Cryptographic communication between communication terminals can be realized even when a plurality of cryptographic algorithms are present, and secure cryptographic communication for a longer time is realized without increasing a processing overhead at each of the communication terminals. A key management server manages cryptographic algorithms that can be used by each of the communication terminal, and searches for a cryptographic algorithm common to the communication terminals, and notifies each of the communication terminals of the cryptographic algorithm found by the search together with plural key generation informations, each piece containing a key to be used in the cryptographic algorithm or a key type for generating the key. Each of the communication terminals sequentially switches the plural key generation informations notified from the key management server, and performs the cryptographic communication with a communication counterpart in accordance with the cryptographic algorithm notified from the key management server.

 
Web www.patentalert.com

< Method of delivering Direct Proof private keys to devices using an on-line service

> Quantum cryptography with multi-party randomness

> Synchronizing the exchange of cryptography information between kernel drivers

~ 00596