A Reliable Multicast Protocol, TRMP, for Data Acquisition Systems

A message passing used in a data acquisition system is mainly developed on the computer network because of its high connectivity, usability, and maintainability. Most of the data acquisition system is developed in the application layer of TCP/IP protocol and on the TCP protocol, in general, which is a highly reliable protocol. The protocol works well for a general data transfer such as one-to-one transfer. The data acquisition traffic is, however, not only one-to-one but also one-to-many traffic. In latter case, the transmission node should transmit only one datum to many nodes with a multicast method. It is one of important communication methods also for the data acquisition system. Though it is very useful, the base protocol of the multicast method is UDP, which doesn´t provide a reliable communication. We have, therefore, developed the reliable multicast protocol, TRMP, in the transport layer for a highly reliable multicast communication. The protocol overhead of multicast communication with the new protocol TRMP has been also decreased in comparison with multiple data transmission with a multiple TCP connections.