Resilient Resource Allocation Schemes in Optical Networks

Recent studies show that deliberate malicious attacks performed by high-power sig- nals can put large amount of data under risk. We investigate the problem of sur- vivable optical networks resource provisioning scheme against malicious attacks, more specically crosstalk jamming attacks. These types of attacks may cause ser- vice disruption (or possibly service denial). We consider optical networks based on wavelength-division multiplexing (WDM) technology and two types of jamming at- tacks: in-band and out-of-band attacks. We propose an attack-aware routing and wavelength assignments (RWA) scheme to avoid or reduce the damaging effects of potential attacking signals on individual or multiple legitimate lightpaths travers- ing the same optical switches and links. An integer linear programs (ILPs) as well as heuristic approaches were proposed to solve the problem. We consider dynamic traffic where each demand is dened by its start time and a duration. Our results show that the proposed approaches were able to limit the vulnerability of lightpaths to jamming attacks. Recently, large-scale failures caused by natural disasters and/or deliberate at- tacks have left major parts of the networks damaged or disconnected. We also investigate the problem of disaster-aware WDM network resource provisioning in case of disasters. We propose an ILP and efficient heuristic to route the lightpaths in such a way that provides protection against disasters and minimize the network vi resources such as the number of wavelength links used in the network. Our models show that signicant resource savings can be achieved while accommodating users demands. In the last few years, optical networks using Space Division Multiplexing (SDM) has been proposed as a solution to the speed bottleneck anticipated in data center (DC) networks. To our knowledge the new challenges of designing such communica- tion systems have not been addressed yet. We propose an optimal approach to the problem of developing a path-protection scheme to handle communication requests in DC networks using elastic optical networking and space division multiplexing. We have formulated our problem as an ILP. We have also proposed a heuristic that can handle problems of practical size. Our simulations explore important features of our approach

On the offline physical layer impairment aware RWA algorithms in transparent optical networks: state-of-the-art and beyond

In transparent optical networks with no regeneration, the problem of capacity allocation to traffic demands is called "Roting and Wavelength Assignment". Much work on this topic recently has focused on the dynamic case, whereby demands arrive and must be served in real-time. In addition, due to lack of regeneration, physical impairments accumulate as light propagates and QoT may become inappropiate (e.g., too high Bit Error Rate). Considering the physical layer impairments in the network planning phase gives rise to a class of RWA algorithms: offline Physical Layer Impairment Aware- (PLIA-)RWA. This paper makes a survey of such algorithms, proposes a taxonomy, and a comparison between these algorithms for common metrics. We also propose a novel offline PLIA-RWA algorithm, called POLIO-RWA, and show through simulations that it decreases blocking rate compared with other PLIA-RWA algorithms.Postprint (published version

Attack-Aware Routing and Wavelength Assignment of Scheduled Lightpath Demands

In Transparent Optical Networks, tra c is carried over lightpaths, creating a vir- tual topology over the physical connections of optical bers. Due to the increasingly high data rates and the vulnerabilities related to the transparency of optical network, security issues in transparent wavelength division multiplexing (WDM) optical net- works have become of great signi cance to network managers. In this thesis, we intro- duce some basic concepts of transparent optical network, the types and circumstances of physical-layer attacks and analysis of related work at rst. In addition, based on the previous researches, we present a novel approach and several new objective cri- terions for the problem of attack-aware routing and wavelength assignment. Integer Linear Programming (ILP) formulation is used to solve the routing sub-problem with the objective to minimize the disruption of physical-layer attack as well as to opti- mize Routing and Wavelength Assignment (RWA) of scheduled transparent optical network

Security-Aware RWA for Dynamic Traffic Using Path Protection In WDM Networks

Security and attack management have become the prime concern for the network operators due to high data transfer rates and vulnerabilities associated with transparency in WDM networks. In the recent years, there is a substantial increase in perception to develop suitable mechanisms for subduing the adverse effects of malicious attacks such as high power jamming and tapping attacks.In transparent optical networks (TONs) traffic is carried over the optical fibers in the form of signals called lightpaths, creating a virtual topology over the physical interconnections of an optical fiber. This allows an exchange of an enormous amount of data at a very high speed. A fault or an attack on the network can lead to data tampering and data loss. Unlike faults, malicious attacks may not be localized and we cannot handle them with the standard fault-tolerance mechanisms in WDM networks. The Routing and Wavelength Assignment (RWA) problem assigns appropriate routes and wavelengths to all associated lightpaths in the network. Most the researchers considered the static traffic model, where the network requests (i.e. lightpaths to be established) are known in advance and last over long durations. In this thesis, we are solving the security-aware problem for dynamic requests by using protection strategy known as dedicated path protection (DPP). In the dynamic model, lightpaths are generated on-demand, and RWA must be performed based on available resources that are not being used by ongoing lightpaths. We propose an Integer linear programming (ILP) formulation to maximize requests satisfaction and reducing the disruption in the network due to malicious attacks (In-band and out-band)