SIP Register Request: UE to ATCF
The following is an example of the SIP REGISTER request the UE sends to the ATCF/ P-CSCF.
REGISTER sip:home1.net SIP/2.0 Via: SIP/2.0/UDP [5555::aaa:131313:ccc:eee];comp.sigcomp;branch=z9hG4bRnasiuen8 Max-Forwards: 70 P-Access-Network-Info: 3GPP-UTRAN-TDD; utran-cell-id-3gpp=234151DOFCE11 From: <sip:user1_public1@home1.net>;tag=2hiue To: <sip:user1_public1@home1.net> Contact: <sip:[5555::aaa:bbb:ccc:eee];comp=sigcomp>;+sip.instance="<urn:gsma:imei:90420156- 025763-0>;+g.3gpp.icsi-ref="urn%3Aurn-7%3gpp-service.ims.icsi.mmtel" Call-ID: E05133BD26DD Authorization: Digest username="user1_private@home1.net", realm="registrar.home1.net", nonce="", uri="sip:home1.net", response="" Security-Client: ipsec-3gpp; alg=hmac-sha-1-96; spi-c=23456789; spi-s=12845678; port-c=1234; port-s=5678 Require: sec-agree Proxy-Require: sec-agree CSeq: 1 REGISTER Supported: path, gruu Content-Length: 0