Re: Hit-metering: to Proposed Standard?

On Wed, 20 Nov 1996, Roy T. Fielding wrote:
> I still don't believe that such count-forwarding is appropriate for a
> proposed standard (experimental is okay), since I don't think that
> people disable caching just to record hit-counts (which are already
> known not to be an accurate measure of readers).  Most people disable
> caching by accident, and those that do it on purpose are normally
> looking for Referer and IP/hostname (more than just a request count).

I concur. Hit counts are *inherently* unreliable. The 'hit-metering'
proposal will do very little to attack the fundamental causes of that and
does not address the real reasons most deliberately anti-cached sites
defeat caching. In my experience, it is the requirement for highly
volatile sites where *every single request* will return information that
changes in important ways that leads to deliberate cache defeating. We are
talking shopping baskets, web chat systems, reporting systems for highly
volatile information sources, and similar things. 

Attempts to finess the system for the sake of improving hit counting are
doomed from the start by the simple fact that most *browsers* have their
own user selectable options for caching that are completely independant of
the standards: 'Check every time','Check once per session', 'Never check'.
This *alone* is enough to make efforts to make proxies report hits nearly
irrelevant. Are they reporting 20 repeat hits from someone who 'checks
every time' or 1 new hit each from people who 'Never check'? You don't
know. We don't know. NO ONE knows. A server can *guess* based on referrer
and IP address in their logs, or come very close to exact counts by
anti-caching. But the necessary abstraction of data by the proxies on
summary reports for hit-metering will defeat these efforts in log
analysis and passing raw log information would defeat the *purpose* of

This also does not begin to address the questions of privacy and security
and their impact on the usage of hit-metering.. Many corporate proxies
would more than reluctant to be sending out information about their
internal usages to anyone who asked - they would be actively opposed to

In my view, the hit-metering proposal seems to request large amounts of
work for proxies at nearly no benefit - to anyone.

Benjamin Franz

Received on Wednesday, 20 November 1996 05:42:20 UTC