Re: Must-revalidate [was Re: Warning: header, need origin]

Larry Masinter:
>
>Is there no useful meaning to max-age=0 other than "must-validate"?

The difference between "max-age=0" and "must-revalidate" for caches
that play by the transparency rules is that, if revalidation fails
because of network failure:

- with "max-age=0", you return a stale 200 (OK) response with a
  warning header attached

- with "must-revalidate", you return a 5xx error response

So must-revalidate is more than just "really really max-age=0".

Speaking in road-sign metaphors, "max-age=0" means "speed limit 50
Km/h", while "must-revalidate" means "WARNING: sharp turn: safe
maximal speed 50 Km/h".  If you ignore the first, you only sin against
community standards.  If you ignore the second, you end up upside down
besides the road.

Koen.

Received on Thursday, 11 April 1996 12:05:32 UTC