Re: Question on EXT_CENC in draft-ietf-rmt-flute-revised

Hello Lakshminath,

> I have a question on EXT_CENC specified in 
> draft-ietf-rmt-flute-revised.  As per the draft, the header extension 
> is "ALC PI Specific."  The question I have is whether the extension 
> can be used for any ALC object.  If not, how is content encoding of an 
> ALC object signaled?

In the FLUTE context, EXT_CENC is only meant to specify
the (optional) encoding of an FDT Instance. If an object (that is not
an FDT Instance) carried in a FLUTE session is to be content
encoded, then it's signaled in the "Content-Encoded" attribute of
the associated file element in the FDT Instance. You'll find an
example in Appendix B.

If ALC is used by an application that is not FLUTE, then it's
unclear to me whether EXT_CENC can be used or not for any
ALC object or not... I don't see any good reason to prevent it, though.
Maybe it would be good to move it's definition to the ALC I-D and
make clear in the FLUTE I-D that in this context it is restricted
to an FDT Instance. Opinion?
Cheers,

    Vincent