GROUP REGISTRATION DEVICE, GROUP REGISTRATION RELEASE DEVICE, GROUP REGISTRATION METHOD, LICENSE ACQUISITION DEVICE, LICENSE ACQUISITION METHOD, TIME SETTING DEVICE, AND TIME SETTING METHOD

摘要

There is provided a group registration device or the like which is capable of simplifying registration processing to readily perform group registration while retaining secure registration processing. A group registration device 10 includes a registration request detecting unit, a session ID generating unit for generating a session ID, a registration request message sending unit, a registration reply message receiving unit, a verification unit 231 for verifying non-redundancy of a message, and a storage unit 241 for storing an ID list included in a registration reply message in a storage region so as to be associated with a group ID. Within the same registration session, the registration request message is sent once, the registration reply message is received once, and processing is restricted to sending of the registration request message and receiving of the registration reply message.