BO-Multicast: Boolean Operation Multicast * ShinHyoung Lee, SeeHwan Yoo, SangSun Byun, and Chuck Yoo Computer Science & Engineering, Korea University Seoul, Korea tshlee, shyoo, ssbyun, hxy}(@os.korea.ac.kr Abstract-Multicast is a multiuser communication scheme. Till This paper proposes an extension of supporting boolean now, multicast has been studied to handle one multicast group at a operations between multicast groups named BO-Multicast and time. However new applications such as online games need to handle multiple groups simultaneously. This paper proposes BO- owgthe performan rests Ti remainderiftistpapes Multicast; Boolean operation multicast. Through NS2 simulation, organized as follows. In section 2, we explain existing studies we show that Boolean operations can improve the performance by on managing multiple multicast groups, namely GCM [3] and 610 percent in delay and 210 percent in routing table size. CMS [11]. In section 3, we define the boolean operation for multicast groups. Besides, we describe the mechanism of the I. INTRODUCTION boolean operations and show the option-field of IP-header Multicasting provides an efficient way of disseminating data designed for. In Section 4, the result of the simulation is from sender to a group of receivers. Instead of sending a presented. The result of the simulation of the delay covers the separate copy of the data to each individual receiver, the sender receiving multicast packets and the numbers of the routing just sends a single copy to all the receivers so that network table of the router caused by making lots of groups. resource can be saved. Many applications are natural Conclusions and future work are in section 5. candidates for using multicast, e.g., distributed databases [17], II. RELATED WORKS replicated file systems [18], resource allocation in distributed systms 2], istibutd poces maageent 12] disribted The existing study for the operation of multicast groups has games [14], and teleconferencing [10]. been mostly studied [3], [7], [9], [11], [13], [15], [16]. GCM gamost exiing multcast grucmnag e n1c s was intended to use multicast with the support of varied Most existing multicast group management [1] schemes have oprtnsbwenheGMgusadsb-op.GC hs concentrated on one group. In other words, data is multicasted opra in tw te GCM group and sub-roups. CMS to one group at a time. However new applications such as .gC an tonprote tGcM groupfn multiplayer online games use a large number of multicast m rg n v man ica st Grus groups simultaneously, which brings up new issues.A.GopCmuiaonMdtr(C) grup imltnouly hihbrng p ewisus GCM exists over the network layer. GCM provides IP Assume there are two multicast groups A and B. If data GMeit vrtentoklyr C rvdsI needs to be multicasted to nodes that belong to both A and B multicast like service and inter GCM group operations. However GCM is not pure IP multicast because it is not the together, under the current multicasting scheme, a new network layer service. multicast group has to be created, and the nodes have to GCM supports inter GCM group operation in GCM domain. (re)join the new multicast group after leaving A and B GCM domain is a network domain which serves GCM service. respectively. Also suppose data is multicasted to A and B GCM group is not informed outside of GCM domain. simultaneously. Then, nodes that belong to both A and B will receive two identical copies of the data. GCM doma This is because data can be multicasted to only one group at a time, which leads to the overhead of leaving and rejoining CGM group 1 GCM group 2 multicast groups and to the overloading of the network bandwidth. This inefficiency can be avoided if the current multicast scheme is extended to handle multiple multicast groups. sub-group This research was supported by the MIC(Ministry of Information and Communication), Korea, under the ITRC(lnformation Technology I GCM serverl Research Center) support program supervised by the IITA(Institute of Information Technology Assessment) Figure 1. GCM groups in GCM domain I1-4244-0574-2/06/$20.00 (0)2006 I EEE