In this paper we address the problem of secure multicast of data
streams over a multihop wireless ad hoc network. We propose a key
management protocol that aims at solving problems that are specific to
ad hoc networks such as mobility, unreliable links, and multihop
communication cost. The main idea is to have group members actively
participate to the multicast group security therefore reducing the
communication and computation load on the source. We also extend the
proposed basic secure multicast tree using multi-link capability
combined with a k-out-of-N coding approac. Since the group security is
distributed among the group members we propose a service right
certificate to verify that a node is authorized to join the group and
also corresponding revocation mechanism. We simulated our protocol
within the ns-2 environment under various mobility, group size, and
group dynamic scenarios. Our preliminary simulation results indicate
that the communication cost and join delay of the protocol scale well
when the group size and nodes mobility increase.