I would have thought it better to encode your username and password inside the SOAP body and encrypt them using some form of key known to client and server.

At first, I tried a similar scheme on my own version of the My::SOAP module above. Then I realized that its really a duplication of effort. You end up writing your own credintial validator (eek!) and your own crypto system (double-eek!). I don't see any benifit to this over just using SSL and sending the bare username/password.

HTTP is a protocol not a port. SOAP uses HTTP but can be transmitted over any port . . .

No, I meant HTTP. The problem Schneier and others have with SOAP is that it can be tunnled through HTTP and thus negate the benfits of a firewall. This is because an application-layer firewall not only has to analyze the HTTP headers, but it would also have to take apart the SOAP message. By dedicating a port to SOAP without tunneling, the firewall only has to worry about one thing passing over that port. Moving your HTTP server to port 8080 but still accepting SOAP connections over it doesn't solve this problem.

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I wanted to explore how Perl's closures can be manipulated, and ended up creating an object system by accident.
-- Schemer

Note: All code is untested, unless otherwise stated