Patent ID: 8850205

Claim:
A method of generating and distributing a key for encrypting and decrypting data in accordance with providing a service, the key being generated and distributed by an authentication server connected with wireless terminals through a communication network, the method comprising: obtaining characteristic information by decrypting encrypted characteristic information, the encrypted characteristic information having been received from each of n number of wireless terminals; generating a random key prior to a request for connection of a new wireless terminal to the authentication server; generating a group key configured to be used for encrypting and decrypting data in accordance with providing the service; generating using the authentication server a distribution key by using the random key, the group key and the characteristic information; transmitting the distribution key to each wireless terminal; upon connection of the new wireless terminal to the authentication server, obtaining characteristic information of the new wireless terminal by receiving and decrypting the encrypted characteristic information from the new wireless terminal; regenerating a random key; regenerating a distribution key using the regenerated random key, the characteristic information of the new wireless terminal, and the group key; and transmitting the regenerated distribution key to each wireless terminal.