Thanks to everyone for a really interesting and informative discussion group. I started out knowing almost nothing about encryption systems, and now I feel like I am at least an informed novice. I have learned a lot, and I really appreciate it. I will be in the Sangre de Christo Mtns. in New Mexico for the rest of the summer (w/o net access, this time), so I'll have to catch up in the fall. thanks again, -john