Shortest-path Routing in Homogeneous Point-to-Point Networks With Virtual Cut-Through Switching

Much research in recent years has focused on various routing strategies for supporting ee-cient communication in point-to-point networks. Other research has emphasized novel switching techniques, such as virtual cut-through and wormhole switching. However, little attention has been paid to the subtle interplay between routing and switching schemes. It is desirable to select routing strategies that best exploit the chosen switching scheme. In particular, this paper presents an analysis of various shortest-path routing strategies in wrapped meshes, in the context of virtual cut-through switching. Routing strategies are compared, based on the cut-through probability and the packet delivery-time distribution, using both analytical mod-eling and simulation. Adaptive routing schemes that can dynamically select from multiple shortest-path links are shown to best capitalize on cut-through switching, particularly in the presence of \hot-spot" network traac. Simulation results illustrate how inter-node dependencies impact the cut-through probability and packet delivery time. Implementation details are also discussed.