Routing and wavelength assignment (RWA) algorithms must strike a balance between finding routes with high quality of transmission (QoT) and finding routes that will not interfere with allocating future traffic. Too much emphasis on the first will concentrate traffic along major routes causing congestion whilst too much emphasis on the second will cause individual transceivers to operate below their capabilities increasing both cost and power consumption. This paper presents a low-complexity algorithm that shows that focusing on wavelength packing allows for greater overall traffic whilst giving only slight penalties for latency and required transceivers. Our algorithm comfortably outperforms kSP-FF routing for the same complexity and typically betters congestion aware routing whilst reducing complexity. We show these results on 4 simplified networks based on deployed topologies before replicating them on 2,000 artificially generated topologies based on real node locations in Germany and the USA. Capacity for each topology was found with an integer linear program to which our algorithm compares favorably suggesting it provides a scalable alternative to global optimization.

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Equations are derived which describe the growth of epitaxial islands on a crystalline substrate subject to certain restrictions, and an attempt is made to define the limits of their application in a physical system. For an initial random distribution of point nuclei, the growth of islands which instantaneously coalesce to a fixed shape obeys equations of the form : In ( N / N 0 ) = -2 N ⅓ 0 A V -⅔ T ⅔ for N 0 > N > 10 -2 N 0 and P = P 0 (1- N / N 0 ) for all N , where 0.5 < P 0 < 0.6. In these equations the island distribution is described in terms of three parameters: the island density N , the fractional surface coverage P and the mean thickness T . The constants A and V are fixed by the shape of an island of size r , such that the volume is Vr 3 and the interface area is Ar 2 .

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We propose an adaptive sequential loading algorithm that approaches the ILP throughput. Of 2,000 network realizations tested, shortest path routing achieves >90 % of the maximum throughput in 341 cases c.f. 1,904 with the proposed algorithm.