| p-Cycles are a recent innovation in optical network protection. p-Cycles use pre-connected cycles of spare capacity to restore affected working traffic. In this thesis, we present four main advances to the state of the art in p-cycle networking. In our first project we look at the problem of migrating from an existing ring-based transport network to p-cycles. We show, with real-world network cases, how a carrier can migrate to p-cycles without affecting current customers, and gain significant increases in network carrying capacity at little or no additional capital cost. In the second study, we propose methods to incorporate precise path length restrictions in p-cycle design. The issue was that previously such limits could only be implemented in mesh network design. With these tools we were able to demonstrate the existence of a threshold hop limit phenomenon in p-cycle network design. A useful but somewhat counter intuitive result in this second study is that, in p-cycles, limiting the cycle size is an effective surrogate for the more complex technique of precise path length limitation in design. In our third study we propose new methods and strategies to support multiple qualities of service classes in a static p-cycle based network design, using the same global set of resources as required to operate a network with only a single failure protected service class. In this study we show how a p-cycle network operator can support discriminated service classes; such as a pre-emptible class and dual failure protected class, without the need for real-time reconfiguration in the network. Our final and most significant contribution is the design and development of Failure Independent Path Protecting p-Cycles. Failure Independent Path Protecting p-cycles are an advantageous alternative for the survivability mechanism used in current path protected optical networks. At no additional cost, they provide features such as failure independence and full pre-cross-connection. |
