Point-to-multipoint communication protocol PTMP and evaluation of its performance

In this paper, an efficient one-way point-to-multipoint communication protocol PMTP is proposed. The PTM protocol is helpful in distribution unique information content to many workstations simultaneously and correctly. The protocol is designed for network channels of low error possibility and utilizes broadcast for the stream-type data distribution. Re-transmission request for lost packets are returned to the server, while acknowledgements for correctly received packets are not returned to the server. The performances of PTMP is about twice that of an isolated one-connection TCP/IP, and not degraded up to 40 clients. We have applied the protocol to a network presentation system which requires stream-type data communication. The network presentation system is intended to display the same graphical images at multiple workstations simultaneously on the X window system. With the PTM protocol, the system performance is improved and the use of the network bandwidth is lowered.