A Hierarchical Approach for Modelling an MPLS Network Using VHDL

Aggregates of real‐time traffic may experience changes in their statistical characteristics often manifesting non stationary behavior. In multi protocol label switching (MPLS) networks this type of the traffic is assigned constant amount of resources. This may result in ineffective usage of resources when the load is below than expected or inappropriate performance when the load is higher. In this paper we propose new algorithm for dynamic resource adaptation to temporarily changing traffic conditions. Assuming that network nodes may reallocate resources on‐demand using automatic bandwidth adjustment capability of MPLS framework, the proposed algorithm, implemented at ingress MPLS nodes, dynamically decides which amount of resources is currently sufficient to handle arriving traffic with given performance metrics. This decision is then communicated to interior MPLS nodes along the label switched path. As a basic tool of the algorithm we use change‐point statistical test that signals time instants at which statistical characteristics of traffic aggregates change. The major advantage of the proposed approach is that it is fully autonomous, that is, network nodes do not need any support from hosts in terms of resource reservation requests. The proposed algorithm is well suited for traffic patterns experiencing high variability, especially, for non stationary type of the traffic.

In Multiprotocol Label Switching (MPLS) networks, Label Switching Routers (LSRs) cannot only transmit IP packets fast with cut-through mechanism, but also solve traffic engineering issue. In this paper, we will consider the case where real time and non-real time traffic arrive at LSR and analyze their delay and packet loss probability under the assumption that the cut-through transmission is applied only to real time traffic. Furthermore, we discuss the bandwidth allocation policy and the buffer dimensioning to meet the requirement of both real time and non-real time traffic, and show the guide for QoS provisioning in MPLS networks.

This paper presents a study on traffic management for transporting progressive video streams over multiprotocol label switching (MPLS) networks. Based on the variety of MPLS service models, a unique multi-stream video transport scheme is proposed. A 3-D subband video coder is used in generating the source data traffic. A special feature of this video coder is that the coded bit stream can be easily segmented into sub-streams with different quality of service (QoS) requirements. After source coding and segmentation, multiple streams are formed. Upon their entering into the network, they are labeled with different forwarding equivalence classes (FECs). Specific label switch paths (LSPs) are selected by the MPLS protocols to achieve the desired quality levels. The proposed scheme is studied under the metrics such as the end-to-end video delivery quality, the bandwidth consumption and the pricing of the service. Extensive simulations have been conducted in this study, and some of the results are presented in this paper.

Recent advancements in Multi-Protocol Label Switching (MPLS) based technology has brought transformation in next generation computer networking by enhancing Traffic Engineering (TE) features and Quality of Service (QoS) service parameters. Nowadays traffic management is successfully controlled by MPLS technology especially in case of underutilized or over-utilized links. The main dissimilarity between Internet Protocol (IP) and MPLS lies in the complexity of routing or switching look-up tables that seem to be less complex in latter type of networks. MPLS network tunneling is relied on a QoS routing algorithm thereby establishing a bandwidth guaranteed and less delay paths from source to destination. In this paper, a hybrid algorithm named Hybrid MPLS Tunneling Algorithm (HMTA) which comprises of bandwidth and delay differentiation techniques as well as on the basis of priority bits contained in each data packet is proposed which improves QoS routing of MPLS networks. In proposed algorithm, the differentiation of links is based on the threshold values of bandwidth and delay which is also named as the link state information. The link differentiation is done to reduce the blocking probability and number of times QoS state exchangestake place resulting in increment of QoS overheads. In order to improve the performance, this new approach is using high priority bits to accurately transmit the data-labeled or content-labeled packets to its destination by using the simulation tool MATLAB to perform the experiments. Finally, the simulation experiments demonstrate that proposed approach results in less blocking probability, high utilized bandwidth, lower packet loss, high network utilization with minimal delay.

Fast network re-optimization schemes for MPLS and optical networks

An essential solution is available in Multi-protocol label switching (MPLS), which solve the problems faced by present-day networks: speed, scalability, quality-of-service (QoS) management, and traffic engineering. This paper is an extension of work on Fuzzy based Packet Scheduling Algorithm (FPSA) combined with Packets Processing Algorithm (PPA) in an Internet Protocol/Multi-Protocol Label Switching (IP/MPLS) networks. This will make provision for an intelligent service to the Label Switched Path (LSP) in MPLS networks. Several research work have been proposed on the MPLS Traffic Engineering. However, it is still imperative to further research on the effect of bandwidth increment on the core network using different mechanisms such as the analytical model of MPLS, expert-based packet scheduling algorithm for MPLS QoS support. Since MPLS is not able to provide intelligent routing, it is necessary to propose an intelligent expert system of FPSA combined with PPA. And analytical model of packet forwarding in the MPLS network would be given to provide suitable solution to traffic congestion and reliable services. Furthermore, the network model created using Network Simulator (NS 2), which carries non-real time application such as File Transfer Protocol (FTP) with bandwidth variations. The results obtained from trace files are interpreted by AWK script and used for the further analysis.

