20140325225 | Self-authenticated method with timestamp - A self-authenticated method with timestamp consists of key generating process and self-authenticated process between sender and receiver. The key generating center generates public key generator and private key according to sender's ID; combines the ID of the key generating center and the applied valid time of the sender to generate a identity of the key generating center with timestamp, and generating the corresponding coupled public and private keys; encrypting sender's ID and timestamp by using the private key of the coupled public and private keys, and obtains the first ciphertext of the sender's ID valid period; key generating center packs the sender's valid period, ID plaintext, first ciphertext of ID valid period, sender's public key generator and private key as a tool kit, and send the tool kit key to the sender; the sender encrypts its own ID and valid period by using sender's private key, to form the second ciphertext of the ID valid period, then sends the plaintext of the valid period, the second ciphertext and the first ciphertext of the ID valid period to the receiver; at the same time, performs valid period authentication and identity authentication. The present invention solves the problem in the existing self-authenticated system that the system cannot define valid period of a user's key. | 10-30-2014 |