| 摘要 |
PURPOSE: A method for exchanging a group share key is provided to reduce the storage load of a device and communication load by providing the device information of a group only when a communication group is composed. CONSTITUTION: An information message is transmitted to a server (S10). A server information message is transmitted to the communication device of a communication group (S20). A communication device information message is transmitted to the server (S30). A pre-information message is transmitted to a first device and the communication device (S40). A key exchange message is transmitted to a server (S50). A key exchange-confirming message is transmitted to the first device and the communication device (S60). A share key is generated (S70). [Reference numerals] (AA) First device; (BB) Server; (CC) Communication device; (S10) First device information message; (S20) Server information message; (S30) Communication device information message; (S40) Preparatory information message; (S50) Key exchange message; (S60) Key exchange confirmation message; (S70) Generate a shear key |
