A new framework or the creation and management of subgroups within a larger multicast group to enforce information flow policies according to the Bell-LaPedula Confidentiality Model is proposed. The framework utilizes hierarchical key management trees to provide the necessary keying infrastructure. It also integrates the concepts of distributed key management with key translators to provide a more scalable solution for large, dynamic multicast groups. Unlike most of the existing work, this framework supports both one-to-many and many-to-many multicast groups. In addition, it supports inter-domain multicast groups and limits the effects of group membership changes to the domain(s) with affected members.