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With the widespread use of real-time applications (VoIP, IPTV, Video conference, etc.) in Internet, protection and resource optimization become increasingly desired. Network protection aims to decrease the interruption time of communications by precomputing backup paths capable to receive and route traffics of affected primary paths upon failures. Resource optimization is achieved by improving data routing and resource sharing: data routing is often optimized by following the shortest paths whereas resource sharing is applied between the backup paths protecting against different failure risks. Two strategies of resource sharing are defined in literature: (1) backup sharing which limits the resource sharing to the backup paths and (2) global sharing which extends the resource sharing to the primary and backup paths. In this paper, we compared the effects of resource sharing strategies on the resource utilization when the primary paths correspond to the shortest ones according to a static metric. With the single failure assumption, we show formally that the resource sharing between primary and backup paths is limited to some few links which cannot form a backup path. Thus, independently of the amount of resources (for instance: bandwidth) that can be shared between the primary and backup paths, the maximum number of backup paths is bounded. In our simulation, we comfort our formal result by showing that the two strategies have close acceptance rates of backup paths and protection bandwidth utilizations. [ABSTRACT FROM AUTHOR]

A multiobjective routing model for multiprotocol label switching networks with multiple service types and path protection is presented in this article. The routing problem is formulated as a biobjective integer program, where the considered objectives are formulated according to a network-wide optimization approach,i.e.the objective functions of the route optimization problem depend explicitly on all traffic flows in the network. A disjoint path pair is considered for each traffic trunk, which guarantees protection to the associated connection. A link-path formulation is proposed for the problem, in which a set of possible pairs of paths is devised in advance for each traffic trunk. An exact method (based on the classical constraint method for solving multiobjective problems) is developed for solving the formulated problem. An extensive experimental study, with results on network performance measures in various randomly generated networks, is also presented and discussed. [ABSTRACT FROM AUTHOR]

The general Multiprotocol Label Switch (MPLS) topology optimisation problem is complex and concerns the optimum selection of links, the assignment of capacities to these links and the routing requirements on these links. Ideally, all these are jointly optimised, leading to a minimum cost network which continually meets given objectives on network delay and throughput. In practice, these problems are often dealt with separately and a solution iterated. In this paper, we propose an algorithm that computes the shortest routes, assigns optimal flows to these routes and simultaneously determines optimal link capacities. We take into account the dynamic adaptation of optimal link capacities by considering the same Quality of Service (QoS) measure used in the flow assignment problem in combination with a blocking model for describing call admission controls (CAC) in multiservice broadband telecommunication networks. The main goal is to achieve statistical multiplexing advantages with multiple traffic and QoS classes of connections that share a common trunk present. We offer a mathematical programming model of the problem and proficient solutions which are founded on a Lagrangean relaxation of the problem. Experimental findings on 2-class and 6-class models are reported. [ABSTRACT FROM AUTHOR]

The suboptimal distribution of the traffic load over the high-speed optical network channels results in poor overall channel utilization and leads to the increased energy consumption. This means that configuration of the network management system including traffic engineering protocols and traffic management mechanisms may have indirect but significant impact on the overall energy efficiency of the particular optical transport network setup. Therefore, we aim in this paper to estimate how energy efficiency of the optical transport network depends on the configuration of the management protocols and mechanisms deployed into the GMPLS and OBS technologies. In addition, we analyze particular configurations of specific mechanisms those allow to increase energy efficiency of the optical transport network without compromising the parameters of the quality of service (QoS). [ABSTRACT FROM AUTHOR]

Segment Routing (SR) combines the simplicity of Link-State routing protocols with the flexibility of Multiprotocol Label Switching (MPLS). By decomposing forwarding paths into segments, identified by labels, SR improves Traffic Engineering (TE) and enables new solutions for the optimization of network resources utilization. This work proposes an Evolutionary Computation approach that enables Path Computation Element (PCE) or Software-defined Network (SDN) controllers to optimize label switching paths for congestion avoidance while using at the most three labels to configure each label switching path. [ABSTRACT FROM AUTHOR]

