Re: Byte ranges -- formal spec proposal

Rainer Klute (klute@nads.de)
Thu, 18 May 1995 05:54:54 +0500


> BYTE RANGES WITH URLS AND HTTP
>
> May 16, 1995

A very good proposal and it's nice to have it published and
discussed before it is implemented! This is the way Netscape Comm.
should always take.

Some minor points follow:

>Description of the byterange URL Parameter
>
> * The byte range request is attached to the end of the URL,
> separated by a semi-colon.

What is the "end of an URL"? In

<http://foo/bar?blah>

where is the "end"? Is it before the question mark or behind
"blah". Would a byterange URL be

<http://foo/bar;byterange=4-44?blah>

or
<http://foo/bar?blah;byterange=4-44?blah>

I'd prefer the former one because it integrates much more smothly
with existing applications.

> * The first byte in file is byte number 1.

What is a file? There's not necessarily a file behind a URL, and to
the client this should be totally transparent. Let's call it
document or (even more general) entity.

As other responses indicate, it is more or less a matter of
taste whether to start with 0 or 1. Just pick one (not necessarily
1 :-)) and go for it.

> If at some point there will be multiple simultaneous URL parameters,
> they should be separated by the ampersand character (just like
> multiple values are encoded in the FORM request).

Oh no, please don't pick the ampersand because of its SGMLish
implications!

BTW, some food for more thinking: It may be useful to invent some
notation for set operations, like
<http://foo/bar;(chapterrange=5-12)-((chapterrange=8)+byterange=100-1500))>

Best regards
Rainer Klute

Dipl.-Inform. Rainer Klute NADS - Advertising on nets
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