You could actually use javascript to provide client-side decription of the whole document and encription of the data to send back to the server.
A quick search pointed me to this implementation of DES in javascript. This is a symmetric cypher, which means both the server and the client must have a previously agreed-on key. The whole thing could also work transparently to the user if he put a javascript setting file in some local directory. This way, the encripted document could include the file via the <script src="..."> tag and use its contents (unless browsers decide to stop such behaviour).
I am not a real fan of javascript, after the compatibility nightmares I had to go through, but you have a chance to set-up something most evolved browsers support and use this as a filter on outgoing docs and incoming data on your server without having to reengineer your application.

Best regards

Antonio Bellezza

In reply to Re: Safely Transferring Information on the Internet by abell
in thread Safely Transferring Information on the Internet by Nemp

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