"Christopher A. Martin" <[EMAIL PROTECTED]> writes:
>I should qualify this by saying that if the media is being implemented by
>the specific vendor as symetrical RTP (Sending to the remote host using the
>listening port as the source port), otherwise the source port could be some
>other random port, in the event that the vendor implements asymetrical RTP.
"Symmetric RTP" was used to mean that one party ignores the
destination address/port in SDP, and sends its packets to the
source address:
http://www.ietf.org/proceedings/01aug/slides/avt-6/sld007.htm
(Please use STUN instead of this).
A multicast RTP implementation typically uses two UDP sockets,
the receiving socket is bound(� to destination address and the
sending socket is connected to the destination address. This is
because of limitations of socket interface on many operating
systems.
When such a RTP implementation is used for unicast, it is
convenient to bound the receiving socket to the destination
address the application advertises in its own SDP, and connect
the sending socket(s) to the address(es) got from the remote
SDP. Such an application can close the sending socket and create
a new one each time it receives a new SDP in re-INVITE, so the
source address changes in middle of the session.
BR,
Pekka
�) Actually it is bound to INADDR_ANY and uses IP_ADD_MEMBERSHIP, however.
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