Subject: [MMUSIC] RTSP: Changing of transport parameters using SETUP

From: Magnus Westerlund <[email-masked]>
Date: Thu, 14 Jul 2005 13:46:39 +0200

Hi,

The spec does currently allows the usage of SETUP to change transport 
parameters both in ready and play mode. If a server doesn't support the 
functionality it is supposed to respond using 455 (Method not allowed in 
this state). However this generates an issue. If a client gets back a 
455 when the server is play state, then it can't determine if the server 
supports this operation in ready mode or not.

Possible solutions:

1. Require the support of changing of transport parameters in ready 
state from all servers.

2. Recommend that clients checks also in ready state?

3. If supporting this functionality it shall be supported in both ready 
and play mode.

4. Forbid it in play mode

5. Ignore the issue

Comments

Cheers

Magnus Westerlund

Multimedia Technologies, Ericsson Research EAB/TVA/A
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From: Dave Singer <[email-masked]>
Date: Thu, 14 Jul 2005 15:14:46 -0700

At 13:46  +0200 14/07/05, Magnus Westerlund wrote:
>Hi,
>
>The spec does currently allows the usage of SETUP to change 
>transport parameters both in ready and play mode. If a server 
>doesn't support the functionality it is supposed to respond using 
>455 (Method not allowed in this state). However this generates an 
>issue. If a client gets back a 455 when the server is play state, 
>then it can't determine if the server supports this operation in 
>ready mode or not.
>
>Possible solutions:
>
>3. If supporting this functionality it shall be supported in both 
>ready and play mode.
>

from Apple:  we like (4).  Perhaps not a surprise.
-- 
David Singer
Apple Computer/QuickTime

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From: Sean Sheedy <[email-masked]>
Date: Thu, 14 Jul 2005 15:16:06 -0700

> 1. Require the support of changing of transport parameters in ready 

I don't like this.  In some environments (such as cable TV), changing
transport parameters after the initial SETUP isn't feasible.

> 2. Recommend that clients checks also in ready state?

I think this is the best choice.

> 4. Forbid it in play mode

Is anyone using re-SETUP during play mode for bandwidth throttling?  If
so, we don't want to forbid it.
 
> 5. Ignore the issue

Sean

-- 
Sean Sheedy                                         [email-masked]
(503) 531-6427

---

From: Dave Singer <[email-masked]>
Date: Thu, 14 Jul 2005 15:14:46 -0700