摘要 |
A method for deriving past keys by using a one way function to relate an ordered sequence of keys to each other. The key generation works by taking the current key and performing a one-way hash function to produce a previous key (2). The hash process is repeated until the number of desired keys (3, 4, 5) is reached. A user is able to derive past keys a key but unable to derive future keys because one-way function are not reversible. |