On Tue, 9 Apr 2002, Sagi Bashari wrote: > From: "Nadav Har'El" <[EMAIL PROTECTED]> > > On Tue, Apr 09, 2002, Eli Marmor wrote about "Re: OT: Transparent Proxies > in Israel": > > > But back to the original question: Can anybody list the ISP's that > > > don't use transparent proxies, even not for ADSL users who access > > > foreign (long distance) sites? > > > > No, I never did such research. When I was connected to Netvision's ADSL > > it looked like we did not have a transparent proxy, but I'm not sure. > > In Barak's connection, I did notice a transparent proxy in place. > > > > I think that even if the ISP run transparent proxy, or actually any kind of > HTTP proxy, they should query the server in any case - to see if the content > is modified. If it does, it redownloads the content, and if not, it serves > from cache. In any case, it shouldn't serve old data without checking first.
This is true when no-cache is included in the request headers. A couple of years ago I followed such transactions on both ends, out of curiosity. Inclusion of a no-cache header invariably caused the proxy to forward the browser query verbatim to the site. This conforms to the RFC. On the browser side, Netscape generated the header when ctrl-refresh was pressed. MSIE generated a no-cache header with different capitalization which was ignored by that particular versio of that particualar proxy. The web server sometimes responded to these requests by serving the file, sometimes with a 304 response. -- Thanks, Uri http://translation.israel.net ================================================================= To unsubscribe, send mail to [EMAIL PROTECTED] with the word "unsubscribe" in the message body, e.g., run the command echo unsubscribe | mail [EMAIL PROTECTED]
