Research On Congestion Control And Link Fault Tolerance Technology In WiNoC

Wireless Network-on-Chip(WiNoC)is a novel architectural design in an on-chip multi-core system that uses a CMOS-compatible wireless emerging technology to provide a scalable,energy-efficient,and low-latency network.The wireless on-chip network has become a very promising interconnection method,and realizes efficient long-distance single-hop communication through the wireless interface integrated by the router.As the core component of wireless communication in the network,the wireless router bears a large amount of data traffic.If congestion occurs,the network performance will be seriously affected.At the same time,due to the immature wireless integration technology at this stage,the wireless on-chip network system is susceptible to high failure rate and reduces the reliability of the network.Therefore,a network with congestion control and fault tolerance can greatly improve the reliability of the system.In this thesis,the congestion problem and link fault tolerance method in the wireless on-chip network are deeply studied.(1)As the key component of wireless communication on WiNoC,wireless router will seriously affect the network performance when congestion occurs.Thus,a high-performance wireless router design scheme deploying cooperative congestion control capacity(C~3WR)is proposed.To relieve buffer congestion happened at the receiving end of the wireless interface,a scheme that the wireless input port is connected to other local input buffer is designed to provide multipath transmission for the congested data.Then a WCC algorithm is proposed to mitigate wireless receiver congestion by shunting packets.For the buffer congestion in the sender side of the wireless interface,a dynamic routing policy is adopted to reduce the traffic injection rate of the congested wireless router.Experimental results show that compared with the comparison object at different injection rates,the scheme greatly improves the network throughput and effectively reduces the network delay.The scheme balances network traffic distribution in a coordinated congestion control manner,ensuring system performance and making full use of available resources.(2)WiNoC has become a promising on-chip interconnect architecture.Due to the integration and manufacturing limits of wireless interconnects in nanotechnology,WiNoC systems are more susceptible to high failure rates.In this thesis,we propose a novel fault-tolerant routing algorithm based on regional fault-aware techniques for link failures in WiNoC.The algorithm is based on a novel mode of transmission of regional fault levels.We fuse congestion control mechanism with this algorithm to mitigate the adverse effect of failures and balance network load.Moreover,combining the advantage of 2-hop awareness,a fine trade-off between overhead and performance is achieved.Simulation results demonstrate that compared with the traditional counterpart,the performance benefits clearly overweigh the overhead with acceptable area increase.The newly proposed routing algorithm significantly enhances the robustness of the system.