Incorrect offer-answer model

In a case where User A supports only Codec 0 (PCMU), tries to establish call by 
offering the following SDP -
m=audio 6000 RTP/AVP 0 101
a=rtpmap:0 PCMU/8000
a=rtpmap:101 telephone-event/8000
a=fmtp:101 0-16
The DUT responds with the following incorrect answer violating basic 
Offer-Answer model (RFC 3262) and the impact is that no voice path was actually 
established -
a=tcap:1 RTP/AVPF
m=audio 50224 RTP/AVP 8 0 112 111 3 101
a=ptime:20
a=silenceSupp:off - - - -
a=rtpmap:8 PCMA/8000/1
a=rtpmap:0 PCMU/8000/1
a=rtpmap:112 AMR/8000/1
a=imageattr:112 octet-align=1
a=fmtp:112 octet-align=1
a=rtpmap:111 AMR/8000/1
a=imageattr:111 octet-align=0
a=fmtp:111 octet-align=0
a=rtpmap:3 GSM/8000/1
a=rtpmap:101 telephone-event/8000/1
a=fmtp:101 0-16
a=pcfg:1 t=1
a=sendrecv
a=rtcp-mux
a=ssrc:4107027510 cname:9f47ab39da7d76d6d132d444e867dc38
a=ssrc:4107027510 mslabel:6994f7d1-6ce9-4fbd-acfd-84e5131ca2e2
a=ssrc:4107027510 label:doubango@audio

version v2.x.,code under branches/2.0
OS:Android

Original issue reported on code.google.com by swarnim...@gmail.com on 12 Aug 2013 at 1:51

Attachments:

incorrect_sdp.pcap

chenguangming / doubango

Incorrect offer-answer model #298