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   INVITE sip:3000@pbx.rcsnet.ru:5060 SIP/2.0
   Via: SIP/2.0/UDP 91.103.196.12;rport;branch=z9hG4bK32SrX56KHZgya
   Max-Forwards: 70
   From: "" <sip:0000000000@91.103.196.12>;tag=3Z0mjUyp1matN
   To: <sip:3000@pbx.rcsnet.ru:5060>
   Call-ID: e3be7793-cd5a-1235-d195-005056be15c6
   CSeq: 108480740 INVITE
   Contact: <sip:mod_sofia@91.103.196.12:5060>
   User-Agent: FreeSWITCH-mod_sofia/1.9.0+git~20170615T144716Z~5f5fb33ea9~64bit
   Allow: INVITE, ACK, BYE, CANCEL, OPTIONS, MESSAGE, INFO, UPDATE, REGISTER, REFER, NOTIFY, PUBLISH, SUBSCRIBE
   Supported: timer, path, replaces
   Allow-Events: talk, hold, conference, presence, as-feature-event, dialog, line-seize, call-info, sla, include-session-description, presence.winfo, message-summary, refer
   Content-Type: application/sdp
   Content-Disposition: session
   Content-Length: 670
   X-FS-Support: update_display,send_info
   Remote-Party-ID: <sip:0000000000@91.103.196.12>;party=calling;screen=yes;privacy=off
   
   v=0
   o=FreeSWITCH 1497607971 1497607972 IN IP4 91.103.196.12
   s=FreeSWITCH
   c=IN IP4 91.103.196.12
   t=0 0
   m=audio 25638 RTP/AVP 102 9 0 8 104 101
   a=rtpmap:102 opus/48000/2
   a=fmtp:102 useinbandfec=1; maxaveragebitrate=30000; maxplaybackrate=48000; ptime=20; minptime=10; maxptime=40
   a=rtpmap:9 G722/8000
   a=rtpmap:0 PCMU/8000
   a=rtpmap:8 PCMA/8000
   a=rtpmap:104 telephone-event/48000
   a=fmtp:104 0-16
   a=rtpmap:101 telephone-event/8000
   a=fmtp:101 0-16
   a=rtcp-mux
   a=rtcp:25638 IN IP4 91.103.196.12
   a=ptime:20
   m=video 23108 RTP/AVP 103
   b=AS:1024
   a=rtpmap:103 VP8/90000
   a=rtcp-fb:103 ccm fir
   a=rtcp-fb:103 ccm tmmbr
   a=rtcp-fb:103 nack
   a=rtcp-fb:103 nack pli
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