Patent ID: 8588423

Claim:
A group/multicast key distribution method based upon a unicast session key, comprising: constructing, by a base station, a group/multicast key distribution packet; and broadcasting, by the base station, the group/multicast key distribution packet to all of terminals which have passed authentication for security, wherein the distribution method further comprise: before the base station constructs the group/multicast key distribution packet, defining, by the base station, system parameters including two p-order cyclic groups of (G 1 , +) and (G 2 , •) with p being a prime number and Diffie-Hellman calculation issue being a difficult issue in G 1 , P representing a generator of G 1 , e representing bilinear transformation on G 1 and G 2 , i.e., e:G 1 ×G 1 →G 2 , and h(•) representing a unidirectional hash function.