On Improving Throughput and Latency of MESH Interconnection Networks

Abstract

The primary components of digital system comprise of processing elements and memory units and interconnection networksare used to connect these components. With recent advancements in technology,it has become imperative to explore the high-speed interconnection networks due to the progress in the domains of processor and memory units. Initially, the bus-based architecture was used to connect the various nodes, however,with the increase in number of nodes, these buses became a bottleneck; and therefore, the dedicated buses were used. Regardless, the usage of large number of dedicated buses led to an increase in the mesh of wires, which created complexity in the implementation of the network. The idea of routing packetswas hence initiated for the development of the mesh topology based on tile architecture. Again, this topology went through a large number of variants, yet most of them tried to reduce the diameter by introducing lengthy links on the topology, thus affecting the scalability of the topology. The diagonal (toroidal) mesh has long links and gets disconnected for an even number of nodes.Due to this,a modified diagonal mesh interconnection network is introduced in this research, which uses horizontal and vertical links on outer edges in place of toroidal links. This idea removes the drawback of the topology and determines that the diameter can only represent the upper bound of the distance. Further, the shuffle exchange network, introduced to the modified diagonal mesh interconnection networks, helped in reducing the average internode distance. The results pertaining to the proposed topology are compared with the torus topology. Apart from torus topology,another topology that reduces toroidal links via the combination of diagonal connected mesh and T-mesh topology is compared with the proposed work. The results revealed that the suggested topology performs better than the existing two topologies. For increasing the scalability, the toroidal links must be placed in an optimal manner.