[xiph-rtp] Difficulties with several RTP streams for a Vorbis stream.

[Ramón García]

> Is it less "surprising" for the media framework to read the setup header
> from an http url?"
That is always posible. The depacketizer can create a socket and open
a connection to a server on its own.

>  I checked the Java Media Framework and it seems as if
> the depacketizer has no access at all to the session descriptor, so it
> wouldn't be able to decode the stream at all if not all necessary info
>  is sent in-band.

That would make it imposible to have any format specific  data in the 
session descriptor. I will check.
 
Sending the codebook data in the RTP data stream is scalable. As it is
sent once to all clients, thus it is not degraded with the number of
clients. It is correct that it is sent to more clients than necessary,
but they way multicasting works that does not degrade server
performance, it is the job of routers to replicate packets until they
reach clients. The issue of redundant sending to all clients also
happens with your method, unless a different IP multicast address is
used for the RTP session that sends codebooks, which would be too much
administrative burden (just acquire a new multicast IP address to
support Vorbis). If the same IP address is used for both sessions, the
packets with the codebooks would be send to all clients, as all of
them are suscribed to the IP multicast address (although the packets
would be thrown away by the operating system of the clients as no
process is listening that port).

Ramon