| 摘要 |
A network communication system which can shorten processing time by selecting an adequate encryption method based on an encryption processing speed is provided. In the communication process, the client device determines whether the server device is in the same LAN or in WAN and whether the watermark such as "Confidential" is added to data. Then, based on these determination results, the client device extracts encryption methods from common key methods usable, and makes a list of encryption method candidates. The server device selects a common key method to be used to encrypt communication data from the notified list based on the communication speed and the encryption strength. The client device encrypts the communication data using the agreed common key method, and sends the encrypted data to the server device. Then, the server device decrypts the received encrypted data using the relevant common key method. |
