Survivable mesh-network design & optimization to support multiple QoP service classes

Every second, vast amounts of data are transferred over communication systems around the world, and as a result, the demands on optical infrastructures are extending beyond the traditional, ring-based architecture. The range of content and services available from the Internet is increasing, and network operations are constantly under pressure to expand their optical networks in order to keep pace with the ever increasing demand for higher speed and more reliable links

Protection and restoration algorithms for WDM optical networks

Currently, Wavelength Division Multiplexing (WDM) optical networks play a major role in supporting the outbreak in demand for high bandwidth networks driven by the Internet. It can be a catastrophe to millions of users if a single optical fiber is somehow cut off from the network, and there is no protection in the design of the logical topology for a restorative mechanism. Many protection and restoration algorithms are needed to prevent, reroute, and/or reconfigure the network from damages in such a situation. In the past few years, many works dealing with these issues have been reported. Those algorithms can be implemented in many ways with several different objective functions such as a minimization of protection path lengths, a minimization of restoration times, a maximization of restored bandwidths, etc. This thesis investigates, analyzes and compares the algorithms that are mainly aimed to guarantee or maximize the amount of remaining bandwidth still working over a damaged network. The parameters considered in this thesis are the routing computation and implementation mechanism, routing characteristics, recovering computation timing, network capacity assignment, and implementing layer. Performance analysis in terms of the restoration efficiency, the hop length, the percentage of bandwidth guaranteed, the network capacity utilization, and the blocking probability is conducted and evaluated

Survivable multipath provisioning schemes in mesh transport networks

Back to the 1 960s, Internet originated from the military research of survivable, fault-tolerant and distributed computer networks. Half-century later, quarter of Earth' s population use Internet services. International business transactions are promoted by the accelerated information interaction across the world. With the prosperity Internet brought to our society, its survivability and capacity become an important issue. We investigate the problem of efficient multipath provisioning in backbone mesh networks by employing pool sharing and traffic decentralization techniques such as working and backup traffic split and mix-routing. With Multipath provisioning, a connection request can be split and diversely routed on to several paths. A feature that has two improvements over single-path provisioning: 1 ) load balancing among working paths, and 2) reducing the bandwidth of backup path. However, these diversely routed paths are subject to the limitation of network topology, which limit the number of available paths that can be found inside the network

Integrated mechanisms for QoS and restoration in mesh transport networks

Survivable networks have the capability to survive from the events of network components failures. The resilience mechanisms in these networks protect and restore the impaired communication paths by using spare capacity. On the other hand, Quality of Service (QoS) mechanisms focus on network capabilities that provide the facilities to differentiate network traffic and offer different levels of service to each class of traffic. Traditionally the survivability algorithms were applied at the physical (optical) layer, whereas the QoS mechanisms mainly applied at packet-forwarding level. Recent technological breakthroughs can now facilitate novel forwarding techniques for optical data bursts that make it possible to capture packets at the optical layer. A major challenge in the transfer of these ultrahigh-speed data bursts is to allocate resources according to QoS specifications and to provide spare capacity required to address link failures

Provisioning lightpath demands with quality of protection grades in WDM optical networks

Master'sMASTER OF ENGINEERIN