This strikes me as another variant on the venerable 'book' cypher. To quote Kahn (is that even close? The guy who wrote _The Code Breakers_.) 'What you gain in key size, you loose in key coherency.' In general book ciphers are not very strong. (At least thats what I think the big boys said...) But, speaking of random numbers. In Crypto '92 (or '93?) there is this great protocol for two players (Andy and Beth say) to listen to a poorly heard (radio) source (a low power satalite, or perhaps Radio Free Bosnia) and extract a shared secret key -- even when an evil opponent (Eve say) is listening with much better equipment. This is really a great result! It is at least as exciting as DH key exchange (to me). It's strength is based on probability and information theory and not on 'unproven' complexity theory assumtions (such as 'discrete logrithms are hard to compute'). But -- how do we make it work on the net? j' -- O I am Jay Prime Positive jpp@markv.com 1250 bit fingerprint B06229 = B8 95 E0 AF 9A A2 CD A5 89 C9 F0 FE B4 3A 2C 3F 524 bit fingerprint 2A915D = 8A 7C B9 F2 D5 46 4D ED 66 23 F1 71 DE FF 51 48 Public keys via `finger jpp@markv.com', or via email to pgp-public-keys@io.com Your feedback is welcome directly or via my symbol JPP on hex@sea.east.sun.com Resist the Clipper Chip, write "I oppose Clipper" to Clipper.petition@cpsr.org