From: Bill Stewart <stewarts@ix.netcom.com>
Date: Wed, 26 Nov 1997 17:36:21 +0800
To: cypherpunks@toad.com
Subject: Re: Security Risks in HTTP Proxy Agents (Re: Anonymizer rocks! (Re: Anonymity at any cost, from The Netly News))
In-Reply-To: <199711251009.KAA01273@server.test.net>
Message-ID: <3.0.3.32.19971126012116.00725920@popd.ix.netcom.com>
MIME-Version: 1.0
Content-Type: text/plain



Besides the risks of using proxy.evil.nsa.mil or proxy.blacknet.net,
there are other subtle things that a proxy server could do.
For instance, replacing banner ads is easy - you can't recognize them all,
but ad.doubleclick.net and linkexchange.com are easy targets;
an anonymizing proxy might replace those ads with its own,
or at least with static images that load faster.
This has a lot of implications when using the proxy to access
advertising-supported web sites, and there have been lawsuits over
web services that provided access to other web-based news services
while adding their own advertising banners in another frame
(one such target was totalnews.com.)

Of course, if you want to make advertising banners go away,
you can start by aliasing ad.doubleclick.net to 127.0.0.2 or whatever;
I've found it loads much faster this way :-)
				Thanks! 
					Bill
Bill Stewart, stewarts@ix.netcom.com
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