As the major problem in multicast security, the group key management has beenthe focus of research. But few results are satisfactory. In this paper, the problems of group keymanagement and access control for large dynamic multicast group have been researched and asolution based on SubGroup Secure Controllers (SGSCs) is presented, which solves many problemsin IOLUS system and WGL scheme. As the major problem in multicast security, the group key management has beenthe focus of research. In this paper, the problems of group keymanagement and access control for large dynamic multicast group have been researched and as based on SubGroup Secure Controllers (SGSCs) is presented, which solves many problems in IOLUS system and WGL scheme.