Differentiated dependability of the 3LIHON concept with main focus on internal node architecture

Abstract

Hybrid optical networks are considered as the most promising architectures for future optical networks, in order to achieve both better cost and performance. Dependability is a topic of increasing interest in order to provide the Quality of Service (QoS) expected for future optical networks. Recently, the 3-Level Integrated Hybrid Optical Network (3-LIHON) has been proposed as a new concept for future optical core networks, including different transport technologies to support a wide range of services. Due to the wide range of future telecommunication services foreseen for next generation optical backbone networks, the 3-LIHON architecture must be provided with differentiated dependability, in order to offer the availability demanded by the most critical services, as well as to utilize network resources efficiently. By focusing in a single 3-LIHON node, this thesis employs component redundancy to present a differentiated survivability model suitable for the 3-LIHON architecture. Several protection mechanisms for two of the three types of traffic supported by 3-LIHON are proposed in this research work. These mechanisms are analyzed by means of different dependability models, i.e. reliability block diagrams and Markov models; and a numerical evaluation of its unavailability is presented. In addition, simulation results measuring the impact on performance of some mechanisms are also presented. Then, the protection mechanisms are compared and evaluated, taking into account not only its unavailability and performance, but also other considerations such as cost and complexity. Finally, based on this evaluation, the best suited mechanisms are selected.