Dynamic behaviour of a new adaptive multiple-access protocol and comparison with the split-channel reservation multiple-access protocol

In the paper we discuss the dynamic behaviour of a new multiple-access protocol, the ALOHA-TDMA protocol, hereafter referred to as ATP-2. This protocol belongs to the category of the self-adaptive reservation multiple-access protocols. It uses two subchannels, the request subchannel for the user´s request packets and the information subchannel for their information packets, as in the split-channel reservation multiple-access (SRMA) protocol. The first channel (the request subchannel) operates with a fixed-access protocol (round-robin or random TDMA), whereas the second (the information subchannel) combines the advantages of the two basic multiple-access protocols, the S-ALOHA and the TDMA protocols. Thus, through the information contained in the reservation subchannel minislots, the ATP-2 can be smoothly adapted to the instantaneous service needs of the users. An analytical method is described to calculate the throughput, expected delay and some important probabilities. Also, the bistable behaviour of the ATP-2 protocol under certain operation conditions is examined. Next, a comparison is made between the ATP-2 and SRMA protocol that shows the superiority of the ATP-2. Finally, we propose a hardware implementation for the nodes of a network based on the ATP-2 protocol.