[Live-devel] Fwd: Why is RTSP needed apart from SDP?

[Ross Finlayson]

>Why can't one play unicast just from a SDP description? From a 
>previous message:
>
>>  Ross Finlayson finlayson at live555.com
>>  Wed Oct 1 03:04:23 PDT 2008
>>  You can't (in general) play a unicast stream just by reading a
>>  SDP description, because the SDP description does not, by
>>  itself, contain enough information about the stream endpoints.
>
>What's that missing information?

The client's port numbers.

>
>In detail: I want to transmit live captured unicast audio/video, and
>I'm trying using testMP3Streamer and ffmpeg freely running,
>independently (without establishing sessions because I know my clients
>beforehand,) then clients would use VLC with a SDP file.
>
>That's not working. I'm able to play the audio/video independently,
>it's just concurrently that fails. Is an RTSP server necessary?

In general, yes, if you are streaming via unicast.

We implemented our RTSP server for a reason.  If you want to stream 
via unicast without using a RTSP server, then you might (perhaps) be 
able to get this to work, but you will get no support from me.
-- 

Ross Finlayson
Live Networks, Inc.
http://www.live555.com/