Hello, My PJSIP client is reporting a time out (408) and dropping a call (sending a BYE message) just a few seconds after it has been successfully established. I'm trying to understand why this is happening. The client connects via a proxy server which happens to be front-ending a pool of real servers. Therefore, upon processing an INVITE from my client the proxy sends a REFER message telling my client the real address to be contacted (specified in the Refer-To field). My client sends the new INVITE, still via the original proxy, which is processed fine, gets the 200 OK, and everyone is happy, the connection is established. In parallel to the above, my client sends NOTIFY messages to the proxy telling it about the status of the REFER message it received before. It first sends a NOTIFY Trying message, and upon successful call establishment with the requested server it sends a NOTIFY OK message to the proxy ... and it keeps sending them, one after another. These NOTIFY messages get a "100 Trying" response each from the proxy, which my reading of RFC 3515 tells me is acceptable (as well as any appropriate 4xx-6xx class response). Some times it happens that the original proxy decides to process the original INVITE directly so no REFER message is sent to my client. In these cases, the connection is established properly and the call is never dropped. The session goes just fine. The only thing that puzzles me is why PJSIP keeps repeatedly sending the NOTIFY OK messages after the call has been successfully established. Isn't just one enough? Or is it that the "100 Trying" responses are not expected by PJSIP? So, any ideas where this 408 timeout might be coming from? Thank you, -- Pedro
