[Linphone-users] Andoird Nat problem

[>> jlnovo]

Hi to All

 

A newbie question: I have two android linphone clients in two separated private lans behind Nats. The configuration is something like this:

 

Android1 --- Time Capsule (bridge) --- Router --- >    INTERNET    < -- Router --- Time Capsule (Bridge) --- Android2

 

The time capsules are bridges, so they are not suppose to do any NAT. When android1 calls android2, android2 receives the call notification but when it answers, no response is received on android1 (so it continues to ring). If android2 tries to call android1, the call doesn't even reach. (linphone closes)

 

If the caller client cancels the call, the cancel is detected on the receiving device.  In the receiving  android log the “Via” header has the correct public IP of the caller. It seems the problem is the NAT/firewall transverse of the caller's lan.

 

So if the receiver android "rings" when called, but its “answer” is not detected by the caller; does this means that the blocking occurs when the UDP of the audio/video RTP is trying to being established?  Or it's blocked at the SIP UPD session establishment?  

I'm using the sip.linphone.org service, and the version of the android linphone is 1.1.4

Thanks very much in advance

Kind Regards