[MMUSIC] RTSP 2.0: Inconsistent identifiers between Range and Accept-Ranges

Magnus Westerlund <magnus.westerlund@ericsson.com> Fri, 23 August 2013 08:38 UTC

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Date: Fri, 23 Aug 2013 10:38:59 +0200
From: Magnus Westerlund <magnus.westerlund@ericsson.com>
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Subject: [MMUSIC] RTSP 2.0: Inconsistent identifiers between Range and Accept-Ranges
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WG,

One of Elwyn's comments are in regards to the lack of IANA registry for
new Accept-Ranges formats. My immediate reaction is that should not be
needed as range formats are common between the Range and Accept-Ranges
header. But, then I checked our definitions are realized that we have
made a blunder to not reuse the range identifiers from Range in
Accept-Ranges.

To resolve this issue we either can do two things.

1) Change the Accept-Ranges header to use the Range header identifiers.
This will affect any implementations of Accept-Ranges header and the
values it uses. Because Accept-Ranges has the following identifiers:

Accept-Ranges: NPT SMPTE UTC

While ranges has the following:
Range: npt, smpte, smpte-30-drop, smpte-25, clock

So in addition to being different there are actually more resolution in
formats for Range header than in Accept ranges.

2) Define a registry and clarify the mapping between the accept-ranges
identifiers and the Range ones.

I personally think 1) is long term better. But, the question is how it
affects any existing implementations of 2.0?

Feedback much desired

Cheers

Magnus Westerlund

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