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Do HTTP/1.0 caches understand max-age?

My question is about: https://www.mnot.net/blog/2007/05/15/expires_max-age

They're saying:

The problem with that line of reasoning is that HTTP versions aren’t black and white like this; just because something advertises itself as HTTP/1.0, doesn’t mean it doesn’t understand HTTP/1.1 (see RFC2145 for more).

But here they are saying:


If a response includes both an Expires header and a max-age directive, the max-age directive overrides the Expires header, even if the Expires header is more restrictive. This rule allows an origin server to provide, for a given response, a longer expiration time to an HTTP/1.1 (or later) cache than to an HTTP/1.0 cache.

So or the article is incorrect, or W3 is incorrect (or I'm wrong :p). With the last sentence, W3 means you can give a different expiration time to a HTTP/1.1 cache (or later), compared with a HTTP/1.0 cache. You can do this by using max-age and the Expires header.
So they can only say something like that, by assuming the HTTP/1.0 cache will ignore the max-age, because otherwise you will just have the same expiration time for all the caches (HTTP/1.0 and HTTP/1.1 et cetera).

So what is true about HTTP/1.0 caches understanding max-age?
Maarten Bruins
Maarten Bruins
David FavorLinux/LXD/WordPress/Hosting SavantCommented:
All mainstream servers support HTTP1.1 or HTTP2 + none I can find (actually running anymore) support HTTP/1.0, so likely you can just stick with HTTP1.1 + HTTP2 conventions.

If you have a real HTTP1.0 server running, then you'd test against it using your target browser to determine how your server works.
Maarten BruinsAuthor Commented:

And if someone knows how it was back in the days, I'm still interested in how it was and if that article or W3 was wrong.

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