Evaluation of a Causal Order Protocol in Broadcast Channel.

Group and multicast communication provide basic functions for many applications in distributed computing. In such a communication, the causal ordering property among messages should hold throughout distributed sites. Several communication protocols for this purpose have been designed so far. They are designed mostly under the strong assumptions: there is no loss of messages in the communication channel or the order of the messages is preserved or both. However, in WAN environment, it is desirable to design such a protocol without assuming these conditions from the efficiency point of view. In this paper, a protocol which provides the causal ordered broadcast in a non-FIFO network is investigated. The non-FIFO network is defined as the network in which there exists possibilities of loss and disorder of messages. The purpose of this paper is to perform experimental evaluations to a causal ordering protocol which is specially designed for a non-FIFO network. The protocol is implemented as a software system, and the performance evaluation of the system is done by experiments. In addition, a simple approximation of the queue length of the system is proposed. The applicability of the approximation also is investigated. [ABSTRACT FROM AUTHOR]