You are here: CSP Developer’s Guide: Internet Protocol > 7 Interworking > SIP-UPDF Tunneling
Overview
SIP-UPDF tunneling carries PSTN signaling across two CSPs with SIP. The Request for Service message presented to the host contains TLVs in UPDF format. SIP UPDF is proprietary to Dialogic as it uses proprietary Multipurpose Internet Mail Extensions (MIME) multipart.
SS7 ISUP information is encapsulated within the SIP messages that flow across each CSP. The following is a sample of the message encapsulation:
Content-Type: Application/Multipart
Content-Length: 482
Content-Type: multipart/mixed; boundary="de5=_78=_e5d"
--"de5=_78=_e5d"
Content-Type: application/sdp
v=0
o=sip 14999 14999 IN IP4 135.119.55.42
s=SIP_Call
c=IN IP4 135.119.55.48
t=0 0
m=audio 14980 RTP/AVP 18
a=rtpmap:18 G729/8000
--"de5=_78=_e5d"
Content-Type: application/SS7 ISUP; version:EXCEL-UPDF
Content-Transfer-Encoding: binary
03 00 33 00 67 00 0c 27 4e 00 02 00 05 27 25 00 02 21 00 27
46 00 01 02 27 17 00 08 01 01 0a 86 25 00 00 12 27 18 00 0a
01 10 81 0a 0a 31 35 55 12 12 27 7d 00 07 00 01 00 06 00 01
00 27 61 00 08 00 00 00 04 01 00 00 00 27 92 00 04 87 77 37
30 27 93 00 04 00 00 3a 84 27 b0 00 02 01 12 27 b1 00 02 01
02 27 7e 00 03 08 00 00
--"de5=_78=_e5d"--