCM is configured for higher codec (say g711) does it mean that lower codec g729 also works if phone and gateways in the region accept?
Thanks..
03-29-2008 12:47 PM
No it will not. If 2 regions are configured for 711 then that's what it will use. It's not like assigning a voice class where codecs may be negotiated.
Link:
http://www.cisco.com/en/US/docs/voice_ip_comm/cucm/admin/5_0_1/ccmcfg/b02regio.html
03-29-2008 02:47 PM
actually it will work, if in the scenario there is a GW involved and you hard-code the dial-peer to G729 you can use the codec.
the region configuration determines what will be the max BW that can be used for voice and anything less than that amount if the endpoints can use the same codec works
from the doc:
The audio codec determines the type of compression and the maximum amount of bandwidth that is used per audio call.
if you're using CUCM 6 and 3rd G phones even if you set the region to use G711 and the phones can use G722 they may use it overriding the region config
HTH
javalenc
if this helps, please rate
03-29-2008 03:22 PM
I agree with J, but you can only hard code the dial-peer if you have a H323 gateway. This would not apply to MGCP.
I was unaware though about CUCM6 and 3rd G phones over-riding region configurations. What about 4 & 5?
Thanks for the tip
MC
03-29-2008 03:49 PM
I know for a fact that 5.x and 6.x have it, but i would need to double-check the support on 4.x but i think the support started with 5.x
Release Notes for Cisco Unified CallManager Release 5.1(3)
Using the G.722 Codec
http://www.cisco.com/en/US/docs/voice_ip_comm/cucm/rel_notes/5_1_3/513cmrn.html#wp192570
When enabled, the service parameter allows Cisco Unified IP Phones (such as 7971, 7970, 7941, 7961) to negotiate and use the G.722 codec when calls are within the same region.
It uses the same BW as G711 but the technology used differs on the fact G722 has a higher sampling rate which carries more info in the same BW as a G711 call, it's explained better in the link in case you want to know some more on this codec
since the codec has a better quality over the same BW as G711, if the phones are capable of using it, they will, even if you have the region to G711. if you have the region configured to a codec that uses less than 56K it won't work and then you will use the codec from the region
HTH
javalenc
if this helps, please rate
03-29-2008 05:17 PM
Excellent, Excellent information my friend. Thanks for the documentation.
MC
Discover and save your favorite ideas. Come back to expert answers, step-by-step guides, recent topics, and more.
New here? Get started with these tips. How to use Community New member guide