At 10:13 AM 10/9/96 -0800, Timothy C. May wrote:
Something ISPs could do--and may do if there is sufficient customer pressure--is to adopt a policy of "forward secrecy" (to slightly abuse this technical term). That is, to have an explicit policy--implemented in the software--of _really_ deleting the back messages once a customer downloads them to his site. This means that _backups_ must be done in a careful manner, such that even the backup tapes or disks are affected by a removal.
One technical approach is described in: "A Revocable Backup System", dabo@cs.princeton.edu (Dan Boneh) and rjl@cs.princeton.edu (Richard J. Lipton) in The 6th USENIX Security Symposium Proceedings. Basically the idea is to encrypt the file on the backup (tape) and then lose the encryption key when you want to "forget" the file. ------------------------------------------------------------------------- Bill Frantz | "Cave softly, cave safely, | Periwinkle -- Consulting (408)356-8506 | and cave with duct tape." | 16345 Englewood Ave. frantz@netcom.com | - Marianne Russo | Los Gatos, CA 95032, USA