Re: WGLC p6 4.2.1

On 20/03/2013, at 5:00 AM, Roy T. Fielding <fielding@gbiv.com> wrote:

> On Mar 17, 2013, at 3:39 PM, Adrien W. de Croy wrote:
> 
>> Hi all
>>  
>> I see there were some changes made to the 3rd bullet point in 4.2.1 about selection of representations to update with a 304.
>>  
>> The new text hints that dates other than those received in a previous Last-Modified can be used to generate a conditional request with If-Modified-Since. 
> 
> Yes, because that has always been allowed, including within my
> original definition when I invented it in 1993.  IMS is used for
> both cache updates and restricted-window traversals (e.g., MOMspider).

Indeed; I've seen a widely-used browser doing it.

Cheers,


> 
>> However, there are a number of side-effects with introducing this concept.
> 
> It is not being introduced.  p6 was originally extracted to only talk
> about the use of IMS in caching, but it still needs to deal with all
> valid uses of IMS that were defined in RFC2616, RFC2068, and RFC1945.
> The recent changes in p6 just restores the prior definitions.
> 
> This dual use of IMS has never been a problem in the past, though
> concerns about it was one of the main reasons for introducing etags
> as a replacement for validation.
> 
> ....Roy

--
Mark Nottingham   http://www.mnot.net/

Received on Wednesday, 20 March 2013 01:08:22 UTC