ISPs Caching Web Pages

Do you have a question? Post it now! No Registration Necessary.  Now with pictures!

This is a "heads up!"

When a Web page is frequently or even constantly updated, it is
appropriate the server to send the Cache-Control header field (described
in RFC 2616 Section 14) to prevent caching, at least in a shared cache
(e.g., by an ISP).  However, it appears that some ISPs ignore the
Cache-Control header field.

Among those ISPs is RoadRunner.  When I view certain Web pages that have
the header field
    Cache-Control: max-age=15, private
(meaning (1) expire any cached version after 15 seconds and (2) do not
cache in a shared environment), the IP address associated with the pages
is owned by RoadRunner and does not trace back to the pages' Web servers.

If you see a similar situation affecting either your own Web sites or
your Web browsing, you should immediately contact the ISP to which the
IP address traces and insist they fully honor Cache-Control header fields.


David E. Ross
< .

Anyone who thinks government owns a monopoly on inefficient, obstructive
bureaucracy has obviously never worked for a large corporation.
1997 by David E. Ross

Site Timeline