On Tue, Dec 06, 2011 at 08:57:58AM +0100, Tobias Engel wrote:
Hi,
does anybody know when the exact moment in a call is, when the NanoBTS starts forwarding audio from a MS to OpenBSC?
I guess as soon as 1) a RTP stream is configured, and 2) there are actual audio speech frames received from the phone
Each frame on the TCH can be either audio or FACCH, this is differentiated in L1 by the use of the stealing flags. So as long as the phone is sending FACCH frames, they go to the LAPDm implementation in the BTS. Once it sends voice frames, they go to the RTP socket.
The RSL CHANNEL MODE (speech) might also have an influence on it.
Or could it be that the BTS waits for the "Connect" message from the MS?
The BTS doesn't have anythin to do with call control.