Protocol Negotiation

[kavadiki_Rakesh]

Hello Every one,

Could you please let me know where dose the Protocol negotiation happens between a call from A to B

Consider Phone A is on SCCP and Phone B is on SIP 

[Deepak Rawat]

There is nothing as such Protocol Negotiation. For a call to get established between two phones (no matter if they are running same protocol or different), there had to be atleast one common codec that both phones should be supporting.

For example, if Phone A supports G729, G722 and Phone B only had the capabilities of G722 and G711 then the call will be established using G722 codec . In case if there are no matching codecs between both the phones, then the need of Transcoder will arise.

Regards

Deepak

[Vivek Batra]

Hi,

If I understand your question correctly, protocol negotiation is taken care by call manager. For instance in case of Cisco, it's CUCM. So A and B both will be registered with CUCM using different protocol and it is CUCM which will translate between SCCP and SIP.

- Vivek