The evolution of software defined networking (SDN) has played a significant role in the development of next-generation networks (NGN). SDN as a programmable network having 'service provisioning on the fly' has induced a keen interest both in academic world and industry. In this article, a comprehensive survey is presented on SDN advancement over conventional network. The paper covers historical evolution in relation to SDN, functional architecture of the SDN and its related technologies, and OpenFlow standards/protocols, including the basic concept of interfacing of OpenFlow with network elements (NEs) such as optical switches. In addition a selective architecture survey has been conducted. Our proposed architecture on software defined heterogeneous network, points towards new technology enabling the opening of new vistas in the domain of network technology, which will facilitate in handling of huge internet traffic and helps infrastructure and service providers to customize their resources dynamically. Besides, current research projects and various activities as being carried out to standardize SDN as NGN by different standard development organizations (SODs) have been duly elaborated to judge how this technology moves towards standardization. [ABSTRACT FROM AUTHOR]

With a penchant of computing everywhere, everything is going to be connected to the Internet and its data will be used for various progressive purposes. All such required things are connected over the internet and communication is established between them. All the things which are connected may generate data, sometimes data may be used immediately and in some cases data has to be processed and stored for future use. So here comes the use of cloud, the data can be stored in cloud and can be used whenever required. The integration of cloud computing and Internet of Things (IoT) can enable the resource sharing more efficiently than before. From many surveys it is found that integration of IoT and cloud computing is in its initial phase and it has not extended to all application domains due to its inadequate security architecture. So, the paper discusses a secured architecture and the issues involved. The cloud services are integrated through a novel IP/MPLS (Internet Protocol/ Multiprotocol Label Switching) core. Elliptic Curve Cryptography (ECC) is used to ensure complete protection against the security risks. However, new challenges arise when cloud is integrated with IoT. The paper proposes an idea to integrate Internet of Things and Cloud Computing in order to increase the efficiency of computing environment and meet the challenges of speed and accuracy of the services extended by the providers. [ABSTRACT FROM AUTHOR]

In order to provide efficient and flexible resource management and path set-up in high-speed MPLS/GMPLS networks, the PCE (Path Computation Element) architecture was proposed by IETF. Implementation of a central module for the path set-up enables network operators to run path establishment operations for applications with explicitly defined objective functions and QoS requirements. The paper reports on recent research and experimental investigations with PCE-based path computation performed according to the 3-layered traffic engineering (TE) system consisting of: (1) a PCE module equipped with the IBM Cplex LP solver used in the highest layer 3, and (2) a SDN controller in the intermediate layer 2 responsible for transferring path setup requests towards virtual routers in the lowest layer 1. The presented results show usefulness of the PCE-supporting architecture with an SDN controller and applicability of bandwidth-oriented optimization based on real-time focused constraints (path delay limits). We emphasise that even a simple optimization approach shows the power provided by the SDN, i.e., flexibility of flows. This property is in practice not feasible in classical IP or MPLS networks, that is the usage of flow-based routing provided by network programmability really opens opportunities in network tuning. [ABSTRACT FROM AUTHOR]

SUMMARY When dealing with node or link failures in software-defined networking (SDN), the network capability to establish an alternative path depends on controller reachability and on the round-trip times between controller and involved switches. Moreover, current SDN data plane abstractions for failure detection, such as OpenFlow 'Fast-failover,' do not allow programmers to tweak switches' detection mechanism, thus leaving SDN operators relying on proprietary management interfaces (when available) to achieve guaranteed detection and recovery delays. We propose SPIDER, an OpenFlow-like pipeline design that provides (i) a detection mechanism based on switches' periodic link probing and (ii) fast reroute of traffic flows even in the case of distant failures, regardless of controller availability. SPIDER is based on stateful data plane abstractions such as OpenState or P4, and it offers guaranteed short (few milliseconds or less) failure detection and recovery delays, with a configurable trade-off between overhead and failover responsiveness. We present here the SPIDER pipeline design, behavioral model, and analysis on flow tables' memory impact. We also implemented and experimentally validated SPIDER using OpenState (an OpenFlow 1.3 extension for stateful packet processing) and P4, showing numerical results on its performance in terms of recovery latency and packet loss. [ABSTRACT FROM AUTHOR]

