ACTION-163: Send a resolution on handling non-existing or illegal fragments

Dear all,

I took this action last week, in order to notify all some of the changes 
we have discussed regarding the output of test cases dealing with 
non-existing and illegal fragments. Note that these changes have already 
been committed in the Wiki by Silvia at 
http://www.w3.org/2008/WebVideo/Fragments/wiki/TemporalDimension as she 
has announced today.

The resolution is as follow: in case of an empty fragment, e.g. #t=a,a 
where a>=0, or an non-existing fragment, e.g. #t=a,b where a>b, we 
consider that a media fragment aware UA knows beforehand that this will 
be an empty fragment (resp. an non-existing fragment) and SHOULD therefore:
   - a) if the UA does not have the setup data for this media, issue a 
Range request with just "include-setup", and receive the setup data in a 
206 Partial Content response.
   - b) if the UA has already the setup data for this media, do nothing 
(no HTTP request issued).

The situation where no request is issued might be perceived as 
irritative. The rationale is that this is what currently happens when 
one click on a non-existent fragment of an HTML page.

If you disagree with this resolution, then please shout!
Next step will be to modify the WD with this modification. Anyone?
Tracker, this is ACTION-163.

   Raphaël

-- 
Raphaël Troncy
EURECOM, Multimedia Communications Department
2229, route des Crêtes, 06560 Sophia Antipolis, France.
e-mail: raphael.troncy@eurecom.fr & raphael.troncy@gmail.com
Tel: +33 (0)4 - 9300 8242
Fax: +33 (0)4 - 9000 8200
Web: http://www.eurecom.fr/~troncy/

Received on Wednesday, 19 May 2010 08:29:21 UTC