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04:07:38.417615 IP (tos 0x0, ttl  64, id 53747, offset 0, flags [none], proto 17, length: 900) 72.36.152.66.5080 > 75.155.167.90.2363: UDP, length 872
INVITE sip:faxmodem@172.16.40.251:5091 SIP/2.0
Via: SIP/2.0/UDP 72.36.152.66:5080;branch=z9hG4bK599ae28e;rport
From: "callweaver" <sip:callweaver@72.36.152.66:5080>;tag=as21488973
To: <sip:faxmodem@172.16.40.251:5091>;tag=e2da74601fa66a99i0
Contact: <sip:callweaver@72.36.152.66:5080>
Call-ID: 56fbdd27507b4e143b5b8cd029953915@72.36.152.66
CSeq: 103 INVITE
User-Agent: CallWeaver
Max-Forwards: 70
Allow: INVITE, ACK, CANCEL, OPTIONS, BYE, REFER, SUBSCRIBE, NOTIFY
Content-Type: application/sdp
Content-Length: 344

v=0
o=root 10790 10791 IN IP4 72.36.152.66
s=session
c=IN IP4 72.36.152.66
t=0 0
m=image 14756 udptl t38
a=T38FaxVersion:0
a=T38MaxBitRate:14400
a=T38FaxFillBitRemoval:0
a=T38FaxTranscodingMMR:0
a=T38FaxTranscodingJBIG:0
a=T38FaxRateManagement:transferredTCF
a=T38FaxMaxBuffer:300
a=T38FaxMaxDatagram:300
a=T38FaxUdpEC:t38UDPFEC

04:07:38.525503 IP (tos 0x68, ttl 237, id 1549, offset 0, flags [none], proto 17, length: 728) 75.155.167.90.2363 > 72.36.152.66.5080: UDP, length 700
SIP/2.0 200 OK
To: <sip:faxmodem@172.16.40.251:5091>;tag=e2da74601fa66a99i0
From: "callweaver" <sip:callweaver@72.36.152.66:5080>;tag=as21488973
Call-ID: 56fbdd27507b4e143b5b8cd029953915@72.36.152.66
CSeq: 103 INVITE
Via: SIP/2.0/UDP 72.36.152.66:5080;branch=z9hG4bK599ae28e;rport=5080
Contact: 3Com Fax Modem <sip:faxmodem@172.16.40.251:5091>
Server: Linksys/SPA2102-5.1.12
Content-Length: 263
Content-Type: application/sdp

v=0
o=- 8669 8669 IN IP4 172.16.40.251
s=-
c=IN IP4 172.16.40.251
t=0 0
m=image 16406 udptl t38
a=T38FaxVersion:0
a=T38MaxBitRate:14400
a=T38FaxRateManagement:transferredTCF
a=T38FaxMaxBuffer:200
a=T38FaxMaxDatagram:200
a=T38FaxUdpEC:t38UDPRedundancy