Experimental system for computer network via satellite /CS/. II - Communication protocols

The communication protocols of an experimental system for computer network via communication satellite are given. The network is of the centralized type and consists of one center station and many small user stations. Messages are exchanged only between the center station and the user stations. Three levels of communication protocols are defined for the network communication: the physical level, the burst level, and the link level; the latter two are discussed. The burst level protocol defines the burst format and five access schemes: the slotted ALOHA scheme, the one-channel slot reservation scheme, the two-channel slot reservation scheme, the TDMA scheme, and the composite scheme. The link level protocol defines the data link control procedures based on HDLC. Due to the long delay time of the satellite channel, some optional functions in HDLC were adopted.