Bidirectional multicast mechanisms are used to support multi-point to multi-point (MP2MP) traffic such as video-conferencing. These mechanisms are deployed today in multi-protocol label switching (MPLS) networks using the connectionless mode in which traffic engineering (TE) features such as bandwidth reservation and fast reroute in case of link and/or node failure are not defined. Indeed, TE procedures are defined in MPLS for unicast and multicast point-to-multipoint (P2MP) traffic only. Hence, MP2MP traffic that requires TE procedures is carried out using a full mesh of P2P or P2MP paths. Similarly, a full mesh of P2P and P2MP backup paths should be predefined in order to fast reroute traffic in case of a node failure. This leads to a major scalability problem since MPLS TE paths incur heavy overhead burden on MPLS nodes (CPU and memory). In this paper, we emphasize on fast reroute procedures using MP2MP TE paths. In particular, we define the control plane procedures that should be established. In addition, we present a simulation study that demonstrates the scalability amelioration when using MP2MP TE paths for fast rerouting instead of full mesh P2P and/or P2MP paths. [ABSTRACT FROM AUTHOR]

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The ease of administration and its reduced costs make the MPLS (Multiprotocol Label Switching) technology attractive to those who want to deploy a performant, reliable and scalable private network. Connecting enterprises to remote locations, customers, and vendors via the MPLS is a very flexible solution that is being taken into account by many communication providers. VPN (Virtual Private Networks) is one of the most demanding services for the MPLS technology. The service providing of MPLS Differentiated Services (MPLS DiffServ) allows the customization of each client's traffic. This paper briefly outlines the theoretical aspects of the MPLS technology. The theoretical analysis is summed up in a case study called MPLS_DiffServ, developed with the OPNET Modeler simulator. This simulator allowed us to create a network model and configure the network equipment to provide MPLS DiffServ services. The results that are obtained from the simulation run are suggestive for networking education and a good starting point for the networking research area, as services for new business environment. [ABSTRACT FROM AUTHOR]

Background: Hierarchical Multi-Label Classification is a classification task where the classes to be predicted are hierarchically organized. Each instance can be assigned to classes belonging to more than one path in the hierarchy. This scenario is typically found in protein function prediction, considering that each protein may perform many functions, which can be further specialized into sub-functions. We present a new hierarchical multi-label classification method based on multiple neural networks for the task of protein function prediction. A set of neural networks are incrementally training, each being responsible for the prediction of the classes belonging to a given level. Results: The method proposed here is an extension of our previous work. Here we use the neural network output of a level to complement the feature vectors used as input to train the neural network in the next level. We experimentally compare this novel method with several other reduction strategies, showing that it obtains the best predictive performance. Empirical results also show that the proposed method achieves better or comparable predictive performance when compared with state-of-the-art methods for hierarchical multi-label classification in the context of protein function prediction. Conclusions: The experiments showed that using the output in one level as input to the next level contributed to better classification results. We believe the method was able to learn the relationships between the protein functions during training, and this information was useful for classification. We also identified in which functional classes our method performed better. [ABSTRACT FROM AUTHOR]

