[Windows Mobile Software Development] Sleuth255:
The goal of this thread is to get Vonage softphone accounts working with WM6 Internet Calling again. I'm going to use my cosmic moderation powers to delete without notice all posts that don't actually contribute to this effort. I don't want any "how do I set up provisioning..." posts cluttering up this thread. If you are having this issue, please respond to the poll so Vonage can get an idea of the affected XDA posters. If you answer no, then please post here! TMK all Vonage softphone users are affected, so you would be one of a kind.

To aid with troubleshooting, I'm also willing to (temporarily) share my Vonage softphone provisioning information with trusted SIP gurus who wish to participate. Post here if you're interested.

Ok, Here's what we know:

Sometime during the week of June 18th, Vonage softphone accounts stopped working on all WM6 builds that had Internet calling activated

SJPhone however, continues to function normally.

WM6 Internet calling still functions normally with other SIP service providers.

Given this information, I installed the Airscanner packet sniffer on my Tytn. The 30 day free trial for this sniffer can be found here. This nifty little utility creates packet captures that can be read by Ethereal. The current version of Ethereal is located here.

I next attached Airscanner to the IEEE 802.11b/g Compatible WiFi adaptor on my TyTN, connected to my home AP and turned my TyTN's phone radio off. Then I proceeded to capture the sip initiation sessions with SJPhone (worked fine) and WM6 Internet Calling (showed "No Service" after long "Searching" delay). Everybody who wants to participate in this exercise should connect this way btw. Let's not cloud the troubleshooting effort with the ideosyncracies of 3G connectivity.

Here are the relevant packet captures (click images for full size versions in new browser windows)

Internet Calling Registration Packet

SJPhone Registration Packet

Initial Analysis

As it turns out, the SIP register packet sent by Internet calling is being ignored by Vonage's SIP servers at sphone.vopr.vonage.net:5061. WM6 Internet Calling retrys the original Registration request 11 times then gives up. However, the registration packet is immediately accepted when sent by SJPhone. This points to a formatting issue with Internet calling's SIP Registration packet.

SJPhone is also sending a binding request to the SoftJoys STUN server but you can clearly see that the response from Vonage is occuring directly directly after the STUN bind request and is in response to the original UDP packet and not the STUN bind packet (response from softjoys is not shown but is further down in the conversation). Conclusion: STUN isn't the reason why SJPhone is succeeding here.

So it would appear to be something in the REGISTER request itself. Here are the differences I've noticed:

the REGISTER sip URI contains the :5061 port suffix in SJPhone and not in WM6. However, both programs are sending the request to port 5061 at sphone.vopr.vonage.net. This probably isn't the issue

the source port for SJPhone is 5060 and for WM6 its 1153. This may be the issue IMO. Perhaps Vonage added firewall rules that restrict outbound connections to known SIP ports. I'm working on coming up with a way to test this currently.

the contact binding information is completely different between WM6 and SJPhone. Could this be an issue? Any SIP gurus out there, feel free to comment!

Is anybody seeing anything else here?

Next steps:

Once we've identified the likely causes for the failure, I will get on the phone with Vonage technical and go over our findings. I may even link them to this thread. Hopefully the outcome will be a quick change to Vonage's firewalls or SIP servers. Also, it would be nice to find out more about WM provisioning/registry settings to handle these:

How to provision STUN servers

How to force the source port from a random 1000-2000 to 5060. BTW: setting the enableport5060 value to a 1 doesn't change this. It merely causes Internet Calling to start listening on port 5060.

Let's get this issue solved so Vonage Softphone accounts can once again work with Windows Mobile!

... or we Vonage users could just close our accounts and just install asterisk or use a different service that works I guess... ;)