On a related note. There's a program called term which is popular in the Linux community. from the latest term version announcement: (For those that don't know: Term is a user level slip replacement. It ISN'T slip, but achieves much of the functionality. Error correction, compression, and multiplexing across a serial line are all supported, enabling X windows across a serial line and such.. } Now, term already allows compression across the line (yes it has features for dealing with lines which can't handle certain characters). You can have several sessions going, file transfers and even X clients. I believe that it wouldn't take too much work to add DH key exchange and IDEA or triple DES? (GNU GMP might be a good place to look for the multiple precision math, but there are lots of choices). Am I going to do it? Well, not this week. If anyone has time to work on this, the term source is available by anon ftp from ftp tartarus.uwa.edu.au in /pub/oreillym/term. Last time I looked term would run on many popular Unix (or Unix-like) systems. Mark -- Mark Henderson markh@wimsey.bc.ca (personal account) RIPEM MD5OfPublicKey: F1F5F0C3984CBEAF3889ADAFA2437433 ViaCrypt PGP Key Fingerprint: 21 F6 AF 2B 6A 8A 0B E1 A1 2A 2A 06 4A D5 92 46 cryptography archive maintainer -- anon ftp -- wimsey.bc.ca:/pub/crypto