International Journal of Computer Applications
IPTV services delivered traditional television channels via IP to customers. IGMP protocol is the control mechanism used to control the delivery of multicast traffic to interested and authorized users. IGMP commands notify the upstream equipment to stop sending ("Leave") one channel or begin sending ("Join") another channel. Depending on the architectural choices, this process occurs in the DSLAM, an aggregation switch, or at an edge router. All channels are sent by a multicast source to DSLAM even if no user in the DSLAM has requested it. This leads to sub-optimal use of bandwidth.