Comments on: Two Simple Rules for HTTP Caching http://blog.httpwatch.com/2007/12/10/two-simple-rules-for-http-caching/#utm_source=rss&utm_medium=rss&utm_campaign=two-simple-rules-for-http-caching News, articles and all things HttpWatch Fri, 03 Feb 2012 21:31:46 +0000 hourly 1 http://wordpress.org/?v=3.3.1 By: Ultimate Guide To Web Optimization (Tips & Best Practices) : facedesign.us http://blog.httpwatch.com/2007/12/10/two-simple-rules-for-http-caching/comment-page-1/#comment-41813 Ultimate Guide To Web Optimization (Tips & Best Practices) : facedesign.us Sat, 09 Jul 2011 14:00:04 +0000 http://blog.httpwatch.com/2007/12/10/two-simple-rules-for-http-caching/#comment-41813 [...] Credit: httpwatch [...] [...] Credit: httpwatch [...]

]]> By: Httpwatch Blog http://blog.httpwatch.com/2007/12/10/two-simple-rules-for-http-caching/comment-page-1/#comment-39699 Httpwatch Blog Tue, 14 Jun 2011 15:47:51 +0000 http://blog.httpwatch.com/2007/12/10/two-simple-rules-for-http-caching/#comment-39699 Tom, According the language definition in the spec 'SHOULD NOT' means not recommended: "4. SHOULD NOT This phrase, or the phrase "NOT RECOMMENDED" mean that there may exist valid reasons in particular circumstances when the particular behavior is acceptable or even useful, but the full implications should be understood and the case carefully weighed before implementing any behavior described with this label." If it was disallowed the spec would have used 'MUST NOT'. Far futures expires of more than one year are fairly widely used and we're not aware of any problems triggered by a value more than one year into the future. Tom,

According the language definition in the spec ‘SHOULD NOT’ means not recommended:

“4. SHOULD NOT This phrase, or the phrase “NOT RECOMMENDED” mean that
there may exist valid reasons in particular circumstances when the
particular behavior is acceptable or even useful, but the full
implications should be understood and the case carefully weighed
before implementing any behavior described with this label.”

If it was disallowed the spec would have used ‘MUST NOT’. Far futures expires of more than one year are fairly widely used and we’re not aware of any problems triggered by a value more than one year into the future.

]]> By: Tom Singer http://blog.httpwatch.com/2007/12/10/two-simple-rules-for-http-caching/comment-page-1/#comment-39697 Tom Singer Tue, 14 Jun 2011 15:35:18 +0000 http://blog.httpwatch.com/2007/12/10/two-simple-rules-for-http-caching/#comment-39697 I know this is an old article but you say to set an Expires header to "Sun, 17-Jan-2038 19:14:07 GMT". Going by the HTTP/1.1 spec this is not valid* as "HTTP/1.1 servers SHOULD NOT send Expires dates more than one year in the future" so this should be set to aprox. 1 year in the future. Setting this so far in advance may have adverse effects for browsers and caches who strictly implement the spec as they may reject this request as invalid and not cache the resource. Tom * http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.21 I know this is an old article but you say to set an Expires header to “Sun, 17-Jan-2038 19:14:07 GMT”. Going by the HTTP/1.1 spec this is not valid* as “HTTP/1.1 servers SHOULD NOT send Expires dates more than one year in the future” so this should be set to aprox. 1 year in the future.

Setting this so far in advance may have adverse effects for browsers and caches who strictly implement the spec as they may reject this request as invalid and not cache the resource.

Tom

* http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.21

]]> By: Weekly Links– 2010_10 :MS-Joe (Joe Stagner) http://blog.httpwatch.com/2007/12/10/two-simple-rules-for-http-caching/comment-page-1/#comment-32812 Weekly Links– 2010_10 :MS-Joe (Joe Stagner) Fri, 11 Mar 2011 18:07:15 +0000 http://blog.httpwatch.com/2007/12/10/two-simple-rules-for-http-caching/#comment-32812 [...] Two simple rules for HTTP caching [...] [...] Two simple rules for HTTP caching [...]

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