ability to change codec being used?

[cs512tr]

hi there, just a quick one, i have been looking around and wondering is there a way of selection or even adding the codec being used in call?

currently i believe its G711a/u ?

snmp monitoring of m router shows 20KB/sec of traffic for 1 active call. As i am on 512/128K connection this tends to get chewed up with 1 / 2 active calls.

any ideas would be greatly appreciated

Cheers
Carl

 

[Borsoock]

Hi
3CX presently support also GSM codec . Check if your SIP client support this codec and set as prefered.

Thanks

Marcin

 

[cs512tr]

thanks for that!
so in general its 'configured' as such through the client-phone?

ta

Carl

 

[SY]

VoIP provider connection has configuration option to choose priority and set of codecs. It is used only to initialize outgoing call to that VoIP provider. For incoming call, currently, codec set is build basing on offer from remote party. It is done to eliminate possibility of asymmetric RTP streams and provide more reliable codec negotiations.

Note:
1. remote party can prefer other codec then you expect
2. PBX support only following codecs: G711(PCMA,PCMU), GSM, SPEEX and iLBC
3. PBX is not a simple VoIP client. (just a joke )

Regards,
Stepan

 

[Anonymous]

hi there, just a quick one, i have been looking around and wondering is there a way of selection or even adding the codec being used in call?

currently i believe its G711a/u ?

snmp monitoring of m router shows 20KB/sec of traffic for 1 active call. As i am on 512/128K connection this tends to get chewed up with 1 / 2 active calls.

any ideas would be greatly appreciated

Cheers
Carl

Yep 20KB not 20kbs i assume? With G711 you need 128kbps altleast in each direction, the good thing about G711 is that it does not need much processing power and the quality is pretty good.

I would like G729 but that is licensed so I do not see it happening anytime soon, to be available in 3CX

GSM on the other hand uses only 13kbps bandwidth compared to 64 for G.711.