Multicast routing algorithms and protocols: a tutorial

Abstract

Multicasting is the ability of a communication network to accept a single message from an application and to deliver copies of the message to multiple recipients at different locations. Recentlv. there has been an exolosion of research literature on < .multicast communication. This ulticasling is the ability of a communication network to acccpt a single message from an application and to dclivcr copies of the mcssagc to multiple recipients at different locations. One of the cliallcngcs is to minimize tho amount of network resources employcd by multicasting. To illustrate this point, k t us assume that a vidco server wants to transmit a movie to 1000 recipients ( Fig. l a ) . If the server wcre to cmploy 1000 scparate point-to-point connections (e.g., TCP connections), 1000 copies of the movie may have ti) be sent over a singlc link, thus making poor usc of the availablc bandwidth. An efficient implementation of multicasting permits much bettcr nsc of the availeblc bandwidth by transmitting at most onc copy of the movic on cach link in the nctwork, as shown in Fig. lb. Rcccntly, there has bccn a lot of research in the area of multicast communication. Although many excellent surveys and books cxist which cxamine varions aspccts of multicasting [I-61, i n thc course of our studies wc have found a need for a tutorial-cum-survcy of the various multicast routing algorithms and their relationship with mnlticast routing protocols. In this work we present a tutorial-cum-survcy of the following two important topics in multicasting:-Multicast routing algorithms * Multicast routing protocols Communication networks can be classificd into two categories: local area networks (LANs) and wide area nctworks (WANs). A LAN spans a small geographical area, typically a single building or a cluster of buildings, while a WAN spans a large geographical area (e.g., a nation). Often, nodes connccted to a LAN communicatc over a broadcast network, while nodes connected to a WAN communicate via a switched network. In a broadcast LAN, a transmission from any one node is received by all the nodes on the network; thus, multicasting is easily implementThis work has heor supporied inpar( />y ike Nalional Suie,rce Foundution (NSF) under G,owts Nos. NCR 9508238 nnd ANI-9XO52U5. . _ I u&"g a movie" 1000 di&ent users; b) multicasting the movie. (R= slandard router, MR= rnullicast router.) 90 ox~o-xn4~~nn1~io.oo o 2uuo IEEE IEEE Network * JanuaryiFebrualy 2000

A survey of multicasting protocols for broadcast-and-select single-hop networks

“…The goal of algorithm is to schedule as many destinations as possible to receive the multicast packet in each transmission trial. The MDSA operates in two modes, the initial mode and the maximum mode 4 . It simply starts scheduling the multicast packet in the initial mode by finding the earliest time slot at which the multicast packet can be scheduled.…”

“…The second algorithm uses the single packet transmission approach and it delivers the multicast packet to all the receivers in one time slot, and is therefore called the no-partition algorithm. Based on the simulation results, the authors observed that the MDSA achieves lower 4 These names are given for the sake of explaning the operation on the MDSA only and they were not used in [28] packet delay than both the greedy and the no-partitioning algorithms.…”

“…Many excellent and comprehensive survey papers and monographs exist which treat the various aspects of multicasting at large [4] [5].…”

Multicast routing and wavelength assignment in WDM networks with limited drop-offs

“…Multicast is a point-to-multipoint communication that a node sends data to multiple destinations [4,13]. There are many multicast applications, such as news feeds, video distribution, multimedia conferencing, and so on.…”

“…There are many multicast applications, such as news feeds, video distribution, multimedia conferencing, and so on. It is a challenging job to implement multicast in Wide Area Networks (WANs) due to high complexity of multicast routing [10,13]. Multicast routing is to find a tree rooted from the source and connecting all the destinations.…”