I'm new to VOIP application development. I successfully made an iphone voip app and an android voip app, and I can talk to my friends via this voip app. I have my own asterisk server set up on a linux operating system.
In making the phone voip app, I used whichever codec was native to the sip library I integrated with (in this case, it was linphone sip library). Now I'm interested in figuring out which codec is being used. After some debugging, my android app says I'm using the PCMU codec. This is very unusual because in my asterisk server sip.conf file, I only allow ulaw and gsm codecs.
So my question is, how come my voip app works perfectly when there's a mismatch in codecs between my phone app (using PCMU) and my asterisk server (allowing only ulaw and gsm)? I'd expect my app to break because of this codec mis-match.
