WebApp Sec: Re: How to prevent Internet Explorer from locally caching pages

[Liam Quinn <liam () htmlhelp com>]

On 4 Apr 2003, Adrian Caneva wrote:

> Expiration headers seem to be ignored by Internet Explorer behind a Proxy 
> server when using BACK / FORWARD buttons.
> On Microsoft's Knowledge Base Article  234067 (HOWTO: Prevent Caching in 
> Internet Explorer) I've found that in fact this can happen.
> And I could verify that, behind a Proxy, IE (6.0, 5.5, 5.0) gets the page 
> from local disk cache although Expire = -1 header should force it ask the 
> web server for an updated version.
FWIW, IE's behaviour seems to be in agreement with the HTTP/1.1 
specification:

   By default, an expiration time does not apply to history mechanisms.
   If the entity is still in storage, a history mechanism SHOULD display
   it even if the entity has expired, unless the user has specifically
   configured the agent to refresh expired history documents.

http://www.w3.org/Protocols/rfc2616/rfc2616-sec13.html#sec13.13

-- 
Liam Quinn