André C. Drummond

PCE-based inter-domain lightpath provisioning

Despite the research advances in intra-domain light-path provisioning in WDM networks, efficient and practical schemes for path computation and resource advertisement in multi-domain mesh networks still need to be developed. Most of the proposed solutions in the literature lacks the ability to convey optical network-specific Traffic Engineering information and are based on periodic message flooding technique. The proposed solution provides a novel and economical way to disseminate information while performing the domain chain computation. It also provides a policy-based wavelength selection scheme that allows a load balanced provisioning of end-to-end lightpaths.

New Distance-Adaptive Modulation Scheme for Elastic Optical Networks

Elastic optical networks enter as a promising technology for the future of high-capacity networks. Its features provide flexibility and superior scalability in spectrum allocation following the growing demands of Internet traffic. In this letter, we propose a novel approach to address the routing, modulation level, and spectrum allocation (RMLSA) problem through the use of a distance-adaptive modulation scheme that enables the routing of traffic through multiple hops in virtual topology, enabling smoothing out the spectrum continuity and transmission distance constraints. The results showed that the use of the proposed scheme provide a gain of up to 82% in the bandwidth blocking rate using 7% less spectral resources in the network compared with the literature. This proposal opens a new avenue for future research, allowing new solutions for RMLSA problem.

Leveraging adaptive modulation with multi-hop routing in elastic optical networks

The technology used for data transmission in optical networks is going through significant changes in response to the rapid growth of Internet traffic and emerging high performance applications, boosting research on how to satisfy the increasing demands with the available resources. In this scenario, the elastic optical networks paradigm enables improved provisioning through flexibility and scalability in spectrum assignment. This work proposes data and optical grooming and the use of spectral modulation control as a solution to the Routing, Modulation Level, and Spectrum Allocation problem in a dynamic traffic context. The proposed algorithm obtains the greatest spectrum aggregation possible using higher modulation levels through multiple hops in the virtual topology. Experiments show that this approach results in reduced blocking without impacting the use of the networks resources.

Leveraging multipath routing and traffic grooming for an efficient load balancing in optical networks

Optical networks can benefit from multipath routing by routing traffic over diverse fiber links to fulfill bandwidth requirements, balance network load and improve resource utilization. This paper focuses on the effectiveness of multipath routing on aggregating residual bandwidth of the established lightpaths using dynamic traffic grooming. An optimization model based on Integer Linear Programing (ILP) is formulated to leverage multipath routing and grooming to serve connection requests with known duration, in a scenario where the dynamic traffic can demand bandwidth either larger or smaller than a single wavelength capacity. The impact of a balancing policy, referred to as Holding Time Balancing (HTBalancing), on multipath routing with traffic grooming in optical networks is also investigated. Numerical results show that the proposed optimization model can achieve a lower bandwidth blocking and a better load balancing with HTBalancing policy, when compared with single path routing. The proposed relaxation algorithm can effectively find near optimal solutions, and be applied in realistic scenarios.

Multipath routing with topology aggregation for scalable inter-domain service provisioning in optical networks

Abstract In this paper, we propose to use static virtual topology for a scalable inter-domain optical service provisioning, while addressing the resource efficiency issue by using multipath routing. To this end, we discuss methods for virtual topology aggregation with consideration of inter-domain routing, and propose two heuristic algorithms for two representative applications, referred to as real-time streaming and bulk data transfer. We consider specific requirements of each application, including transmission deadline and jitter, and evaluate the impact of differential delay issue of multipath routing on the performance of proposed algorithms. Numerical results show that the proposed multipath routing algorithms yield a low blocking ratio of inter-domain connections even on the static virtual topology, which is known for poor blocking performance otherwise. The resulting differential delay is sufficiently small for the studied applications, and can be compensated with relatively small buffers. We show that a scalable inter-domain service provisioning in optical networks can be achieved by using a combination of static virtual topology and multipath routing.

A comparison of measurement-based equivalent bandwidth estimators

This paper compares the efficacy of two measurement based equivalent bandwidth estimators: the Gaussian approximation allocation and the one based on fractal envelope process. These estimators represent a trade-off between accuracy and computational complexity. The estimators were evaluated under different scenarios using video, voice and data traffic.

Schemes for inter-domain lightpath establishment based on PCE architecture

Abstract Despite the research advances in intra-domain lightpath provisioning in Wavelength Division Multiplexing networks, efficient and practical schemes for path computation and resource advertisement in multi-domain mesh networks still need to be developed. Most of the solutions proposed in the literature lacks the ability to convey optical network-specific Traffic Engineering information and are based on a periodic message flooding technique. This paper proposes three novel solutions for inter-domain lightpath provisioning in WDM circuit switched mesh networks. Two routing advertisement schemes and two path and wavelength selection criteria for the PCE architecture are proposed. The solutions provide a complete inter-domain routing and wavelength solution. Simulation experiments show the effectiveness of the proposed solutions which significantly reduce the total amount of message exchanged as well as overall call blocking.

Holding-time-aware dynamic traffic grooming algorithms based on multipath routing for WDM optical networks

This paper investigates approaches for the traffic grooming problem that consider connection holding-times and bandwidth availability. Moreover, solutions can indicate the splitting of connections into two or more sub-streams by multipath routing and fine-tuned by traffic grooming to utilize network resources better. Algorithms are proposed and the results of simulations using a variety of realistic scenarios indicate that the proposed algorithms significantly reduce the blocking of connection requests yet promote a fair distribution of the network resources in relation to the state-of-the-art solutions.

A Survey of Random Forest Based Methods for Intrusion Detection Systems

Over the past decades, researchers have been proposing different Intrusion Detection approaches to deal with the increasing number and complexity of threats for computer systems. In this context, Random Forest models have been providing a notable performance on their applications in the realm of the behaviour-based Intrusion Detection Systems. Specificities of the Random Forest model are used to provide classification, feature selection, and proximity metrics. This work provides a comprehensive review of the general basic concepts related to Intrusion Detection Systems, including taxonomies, attacks, data collection, modelling, evaluation metrics, and commonly used methods. It also provides a survey of Random Forest based methods applied in this context, considering the particularities involved in these models. Finally, some open questions and challenges are posed combined with possible directions to deal with them, which may guide future works on the area.

High-performance IP lookup using Intel Xeon Phi: a Bloom filters based approach

IP lookup is a core operation in packet forwarding, which is implemented using a Longest Prefix Matching (LPM) algorithm to find the next hop for an input address. This work proposes and evaluates the use of parallel processors to deploy an optimized IP lookup algorithm based on Bloom filters. We target the implementation on the Intel Xeon Phi (Intel Phi) many-core coprocessor and on multi-core CPUs, and also evaluate the cooperative execution using both computing devices with several optimizations. The experimental evaluation shows that we were able to attain high IP lookup throughputs of up to 182.7 Mlps (Million packets per second) for IPv6 packets on a single Intel Phi. This performance indicates that the Intel Phi is a very promising platform for deployment of IP lookup. We also compared the Bloom filters to an efficient approach based on the Multi-Index Hybrid Trie (MIHT) in which the Bloom filters was up to 5.1 × faster. We also propose and evaluate the cooperative use of CPU and Intel Phi in the IP lookup, which resulted in an improvement of about 1.3 × as compared to the execution using only the Intel Phi.