Protecting the privacy of you computer files...

(Also available: an updated, expanded version of this.)

There are many programs available to encrypt your files. This isn't about that! Whether you use a special program, or simply the 'password protect' option provided with good applications like Quattro and AmiPro, you are faced with the problem of choosing (and remembering!!) a password. (Where the encryption is used to protect a file in transit, there is also the problem of letting the recipient (only!) know what the password is.

Here is a simple idea which overcomes some of the problems of using passwords. Call your file anything you like, as long as you leave me the last three characters of the first part of the name. For example, if you want to call something PHONES.TXT, that's fine.

For an example, let's give the file the password ursdaesday. How on earth are you supposed to remember that? I want to use 'my' three characters as follows. The file would be saved as PHONES423.TXT. The 423 tells me that the password is made from parts of 'thursday' (4th day of week) and 'tuesday'. I always take 5 characters from each. I started (this time) with the 3rd letter in each name, and 'told' myself that was the rule with the last character in my code.

Now you have a way to 'mark' your files with an indication of the password which will unlock them. If you send things to other people across the net, you can tell them the system and they will know the password from the file's name.

For more critical missions, you can extend the system. Use letters instead of numbers, so 'dce' would mean use the 4th (d is 4th letter) and 3rd starting points, start at the 5th point within each. For such a system, a book with pages 1-26 marked 'a' to 'z' would be helpful. The third character could be interpreted as 'Use the first word on the nth (5th in example) line.'

I hope the ideas above are of interest or use. (A quick email would be welcome if so.) I have ideas for a more complex, more secure system of 'locking' files based on 'one time pads' stored on floppy discs. Let me know if you would be interested?...........