Metropolitan Area Network architecture design for Optical Flow switching

Abstract

Optical Flow switching (OFS) is a key enabler of future scalable all-optical networks for the large traffic flows. In this thesis, we provide design concepts of efficient physical topology and routing architectures for an all-optical Metropolitan Area Network (MAN) that supports OFS. We use all-to-one stochastic flows to model inter-MAN traffic demands and adopt Moore Graphs and Generalized Moore Graphs as the physical topology. We found good MAN architectures are coupled intimately with media access control protocol designs and must be optimized jointly. Two routing architectures that represent extreme cases were proposed and examined: Quasi-Static Architecture (QSA) and Dynamic Per Flow Routing Architecture (DPFRA). The performance and costs are compared to provide an economical architecture building strategy. We find for the MAN, DPFRA always has the lower queueing delay and lower blocking probability than that of QSA at the expense of more complexity in scheduling, switching, and network management and control. Our analysis based on Moore Graphs and Generalized Moore Graphs indicates that QSA becomes cheaper when the product of the average offered load per node and the normalized delay are equal to or larger than ~ 2 units of wavelengths, with both architectures essentially meeting the same delay or blocking probability requirements. Also, the cost boundary shows that DPFRA with shortest-queue node first routing strategy (sq-first strategy) is preferred only when the delay requirement is stringent and the offered load is low, while QSA is much more suitable for the all-optical MAN to accommodate modest to heavy network traffic. Since OFS is only going to be used in heavy load situations brought on by elephants in the traffic, QSA is the preferred architecture. We have shown the hybrid architecture of QSA and DPFRA is impractical and thus it should be avoided.