PJSIP. Outgoing call cut off at 20 sec at certain Wi-Fi networks

Question

What steps will reproduce the problem?

1. Startup application with PJSIP at iPhone 3G with iOS 4.
2. Make outgoing call. Start conversation.
3. Wait 20 seconds.

What is the expected output? What do you see instead?

Actual result: Outgoing call cut off at 20 sec. The call breaks on the phone on which I have called. And the call ends normally according to the log-file.

What version of the product are you using? On what operating system?

• I use iPhone 3g with iOS 4, iPhone 2g with iOS 3, iPhone 3gs with iOS 4, iPhone 4 with iOS 4
• I tried to use PJSIP 1.0.3, PJSIP 1.6, PJSIP 1.7

I have tried another sip clients at this Wi-Fi network:

• Fring - the problem reproduce
• Nimbuzz - the problem NOT reproduce

Please help me to solve this problem.

Answer 1

You'll probably have more luck at SuperUser. Having said that, if one SIP client doesn't have this problem, while the other does, your first step should be to look at what's different between working and non-working clients.

When you say the call cuts off do you mean that media just stops flowing? Does something send you a BYE? (If the media stops flowing, and you terminate your end of the call, does the BYE go out and do you get a 200 OK back?)

Is it possible to use something like Wireshark on the far side of your wireless access point? In other words, can you see media traffic on the first hop past the Wifi network? When the call's cut off, what do you see?

Answer 2

Sounds like you need a keepalive mechanism on the SIP connection. PJSIP supports this. Maybe you will have to enable it.

Use a packet sniffer to see what is actually going on.