Patent ID: 8050209

Claim:
A group communication method for realizing communication in a group including communication devices by using a management device managing the group, the method comprising: receiving an enrollment message from at least two communication devices; grouping the at least two communication devices transmitting the enrollment message; creating a first group key including first data and second data, which specifies the at least two grouped communication devices as a same subgroup, based on address information of the at least communication devices included in the enrollment message; transmitting the first group key to the at least two grouped communication devices of the same subgroup; receiving the first group key at the grouped communication devices; selecting a communication device of the at least two grouped communication devices as a destination of distribution data to receive the distribution data for the at least two grouped communication devices; transmitting the distribution data including a MAC address of the selected communication device as a destination and a second group key including third data resulted from an exclusive OR operation of the first data and the second data, to the grouped communication devices including the selected communication device; receiving the distribution data at the selected communication device; recognizing the distribution data at the grouped communication devices except the selected communication device, each of which has a MAC address different from the MAC address included in the distribution data, and determining to receive the distribution data when a result of the exclusive OR operation of the first data and the second data included in the first group key matches the third data included in the second group key; and receiving, at the grouped communication devices except the selected communication device, the distribution data upon determining to receive the distinction data.