Wavelength assignment for locally twisted cube communication pattern on optical bus network-on-chip

•We proposed a maximum m-induced subgraph of locally twisted cube.•An embedding scheme φφ for locally twisted cube on global bus topology is proposed.•We proved that the congestion is optimal under the embedding scheme φφ.•We proposed an optimal wavelength assignment which required 2n+13 wavelengths.

Optical network-on-chip (NoC) is a new designing of Multi-Processor System-on-Chip (MPSoC). Global bus is the simplest logical topology of optical NoC. Static routing and wavelength assignment is one important communication mechanism of optical NoC. This paper addresses the routing and wavelength assignment (RWA) problem for locally twisted cube communication pattern on global bus optical NoC. For that purpose, a routing scheme, that is an embedding scheme, is proposed, and a wavelength assignment scheme under the embedding scheme is designed. The number of required wavelengths is shown to attain the minimum, guaranteeing the optimality of the proposed scheme.