Loss, complexity and cost analysis of an optical switching fabric using fixed converters

This paper presents a new wavelength converter sharing scheme for buffer-less switching fabrics, named Shared-Per-Wavelength-Pair (SPWP). In SPWP fixed wavelength converters are organized into different pools, each characterized by a fixed input and output wavelength pair. Packet contention is solved by assigning incoming packets to wavelength converter pools with proper wavelength pair. The SPWP scheme is evaluated and compared to the well-known Shared-Per-Node scheme, which employs tunable wavelength converters. A simple cost model which includes also time analysis in relation to the maturity stage of the optical components has been applied. Packet loss, complexity, and overall cost have been evaluated highlighting how the SPWP can be less expensive than or comparable to SPN in many configurations, while providing the same performance.