Dynamic wavelength routing in all-optical mesh networks

Wavelength-division multiplexing (WDM) offers the capability to handle the increasing demand of network traffic in a manner that takes advantage of already deployed optical fibers. Lightpaths are optical connections carried end-to-end over a wavelength on each intermediate link. Wavelengths, are the main resource in WDM networks. Due to the inherent channel constraints, a dynamic control mechanism is required to efficiently utilize the resource to maximize lightpath connections. In this paper, we investigate a class of adaptive routing called Dynamic Wavelength Routing (DWR), in which wavelength converters (WCs) are not utilized in the network. The objective is to maximize the wavelength utilization and reduces the blocking probability in an arbitrary network. This approach contains two sub-algorithms: Least Congestion with Least Nodal-degree Routing algorithm (LCLNR) and Dynamic Two-end Wavelength Routing algorithm (DTWR). We demonstrate that DWR can significantly improve the blocking performance, and the results achieved as good as placing sparse WCs in the network.