Changes between Version 2 and Version 3 of PotentialWork


Ignore:
Timestamp:
Jan 31, 2012, 2:16:20 PM (8 years ago)
Author:
david@…
Comment:

Added section on Increasing precision of Last-Modified header

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  • PotentialWork

    v2 v3  
    1010 * [http://en.wikipedia.org/wiki/Meta_refresh wikipedia]
    1111 * [http://www.w3.org/mid/4CA6E042.1040406@gmx.de list discussion]
     12
     13== Increasing precision of Last-Modified header to allow sub-second granularity ==
     14It would be nice if the Last-Modified
     15header could (optionally) carry more precision that one second, for the
     16benefit of clients that wish to reliably detect when a server has
     17changed its output faster than once per second.  For example:
     18
     19  Last-Modified: Fri, 27 Jan 2012 20:21:10.011483 GMT
     20
     21Note that it is possible to get around the current one-second limitation
     22using ETags, but it would be more convenient if this could be done directly in the Last-Modified header, because: (a) clients would know that it is a (high-resolution) last modified time as opposed to an opaque string in an ETag; and (b) servers would not have to set both the Last-Modified header and the ETag header when simply trying to indicate a high-resolution last modified time.
     23
     24This is relevant to high-speed distributed systems that are based on HTTP.
     25
     26See also:
     27 * [http://lists.w3.org/Archives/Public/ietf-http-wg/2012JanMar/0316.html Email thread]