Re: A question about RFC7232#2.2.2

Benedikt Christoph Wolters <benedikt.wolters@rwth-aachen.de> Sun, 04 December 2016 01:00 UTC

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From: Benedikt Christoph Wolters <benedikt.wolters@rwth-aachen.de>
Date: Sun, 04 Dec 2016 01:56:05 +0100
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Subject: Re: A question about RFC7232#2.2.2
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2016-12-04 0:42 GMT+01:00 Michael Lee <michael.lee@zerustech.com>:
> I don't understand why under the circumstance above, at least one of those responses would have a Date value equal to its Last-Modified time.
Strictly speaking I assume the sentence might be slightly wrong.
What might have been meant here is a scenario where two responses were
send in the same second with identical Last-Modified values and at at
least one Date value that is identical to the Last-Modified values.

> And what's the point of ensuring a 60 seconds gap between the Last-Modified
> time and Date?

If the Date and Last-Modified headers are within 60 seconds, it is
considered a weak validator, due to potential timing inconsistencies
between the Last-Modified clock and Date clock.