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Performance evaluation of multicast overlay routing protocols

Stachowiak K., Pawlak T., Piechowiak M.

Image Processing & Communications

2012

Vol. 17, no. 1-2

19--31

For almost three decades the multicast communication has been a subject of a dynamic research. It came to the world of the packet switching networks rather late and still has not becorne a fist class citizen of the Internet, yet the demand for such services is growing and thus the relevant technologies evolve persistently providing increasing quality and availability of the means of the group communication. The overlay approach to the multicast is an application layer realization which came to life due to certain deficiencies at the lower layers. In general the gain from using multicast for group communication instead of duplicated unicast links is that we avoid sending the same data many times through a single link. Such gain may he achieved with the use of the router level mulitcast solution. The overlay solutions tend to approach his level of efficiency with a different degree of success. Therefore one of the main characteristics that is interesting when evaluating a particular overlay protocol- is how well does it achieve the aforementioned gain. There are several metrics that allow for objective comparison of protocols in this regard. However this is not the only point of view to provide a valuable evaluation of the multicast overlay solutions. One of the important as aspects of the modem group communication such as the IPTV or teleconferencing is the dynamic nature of the users' participation. A particular group may be joined and left by multiple users at a very frequent rate which is critical to the resources management as well as to maintaining the integrity of the abstract communication structure, e.g. a tree spanning all the participants. In such case two major classes of the evaluation criteria emerge: the statical and the dynamical ones. They're both very important and interdependent, however the means to measure them may differ significantly. In this article a wide variety of the multicast overlay protocols have been analysed and two of them have been chosen to be compared. The stress of the evaluation has heen put on the dynamic aspects of the multicast overlay protocols operation.

Enhancing Data Transmission Reliability with Multipath Multicast Rate Allocation

Bagherpour M., Alipour M., Kure Ø.

Advances in Electronics and Telecommunications

2011

Vol. 2, no. 3

61--70

In this paper, a multipath routing scheme is proposed for data transmission in a packet-switched network to improve the reliability of data delivery to multicast destinations, and to reduce network congestion. A multi-objective optimization model is presented that utilizes FEC (Forward Error Correction) across multiple multicast trees for transmitting packets toward the destinations. This model assigns the transmission rates over multicast trees so that the probability of irrecoverable loss for each destination and also the link congestion are minimized. We propose a genetic algorithm based on SPEA (Strength Pareto Evolutionary Algorithm) in order to approximate Pareto optimal solutions of this rate allocation problem with a nondominated solution set. Numerical results show that splitting data packets between multiple trees increases reliability and decreases network congestion when compared with the results obtained for transmitting data packets over a single tree.