Re: AOL aid in an open source IM project

From: Stephen D. Williams (
Date: Thu Mar 29 2001 - 21:38:08 PST

Steve Bush wrote:
> For several months, IM clients like Yahoo and MSN Messenger were able to
> interoperate with AOL using the AIM protocols. Interoperability had a
> great benefit for users but raised a ton of legal and business issues.
> It also started a compatibility war between AOL and other IM clients.
> AOL would detect other IM clients calling their servers and proactively
> shut down thsee connections. The IM client community would hack around
> the AOL change and interoperability would be restored until AOL figured
> out how to detect the offenders. This continued for several months and
> was quite intense for the developers involved.
> AOL finally got smart and combined coding and copyright practices
> together. IMHO, their solution though pisses me off is quite ingenious.
> They built into the AOL protocol the requirement that a consistent array
> of bytes must be on the users machine. To continue using the AOL
> connection, an IM client needs to respond to a request for these bytes,
> apply an MD5 hash, and return the result. In essence, they turned
> aim.exe into an encryption key. The entire aim.exe needs to be
> available. Developers cannot reproduce the array of bytes because this
> violates copyright law.

This has been worked around before in ROM's and client ID's. I've seen
both IBM and Netscape/Mozilla spoofed. The trick there is to simply
make the overall message indiate a different owner while still
mentioning the appropriate strings.

Of course in the case of a whole client, this is tougher. I could
imagine that instead of distributing their client, a violation of their
copyright, you could have a single copy in one or more servers and have
each non-AOL client ask these servers for the 'key' computation...

> Thx
> Steve

Stephen D. Williams
43392 Wayside Cir,Ashburn,VA 20147-4622 703-724-0118W 703-995-0407Fax 

This archive was generated by hypermail 2b29 : Fri Apr 27 2001 - 23:15:13 PDT