Abstract
Nonblocking networks has been widely used in telephone networks, various circuit switching systems, and parallel computers. Nowadays, the increasing demand on networks has raised a variety of requirements for the performance of networks, such as bandwidth, low delay, and energy-efficiency, etc. Nonblocking networks can be used to address these challenges. In this thesis, we develop the theory for constructing nonblocking networks with a distributed topology. Applications of such design include wavelength-selective switch (WSS)-based optical ring networks and buffer-less on-chip networks. We also use the new theory to study capacity extension with hybrid software-defined networking for backbone networks.