No abstract

No abstract

A new control algorithm for multi-plane banyantype switching fabrics has been proposed recently. It has been shown that using this algorithm such switching fabrics can be wide-sense nonblocking (WSNB) when the number of planes is lower than for the strictly nonblocking (SNB) one, and for even number of stages the WSNB switching fabric requires the same number of planes as rearrangeable one. The considered algorithm and WSNB conditions did not take into account crosstalk constraint, which is an important factor in photonic switching. This paper enhanced this algorithm to the case when the first order crosstalk in the switching fabric is not allowed. WSNB conditions for this enhanced algorithm are also derived. It is shown that the number of planes required is less than those derived earlier in other papers for WSNB multiplane banyantype switching fabrics under crosstalk constraint.

No abstract

In this paper, we investigate the three-stage, wavelength–space–wavelength switching fabric architecture for nodes in elastic optical networks. In general, this switching fabric has r input and output switches with wavelength-converting capabilities and one center-stage space switch that does not change the spectrum used by a connection. This architecture is most commonly denoted by the WSW1 (r, n, k) switching network. We focus on this switching fabric serving simultaneous connection routing. Such routing takes place mostly in synchronous packet networks, where packets for switching arrive at the inputs of a switching network at the same time. Until now, only switching fabrics with up to three inputs and outputs have been extensively investigated. Routing in switching fabrics of greater capacity is estimated based on routing in switches with two or three inputs and outputs. We now improve the results for the switching fabrics with four inputs and outputs and use these results to estimate routing in the switching fabric with an arbitrary number of inputs and outputs. We propose six routing algorithms based on matrix decomposition for simultaneous connection routing. For the proposed routing algorithms, we derive criteria under which they always succeed. The proposed routing algorithms allow the construction of nonblocking switching fabrics with a lower number of wavelength converters and the reduction of the overall switching fabric cost.