I am attempting to SUBSCRIBE to notifications from an Alcatel-Lucent-HPSS/3.0.3 server, which provides the VoWifi service for AT&T Wireless.
I'm able to send the SUBSCRIBE and get a 200 OK back, but no NOTIFY ever appears. I've traced an iPhone VoWifi client, which does get a NOTIFY back. The iPhone sends its SUBSCRIBE using UDP instead of TCP and the NOTIFY is delivered via UDP, but me attempting to also use UDP makes no difference. I'd prefer to stick to TCP for everything, so I'm focussing on that. I've tried a number of variations to make my SUBSCRIBE look as much like the iPhone as possible, without success. I've also run tcpdump on the IPsec tunnel to the ALU server, which VoWifi uses, to check whether I'm just somehow missing deserializing an incoming encrypted frame but there is nothing coming from the IPsec tunnel after the 200 OK. I'm hoping someone will recognize an Alcatel-Lucent quirk, "oh you have to include a frobnobulate header in the REGISTER or it will never notify you of anything" or something like that. *SUBSCRIBE tel:+1234567890 SIP/2.0Via: SIP/2.0/TCP [2600:999:1234:5678:0:5c:1234:5678]:6000;branch=z9hG4bK.6PazJ19zhQO4ZBTS;rportCSeq: 1 SUBSCRIBEMax-Forwards: 70Contact: <sip:[2600:999:1234:5678:0:5c:1234:5678]:37363>From: <tel:+1234567890>;tag=uVquAVnWSY5YTo: <tel:+1234567890>P-Preferred-Identity: tel:+1234567890Accept: application/reginfo+xmlSecurity-Verify: ipsec-3gpp; q=0.1; alg=hmac-sha-1-96; ealg=aes-cbc; spi-c=43076203; spi-s=43076202; port-c=33093; port-s=6000Require: sec-agreeProxy-Require: sec-agreeSession-ID: e09f214a7b5241f1Call-ID: speSKrt0MfMajj33hsJy79dCyDSBGKLC61kjDKQw0rVlQBs4Event: regExpires: 600000Content-Length: 0Received:SIP/2.0 200 OKCall-ID: speSKrt0MfMajj33hsJy79dCyDSBGKLC61kjDKQw0rVlQBs4Via: SIP/2.0/TCP [2600:999:1234:5678:0:5c:1234:5678]:6000;received=2600:999:1234:5678:0:5c:1234:5678;branch=z9hG4bK.6PazJ19zhQO4ZBTS;rport=37363To: <tel:+1234567890>;tag=67b4f3d4-692c82b73b587241-1401527-10565-SFrom: <tel:+1234567890>;tag=uVquAVnWSY5YCSeq: 1 SUBSCRIBEContact: <sip:pcgw-prim.imsgroup0-008.oa0ca15pcf.oa1ca.uvp.els-an.att.net:5060;encoded-parm=QbkRBth___MWV1VaFFRSVFE_>Date: Sun, 30 Nov 2025 17:45:27 GMTExpires: 600000Record-Route: <sip:[2001:1890:1f8:220e::1:2]:6000;lr;lsstag=pps-8835-1148.9345>Server: Alcatel-Lucent-HPSS/3.0.3Content-Length: 0* _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
