> If you email files to a client, you have actual proof that the files were > indeed sent to the client. If you give them a link, and they have to > download the files themselves, then you don't really have proof that they > have their hands on the files.
I think this depends on what the definition of "client" is. If the definition includes the first smtp gateway that is outside the sending company then sure, there is proof. The distinction is: I can prove that the company owning smtp host blah.example.com accepted this message but I can't prove that example.com employee foo received it or that an attachment wasn't corrupted, etc... And this might be good enough in many business cases. On the other hand, when a file is downloaded from a simple http server, there is a very good chance that there is a log showing the client's IP address, time of request, a value which shows if the request was answered, that client's operating system, browser version and even patch level. There is still no guarantee of the clients successful transfer. Beware the connectionless protocol... If a file transfer really matters and cost is an issue, FTP/SCP is the way to go. There are also the proprietary (expensive) solutions mentioned earlier which I imagine include extensive logging facilities. ~JasonG ~ Ninja Email Security with Cloudmark Spam Engine Gets Image Spam ~ ~ http://www.sunbeltsoftware.com/Ninja ~