KEY MANAGEMENT COMMUNICATION DEVICE AND KEY DISTRIBUTION METHOD

摘要

PROBLEM TO BE SOLVED: To provide a key management communication device and a key distribution method that can efficiently re-distribute a key when abnormality occurs in a key used commonly in a network.SOLUTION: A key distribution part 13 distributes a communication key used commonly among communication devices connected to a network through the network to the communication devices connected to the network. A key state management part 14 manages the state of the distributed communication key. A key distribution part 13 selects, according to a predetermined condition, whether a communication key is re-distributed to a communication device which does not normally hold the communication key or a new communication key is concurrently distributed to the communication devices connected to the network when abnormality occurs in the state of the communication key.SELECTED DRAWING: Figure 2