Bandwidth Allocation Models (BAMs) are resource allocation methods used for networks in general. BAMs are currently applied for handling resources such as bandwidth allocation in MPLS DS-TE networks (LSP setup). In general, BAMs define resource restrictions by 'class' and allocate the available resources on demand. This is frequently necessary to manage large and complex systems like routing networks. G-BAM is a new generalized BAM that, by configuration, incorporates the 'behavior' of existing BAMs (MAM, RDM, G-RDM and AllocTC-Sharing). In effect, any current available BAM 'behavior' is reproduced by G-BAM by simply adjusting its configuration parameters. This paper focuses on investigating the applicability of using autonomy together with BAMs for improve performance and facilitating the management of MPLS DS-TE networks. It is investigated the applicability of 'BAM switching' using a framework with autonomic characteristics. In brief, it is investigated the switching among 'BAM behaviors' and BAM's reconfiguration with distinct network traffic scenarios by using G-BAM. Simulation results suggest that the autonomic switching of 'BAM behaviors' based on high-level management rules (Service Level Agreements, Quality of Service (QoS) or other police) may result in improving overall network management and operational parameters such as link utilization and preemption. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The convergent communication network will play an important role as a single platform to unify heterogeneous networks and integrate emerging technologies and existing legacy networks. Although there have been proposed many feasible solutions, they could not become convergent frameworks since they mainly focused on converting functions between various protocols and interfaces in edge networks, and handling functions for multiple services in core networks, e.g., the Multi-protocol Label Switching (MPLS) technique. Software-defined networking (SDN), on the other hand, is expected to be the ideal future for the convergent network since it can provide a controllable, dynamic, and cost-effective network. However, SDN has an original structural vulnerability behind a lot of advantages, which is the centralized control plane. As the brains of the network, a controller manages the whole network, which is attractive to attackers. In this context, we proposes a novel solution called adaptive suspicious prevention (ASP) mechanism to protect the controller from the Denial of Service (DoS) attacks that could incapacitate an SDN. The ASP is integrated with OpenFlow protocol to detect and prevent DoS attacks effectively. Our comprehensive experimental results show that the ASP enhances the resilience of an SDN network against DoS attacks by up to 38%. [ABSTRACT FROM AUTHOR]

Network-wide local unambiguous failure localization (NL-UFL) has been demonstrated as an interesting scenario of monitoring trails (m-trails). It attempts to enable every node to autonomously localize any failure event in the network in a distributed and all-optical manner by inspecting a set of m-trails traversing through the node. This paper investigates the m-trail allocation problem under the NL-UFL scenario by taking each link and node failure event into consideration. Bound analysis is performed using combinatorial group testing (CGT) theory and this is followed by the introduction of a novel heuristic on general topologies. Extensive simulation is conducted to examine the proposed heuristic in terms of the required cover length and the number of m-trails to achieve NL-UFL. [ABSTRACT FROM AUTHOR]

To date, NTT has been providing high-quality dedicated services such as analog and high-speed digital services on its time division multiplexing network. NTT has also been shifting its relay networks to packet transport networks in conjunction with the shift to the Next Generation Network. This article introduces a new packet transport multiplexing adapter for dedicated service provisioning on packet transport networks using circuit emulation technologies. [ABSTRACT FROM AUTHOR]

This paper addresses the issue of signalling transport in control plane of the Generalized Multi-Protocol Label Switching (GMPLS) network. The two basic methods for establishing control channels in optical networks are the infibre- out-of-band and the out-of-fibre. Starting from the analysis of benefits and drawbacks of those methods, we propose and investigate a novel, flexible method for signalling transport, which is based on the analysis of the given network topology and combines the basic methods to achieve a trade-off between requirements for low latency and high reliability. Performance analysis has shown that, with hybrid method, data path setup times are close to the ones achieved with the in-fibreout- of-band method, while preserving satisfying reliability and flexibility to integrate into multi-domain networks. [ABSTRACT FROM AUTHOR]

Flow thinning (FT) is a concept of a traffic routing and protection strategy applicable to communication networks with variable capacity of links. In such networks, the links do not attain their nominal (maximum) capacity simultaneously, so in a typical network state only some links are fully available whereas on each of the remaining links only a fraction of its maximum capacity is usable. Every end-to-end traffic demand is assigned a set of logical tunnels whose total capacity is dedicated to carry the demand's traffic. The nominal (i.e., maximum) capacity of the tunnels, supported by the nominal (maximum) link capacity, is subject to state-dependent thinning to account for variable capacity of the links fluctuating below the maximum. Accordingly, the capacity available on the tunnels is also fluctuating below their nominal levels and hence the instantaneous traffic sent between the demand's end nodes must accommodate to the current total capacity available on its dedicated tunnels. The related multi-commodity flow optimization problem is NP-hard and its noncompact linear programming formulation requires path generation. For that, we formulate an integer programming pricing problem, at the same time showing the cases when the pricing is polynomial. We also consider an important variant of FT, affine thinning, that may lead to practical FT implementations. We present a numerical study illustrating traffic efficiency of FT and computational efficiency of its optimization models. Our considerations are relevant, among others, for wireless mesh networks utilizing multiprotocol label switching tunnels. [ABSTRACT FROM AUTHOR]

