1. one-way hash function Or "message digest function" A one-way function which takes a variable-length message and produces a fixed-length hash. Given the hash it is computationally infeasible to find a message with that hash; in fact one cant determine any usable information about a message with that hash, not even a single bit. For some one-way hash functions its also computationally impossible to determine two messages which produce the same hash. A one-way hash function can be private or public, just like an encryption function. MD5, SHA and Snefru are examples public one-way hash functions. A public one-way hash function can be used to speed up a public-key digital signature system. Rather than sign a long message, which can take a long time, compute the one-way hash of the message, and sign the hash. sci. crypt FAQ ftp://src. doc. ic. ac. uk/usenet/usenet-by-group/sci. crypt/.
one-way hash function |
