Performance evaluation of priority CSMA-CA mechanism on ISA100.11a wireless network

The International Society of Automation recently released ISA100.11a as an open standard for reliable wireless networks for industrial automation. ISA100.11a uses the TDMA scheme in the medium access layer to provide deterministic services. However, ISA100.11a adopts the CSMA-CA mechanism with priorities for retransmission from failure on dedicated links, sporadic data, and network configuration.This paper evaluates ISA100.11a CSMA-CA by simulation, considering the effects of backoff procedures and priority settings to probability of collision and successful use of slots. It's demonstrated that a high number of priority classes enable better network utilization resulting in less number of packets exceeding their lifetime.

Research highlights
► Performance of CSMA-CA at ISA100.11a is evaluated with OPNET.
► ISA100.11a CSMA is for retransmission, sporadic data, and network configuration.
► Without priority setting, ISA100.11a CSMA uses bandwidth up to 35% as slotted ALOHA.
► Priority setting leads to higher bandwidth using, lower average end-to-end delay.