DSMCast: a scalable approach for DiffServ multicasting

One of the dominant questions facing the Internet today is, how can the network meet the needs of the users and their applications (QoS) while trying to keep such implementations scalable to the billions of users present on the Internet? Two of the emerging technologies for answering this question are Differentiated Services (DiffServ) and multicasting. Although both are complementary technologies, the integration of the two technologies is a non-trivial task due to architectural conflicts between multicasting and DiffServ. In this paper, we first investigate viable approaches for DiffServ multicasting and then propose an efficient approach, called DSMCast, for multicasting across an individual DiffServ domain that is scalable in terms of group size, network size, and number of groups. In addition, we propose a protocol for member join/leave and detail our protocol for both SSM (Source-Specific Multicast) and traditional IP multicasting. Finally, we present simulation studies of the DSMCast architecture comparing it with alternate approaches and offer conclusions regarding our work.