HYBRID ACCESS-CONTROL FOR BROADCAST-BASED ATM-LANS

This paper proposes a hybrid access control scheme for broadcast-based ATM-LANs. Broadcast-based ATM-LANs are shared media networks with star topology. In this network, packets are broadcast to all subscriber terminals by a CPYF (Cell coPY Function) node located in the ATM network and only relevant packets are extracted and sent to the destined user layer function by packet filtering functions in the terminals. The simplicity of the packet transfer mechanism makes the network very economical. In broadcast-based ATM-LANs, the hybrid access control scheme is effective in improving performance. In this scheme, short packets and long packets are transmitted respectively by means of a back-pressure type and a CSMA/CD type access control scheme. Throughput evaluation was performed by computer simulation and the results show that the proposed scheme achieves a high throughput characteristic.