On Sat, Sep 6, 2008 at 6:04 AM, Elison Niven <[EMAIL PROTECTED]> wrote: > > Hi, > > I am facing a problem that when I send a 200 OK, a remote UA immediately > starts sending RTP after sending the ACK before my device has yet managed to > opened that port. > > The result is that my device sends an ICMP for the first two received RTP > packets. > > Is this behavior normal or should I not wait for the ACK but open the RTP > listen port as soon as I send the 200 OK?
You should not wait for ACK. You should assume that RTP can arrive immediately after sending the answer in 200 OK. One way to solve this would be to open your RTP port first then send the 200 OK. Here is a quote from section 6.1 of RFC 3264 that addresses this: Once the answerer has sent the answer, it MUST be prepared to receive media for any recvonly streams described by that answer. It MUST be prepared to send and receive media for any sendrecv streams in the answer, and it MAY send media immediately. The answerer MUST be prepared to receive media for recvonly or sendrecv streams using any media formats listed for those streams in the answer, and it MAY send media immediately. -- Raj Jain _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
