Performance of FQDB, a fair MAC protocol for dual bus networks

The authors present the delay-throughput performance of a new MAC protocol, the fair queue dual bus (FQDB), which relieves dual bus networks from the unfairness problems exhibited by the basic version of the distributed queue dual bus (DQDB) standard. The protocol considered is absolutely fair in bandwidth sharing and does not imply any change in the DQDB transmission system. It retains all the positive features of DQDB including simplicity, robustness, flexibility, 100% bandwidth utilization, and little slot access delay at light load. Comparisons to DQDB with the bandwidth balancing mechanism show that the FQDB delay-throughput performance was always superior while its implementation complexity was comparable