Compliance with the Service Level Agreement (SLA) metric is a major challenge in a Multiprotocol Label Switching Virtual Private Network (MPLS VPN) because mandatory models must be maintained on both sides of the MPLS VPN in order to achieve end-to-end service levels. The end-toend service of an MPLS VPN can be degraded owing to various issues such as distributed denial of service (DDoS), and Random Early Detection (RED) that prevents congestion and differentiates between legitimate and illegitimate user traffic. In this study, we propose a centralized solution that uses a SLA Violation Detector (SLAVD) and intrusion detection to prevent SLA violation. [ABSTRACT FROM AUTHOR]

Looking in to the modern technology, we see new inventions and innovations which are unique. As an example, during the past years, new technologies have been created in computer networks like metropolitan area network (MAN) that has had a noticeable advance in urban communication. Therefore the aim of this article is to provide and compile information regarding MAN technology and MPLS. Utilizing Ethernet in urban networks needs a developing potential and strength that only exists in MPLS and IP levels. Two layer and three joint networks are the solutions that join simplicity and economy of Ethernet at IP/MPLS scale. Different transfer technologies have been used in MAN so metropolitan services should be given on a mixture of optic and data switches, MPLS have been developed for this work and using generalized-MPLS makes MPLS deployments possible even on none-IP-aware switches. At first, theories about using MAN technology to produce urban networks are explained. Then a set of problems regarding the management of resources and provisioning barriers are introduced following the solutions by means of IP/MPLS network which have been implemented and validated in eSNP simulator. [ABSTRACT FROM AUTHOR]

Up to not so long ago, loop-free alternates (LFA) was the only viable option for providing fast protection in pure IP and MultiProtocol Label Switching-Label Distribution Protocol networks. Unfortunately, LFA cannot provide protection for all possible failure cases in general. Recently, the Internet Engineering Task Force has initiated the remote loop-free alternates (rLFA) technique as a simple extension to LFA, to boost the fraction of failure cases covered by fast protection. Before further standardization and deployment, however, it is crucial to determine to what extent rLFA can improve the level of protection against single link or node failures in a general IP network, as well as to find optimization methods to tweak a network for 100 % rLFA coverage. In this paper, we take the first steps towards this goal by solving these problems in the special, but practically relevant, case when each network link is of unit cost. We also provide preliminary numerical evaluations conducted on real IP network topologies, which suggest that rLFA significantly improves the level of protection, and most networks need only 2-3 new links to be added to attain 100 % failure case coverage irrespectively of whether link or node protection is considered. [ABSTRACT FROM AUTHOR]

This article presents analysis and possible reactions of MPLS network on unauthorized access and on device's failure. Five Cisco routers joined into a core network were used to conduct the project. The devices were connected into a classic reliability model with envelope shape. The key aspects of the research were incidents' simulation in line with previously prepared scenarios as well as diagnosis of network's reactions to a particular type of a device failure. These effects were modelled using special devices such as analysers and generators of data traffic. Additionally, the range of the project included measuring convergence time of the routing protocols acting inside the network combined with analysis of reactions to forced changes of route. [ABSTRACT FROM AUTHOR]

Multi Protocol Label Switching (MPLS) has been used to provide traffic engineering and high speed networking. MPLS is an evolving network technology. MPLS is a framework which is introduced by IETF. It is a differentiated and scalable framework. MPLS delivers end-to-end IP services with the use of simple configuration and management. Fault tolerance is an important Quality Of Service factor. Fault tolerance needs to be considered to maintain network survivability. Fault tolerance is very important in every network system because it provides the facility to operate the network if any one or more parts of the system are damaged. The network devices are enabled by MPLS to specify path based on quality of service and bandwidth. The main use of MPLS technology is to speed up the network flow with the use of labels. [ABSTRACT FROM AUTHOR]

