Re: TRACE as traceroute

> One of the reputed purposes of the TRACE method is (I believe) a
> traceroute-like mechanism through Web proxies.  To that end, I think it
> would be useful if proxies added a timestamp to the Via: header that
> they add to a TRACE response.  Because comments are allowed in the Via:
> syntax, this could actually be done without changing the protocol. (But
> it would be nice to permit more than one comment by changing the syntax
> from "comment" to "*comment".)

The goal was to minimize the Via syntax overhead, since it will be required
for all HTTP/1.1 intermediaries (proxies and gateways).  There is
only one comment *per-entry*, and even that is discouraged.  We don't
need a timestamp in general, but I suppose adding one within the
comment ONLY during TRACE requests would be good implementation advice.

 ...Roy T. Fielding
    Department of Information & Computer Science    (
    University of California, Irvine, CA 92717-3425    fax:+1(714)824-4056

Received on Friday, 28 June 1996 05:45:33 UTC