2DMAC: A Sustainable and Efficient Medium Access Control Mechanism for Future Wireless NoCs

Abstract

Wireless Network-on-Chip (WNoC) requires a Medium Access Control (MAC) mechanism for an interference-free sharing of the wireless channel. In traditional MAC, a token is circulated among the Wireless Interfaces (WIs) in a Round Robin manner. The WI with the token holds the channel for a fixed number of cycles. However, the channel requirement of the individual WIs dynamically changes over time due to the varying traffic density across the WNoC. Moreover, the conventional WNoCs give equal importance to all the traffic taking the wireless path and transmit it in an oldest-first manner. Nevertheless, the critical data can degrade the system performance to a large extent by delaying the application runtime if not served promptly. We propose 2DMAC, which can change the token arbitration pattern and tune the channel hold time of each WI based on its runtime traffic density and criticality status. Moreover, 2DMAC prioritizes the critical traffic over the non-critical traffic during the wireless data transfer. The proposed mechanism improves the wireless channel utilization by 15.67% and the network throughput by 29.83% and reduces the critical data latency by 29.77% over the traditional MAC.