| 摘要 |
A method for performing encryption communications in a communication system is provided to increase system efficiency by performing a key agreement with information used in a SIP(Session Initiation Protocol) message signature. A first client generates a first message for requesting encryption communications and a plurality of parameters used in a first signature(301, 303), generates a first session key for performing the encryption communications(305), generates the first signature after encrypting the first message(307, 309), and transmits an encrypted first message and the first signature to a second client(311). The second client determines validity of the encrypted first message and the first signature, generates a plurality of parameters used in a second message and a second signature, generates a second session key, generates the second signature after encrypting the second message, and transmits an encrypted second message and second message to the first client. |
