We have a Presence install that is working well over every connection except for Cisco IPSEC VPN over a Verizon Cellular connection. If I disconnect the cellular connection and connect over my hotel wireless, and the same VPN profile, the CUPC works just fine. If we disconnect the wireless and reconnect the cellular and the same VPN profile, we can not connect to presence, or if we do connect to presence, it does not show status or allow use of the softphone.
The presence server is configured to use the TCP default listener, and the VPN headend is a IOS router doing the IPSEC for the clients.
Verizone must be stripping some packets for SIP possibly. Why, Im not sure. You would have to sniff the packets out to see if you are actually sending this.
Im assuming you are connecting to verizon data network correct? Im wondering if Verizon is blocking something on their network for this kind of traffic.
Tried another carrier like sprint? I know on my sprint EVDO connection, I can get online with laptop, start up OCS and make SIP calls. Works pretty good. (and see status, etc) I have not tried with CUPS yet, but assuming it's the same basic premise using SIP, it should be the same results.
I would agree with this other than we are using a VPN connection over the cellular, and they can not strip what is in the VPN tunnel. We have not been able to test on a different network since we only use Verizon. I will see if I can borrow one from someone to test that, but again it is still inside of a VPN client.
You would need to sniff the packets then to see if the SIP 5060 or 5070 is actually making to/from the VPN tunnel. You should be able to enable logging on the CUPC client and also on the Presence Server RTMT to watch the requests coming and going.