today we discoverd some weird behavior of our WLAN-VoIP problem.
The mobile device does a registration request. After some time with no answer it does the registration request again. Shortly after this there are two registration confirm messages to the device. But the device answers with a deregistration request and then is deregistrated.
I think the problem is that the device gets this two registration confirms and then says: Hey I don't want to be registered to two of you. So it sends a deregistration request.
I hope you understand what I mean
Do you have any clou why this happens? Is it a WLAN problem or is the problem within the communication with the gatekeeper?
Another behavior we have seen is that the mobile device often sends disengage requests and gets disengage confirm messages. Every two minutes. I thought disengage requests are send if a telephone wants to end a call?
Let's now have a look at what happens when the call is over:
1. The two endpoints stop sending the RTP streams. They announce the closing of logical channels (H.245 Request CloseLogicalChannel).
2. The H.245 signalling channel is closed (H.245 command message EndSessionCommand followed by closing of the TCP connection).
3. The main signalling connection is also closed — the endpoints exchange Q.931/H.225.0 messages ReleaseComplete and the TCP connection is closed.
4. Each of the two endpoints informs the gatekeeper about the completed call with the H.225.0-RAS message Disengage Request (DRQ) and the gatekeeper confirms with Disengage Confirm (DCF).
5. And now the call is really over!