[xiph-rtp] Lots of proposals

[David Barrett]

Tor-Einar Jarnbjo wrote:
> David Barrett wrote:
> 
>> You've proposed sending codebooks at the stream rate -- a safe, 
>> reasonable, but very slow solution.  There are other choices that are 
>> still safe but much faster, especially with acknowledgement.  Indeed, 
>> if you choose not to play nicely with other TCP streams, you can even 
>> go *faster* than TCP using UDP (and for realtime data as small as 5KB, 
>> this might be a fine choice).
> 
> Not if you are concerned about implementation effort. Of course you can 
> reimplement parts of the already available TCP stack to achieve reliable 
> stream transfers over UDP, but that would have to include ack or resend 
> messages from the client and some sort of bandwidth usage control. 
> Without a two way communication, the server will never know for sure 
> that the codebook has been completely received by the client, so that it 
> can start streaming the audio content.

Yes, we're not covering any new ground here:

- Yes: Two way communication would require ACKs, and a good way to do 
that would be to model TCP.  And there are other good ways.

- Yes: One way communication doesn't get the benefit of ACKs, clearly. 
And without ACKs, the server is just guessing, clearly.

I think we're in violent agreement.  I'm not asking you to implement 
this.  I'm not asking you to recommend this.  I'm merely asking that you 
don't forbid those who want to do so (ie, me) from doing so.


>> Personally, I think Vorbis and Theora (even Speex -- it doesn't send 
>> codebooks, but it does have stream parameters that must be delivered 
>> reliably) are so similar in this respect that we'd be silly not to use 
>> the same approach for all.  Do you have an opinion on this?
> 
> I do not have any detailed knowledge about Theroa, but I don't see any 
> similarities between Vorbis, Speex and FLAC justifying the effort to try 
> to find a common RTP solution for them.  ...

Ok, so you believe Speex and FLAC needn't be covered by the same RTP 
spec.  What about Theora?

In my case, the Theora codebook is about 2KB.  Thus I have exactly the 
same problem between Vorbis and Theora, and I would like to solve it in 
exactly the same way.  It would seem that the reasoning that goes into 
the Vorbis spec is extremely similar, if not identical to the reasoning 
that will go into the Theora spec.

-david