| 摘要 |
PROBLEM TO BE SOLVED: To hold the quality of communication and to improve security by dynamically changing common cryptographic keys without interrupting communication between a transmitting side and a receiving side. SOLUTION: Four cryptographic keys shared by an access point 2 and respective stations 3a, 3b,... are set up and two of the four cryptographic keys are used for respective communication. Two of four cryptographic keys are successively changed as groups to change the cryptographic keys without interrupting communication. Namely the access point 2 changes one group of cryptographic keys being practically used out of four cryptographic keys to the other group at each fixed time, updates cryptographic keys which are not used and periodically distributes the updated cryptographic keys to each of the connected stations 3a, 3b,.... When the cryptographic keys are distributed from the access point, each of the stations 3a, 3b,... changes a transmitting cryptographic key to the distributed cryptographic key to communicate with the access point 2. COPYRIGHT: (C)2004,JPO
|