A resilience analysis of protection cycles ( p-cycle) configurations for Double Rings with Dual Attachment (DRDAs) architectures is presented in this work. DRDAs are composed of two rings with corresponding nodes connected by two separated links. There are several possible configurations of p-cycles, which may be used in DRDAs for improving link or node protection upon link failure. The values of the parameters Mean Time To Failure and Mean Time To Disconnection are analysed in the paper to show the best choice of p-cycles in DRDAs architectures. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

MPLS is enhanced technology to improve the Quality of service parameters. In the paper the study of Quality of Service performance is done over NON-MPLS based and MPLS-based Network on the UDP and TCP data packet type. Also the study has been done by varying the packet size of the UDP and TCP data showing the comparison of the performances. Various parameters of the quality of services as throughput, packet delivery ratio, and total packet loss are taken and analysis has been done with the x-graph and NS2 on the same network using NON- MPLS and MPLS-based network. The main focus of the paper is improved analysis on the QoS with the advanced technologies in which the MPLS and supporting traffic engineering is one of them. The protocol used to implement the newly proposed MPLS technology are LDP and CR-LDP providing comparative study with the conventional NON-MPLS based network that uses default protocol OSPF. [ABSTRACT FROM AUTHOR]

The emergence of new kinds of applications and technologies (e.g., data-intensive applications, server virtualization, and big data technology) has led to a higher utilization of network resources. These services imply increased bandwidth consumption and unexpected congestions, especially in backbones. In this article, a novel proposal is studied with the aim of improving the performance of prioritized forwarding equivalence classes in congested Multiprotocol Label Switching Transport Profile (MPLS-TP) domains. The congestion impact on those QoS-aware services that require high reliability and low delay is analyzed. A new policy has been implemented on MPLS-TP, which is a technology that provides QoS by means of flow differentiation in the Internet backbones. The proposal is known as Gossip-based local recovery policy and is offered as an operation, administration, and management function to allow local recovery of lost traffic for MPLS-TP privileged forwarding equivalence classes. In order to fulfill the requirements for implementation on MPLS-TP, a minimum set of extensions to resource reservation protocol traffic engineering has also been proposed to provide self-management capable routes. Finally, we have carried out a performance improvement measurement by means of an analytical model and simulations. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In many modern networks, such as datacenters, optical networks, and multiprotocol label switching (MPLS), the delivery of a traffic flow with a certain bandwidth demand over a single network path is either not possible or not cost-effective. In these cases, it is very often possible to improve the network's bandwidth utilization by splitting the traffic flow over multiple efficient paths. While using multiple paths for the same traffic flow increases the efficiency of the network, it consumes expensive forwarding resources from the network nodes, such as TCAM entries of Ethernet/MPLS switches and wavelengths/lightpaths of optical switches. In this paper, we define several problems related to splitting a traffic flow over multiple paths while minimizing the consumption of forwarding resources, and present efficient algorithms for solving these problems. [ABSTRACT FROM PUBLISHER]

Multi-Protocol Label Switching (MPLS) being one such technology for increasing the efficiency. This technology of forwarding data packets (of a fixed size labels) is based upon a pre-determined path that the data packet needs to traverse, where then coming packet labels are examined to determine the next hop (or the next part of the journey), the old label is then replaced with a new one (label) and once again it is forwarded to the next hop, and the journey continues till it reaches its destination. This dissertation discusses a local and global recovery scheme when the link failure occurs within the backup path as well in the original path. In the existing technique, if any fault occurs at any LSR then detour LSR will compute the protected LSP. This protected LSP will be used as the backup path to transfer the data. But the global path may be more optimized as compared to this protected path. The proposed techniques hybridize the local repair as well as the global recovery schemes to find the optimized recovery path. Whenever any fault occurs at any LSR then the Detour LSR give provides the protected path (local repair) and the global recovery will provide different path (Haskin's model). The total path cost of each is compared and the optimized path is selected in the proposed model. Moreover the original path is recovered after repairing the faulty LSR. [ABSTRACT FROM AUTHOR]