Quick question :- Dial-peer & Voice class codec

[Manish Prasad]

Hi ,

On CUBE if Inbound dial-peer has codec class set and the outbound dial-peer (to ITSP) has nothing defined ( no voice class codec , no codec ) and my transcoders are up and running and Early offer is configured on CUBE.

My question is the how outbound INVITE to ITSP will pull its codec offer details ? It just relay what it has received from Inbound INVITE ? Or call will fail ?

Thanks

Manish

[Chris Deren]

It depends on if you are using EO or DO, if EO the codec capability is sent in the SDP of the initial INVITE, if codec is not defined on the dial-peer default G729 is used. In DO no codec is sent initially and the receiving end responds with codec capabilities to which both sides will agree.

Chris

[Manish Prasad]

Thank you Chris and Suresh.

As Chris pointed out the default behavior of a dial-peer is G729 but when DSP/Resource is there , it should had initiated an INVITE request but i didn't .(even i got the same 503 error when i tested).

Thanks

Manish

[Suresh Subramanian · Accepted solution]

Hi Manish,

If you configure 'pass-thru content sdp', then the codecs received on the inbould leg would be passed to outbound leg though you don't configure voice class codec/codec commands.

But if you don't have 'pass-thru' configured it, then No invite message will be sent out and the call would fail with Cause Value=47 & 503 Service Unavailable.

PS: it is the tested behaviour from my side.

//Suresh
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