If multicast communication appears as the most efficient way to send data to a group of participants, it presents also more vulnerabilities to attacks and requires services such as authentication, integrity and confidentiality to transport data securely. In this paper, after introducing the research work related to securing multicast communication, we present the protocol Baal1 as a solution to the scalability problems of key management in dynamic multicast group and show how Baal resolves the user’s revocation problem. This protocol is based on distributed group key management by local controllers within sub-networks.