(IJACSA) International Journal of Advanced Computer Science and Applications, Vol. 2, No. 3, March 2011 Multicasting over Overlay Networks – A Critical Review M.F.M Firdhous Faculty of Information Technology, University of Moratuwa, Moratuwa, Sri Lanka.
[email protected] Abstract – Multicasting technology uses the minimum network internet due to the unnecessary congestion caused by resources to serve multiple clients by duplicating the data packets broadcast traffic that may bring the entire internet down in a at the closest possible point to the clients. This way at most only short time. one data packets travels down a network link at any one time irrespective of how many clients receive this packet. Traditionally Using the network layer multicast routers to create the multicasting has been implemented over a specialized network backbone of the internet is not that attractive as these routers built using multicast routers. This kind of network has the are more expensive compared to unicast routers. Also, the drawback of requiring the deployment of special routers that are absence of a multicast router at any point in the internet would more expensive than ordinary routers. Recently there is new defeat the objective of multicasting throughout the internet interest in delivering multicast traffic over application layer downstream from that point. Chu et al., have proposed to overlay networks. Application layer overlay networks though replace the multicast routers with peer to peer clients for built on top of the physical network, behave like an independent duplicating and forwarding the packets to downstream clients virtual network made up of only logical links between the nodes.