| 摘要 |
A key management method for broadcast encryption in a tree topology network which includes a plurality of nodes is provided. The method includes forming a plurality of first node groups each of which includes a node at a second layer and nodes, which belong to the node at the second layer, at a first layer in the tree topology network; forming a plurality of second node groups each of which includes a node at a third layer, at least one node which belongs to the node at the third layer, and at least one node which belongs to the node at the third layer and which forms one of the first node groups, in the tree topology; assigning a plurality of first keys which are shared by subsets of the nodes of the first node groups at the first layer, to each of the first node groups, respectively; assigning a plurality of second keys which are shared by subsets of the nodes of the second node groups at the second layer, to each of the second node groups, respectively; and transmitting an update key which is encrypted using at least one key of either the plurality of first keys or the plurality of second keys.
|
