Patent ID: 7917748

Claim:
A communication system comprising: at least one server; and a plurality of groups of nodes communicating with said at least one server, each node having a user associated therewith, respective nodes within a given group communicating with each other and encrypting traffic therebetween based upon a group traffic key; said at least one server configured to generate for each given node a corresponding user group record comprising at least one group key for at least one group that the given node is a member thereof, receive a user generated user key from the given node and verify the user of the given node using the user generated user key, determine if a stored encrypted user group record at the given node is current, if the user is verified and the stored encrypted user group record is out of date, then encrypt the corresponding user group record based upon a respective user key for the given node, and transmit the encrypted user group record to the given node, and encrypt, for each group, the group traffic key based upon a respective group key and transmit the encrypted group traffic key to nodes being a member of the respective group; the given node configured to decrypt the encrypted user group record for accessing the at least one group key, and to decrypt the encrypted group traffic key based upon the at least one group key.