In multi-protocol label switching (MPLS) networks, traffic demands can be routed along tunnels called label switched paths (LSPs). One tunnel is characterized by a path in the network and a reserved bandwidth. These tunnels can be created and deleted dynamically, depending on traffic demand arrivals or departures. After several operations of this type, the network resources utilization can be unsatisfactory, with for instance congestion or too long routing paths. One way to improve it is to reroute tunnels. Different rerouting procedures may be applied, breaking tunnels or using make-before-break. This has to be adapted to the LSP quality of service (QoS) requirements. Moreover, for network management purposes, we would like to control the number of rerouting operations to perform. A global rerouting framework is proposed, which enables to consider independently each class of LSPs. Then, a mathematical model is introduced. As it appears very hard to solve to optimality, a heuristic based on randomized rounding is proposed. Finally, the designed tool has enabled a numerical study on the proportion of tunnels to reroute in order to reach near-optimal network states.

This paper presents a Constraint-Based Routing (CBR) algorithm for Multiprotocol Label Switching (MPLS) network which is designed for mapping among any layer-2 protocols and any layer-3 protocols of the OSI model. The MPLS network has capability of routing with some specific constraints for supporting desire Quality of Service (QoS). The most important constraint is the demand bandwidth. The efficient routing algorithm should have low percentage of call-setup request blocking, high network utilization and low calculation complexity. There are many previously proposed algorithms such as minimum hop algorithm, widest shortest path algorithm, and minimum interference routing algorithm. In this paper, a new algorithm is proposed. The proposed algorithm is based on the weight calculation of an amounts of paths routed over each links in the network. From the simulation results, the proposed algorithm has well performance over high network utilization, low blocking percentage and low complexity.

In order to provide uninterrupted services whenever a node or link in the network fails, fast recovery techniques are required. Multi Protocol Label Switching (MPLS) is a very popular technique that applies recovery mechanism to such failure. Algorithms and graph theory have been well researched areas of research. Graph theoretic concepts and algorithms play important role in MPLS networks. The aim of this survey is to discuss a different recovery techniques, advantages and disadvantages of various path restoration techniques.

This paper deals with the problem of reroute sequence planning for label switched paths (LSPs) in multiprotocol label switching (MPLS) networks. This problem arises when the path set is recalculated by a global optimization method for achieving a better resource utilization. In this case we have to find a sequence of the one-by-one reconfiguration of the LSPs from their original paths to the optimized paths, with the constraint that the link capacities should not be violated at any time during the reroute process. The problem is computationally hard in real-world situations because of the large amount of routers and LSPs in the network, so that neither exact nor approximation algorithms have practical relevance. We introduce a number of heuristic approaches, which are investigated through extensive empirical tests based on real network topologies. The results reveal the complexity of the problem. We propose possible solutions and suggest future research directions for alternative answers to the reroute sequence planning.

Today the Internet has serious problems of an explosive increase of traffic caused by increased numbers of users. These problems degrade prominently the quality of service (QoS), and make it difficult to provide multimedia and real time services. Various technologies are proposed to solve these problems. Especially, MPLS (multiprotocol label switching) was developed for the Internet backbone network. The faults occurring in high-speed networks such as MPLS may cause massive data loss and degrade QoS. To deliver a reliable service, however, MPLS requires a set of procedures to provide a suitable protection for the traffic carried on the label switched paths (LSPs). This paper proposes an enhanced scheme for fast rerouting to preassigned LSPs in case of LSP or link failures. In order to minimize back-up resources, it allows possibility of splitting traffic of faulty LSP onto available alternative LSPs for fault recovery. We use preassigned LSPs for restoration when fault occurs. Total traffic throughput and resource utilization can be maximized if the traffic of faulty LSP is split over multiple pre-assigned LSPs. In this paper a new approach to providing fault tolerance in MPLS networks using case-based reasoning as a method to find out the amount of traffic forwarded on each pre-assigned LSP based on past experiences if loading process is presented. The pre-assigned LSPs and the percentage of traffic splitting are calculated off-line based on desired QoS and capacity constraints.

Mapping between two heterogeneous networks, Multi Protocol Label Switching (MPLS) and IEEE 802.11e is choice of future technology as it has ability to perform traffic engineering and create the corresponds between LSP (Label Switch Path) and AC (Access Category). This paper discusses the mapping between IEEE 802.11 MPLS integration to achieve quality of service on MPLS networks. MPLS and 802.11e is very useful approach for today’s internet to ensure the Quality of service the end to end. It talks about different approaches to map 802.11e Access Categories (AC) to Label Switched Path (LSP) and their advantages. It then introduces the concept of encapsulated LSPs to achieve future QoS, which requires further study to examine its practicability.

Multiprotocol label switched (MPLS) networks were introduced to enhance the network’s service provisioning and optimize its performance using multiple protocols along with label switched based networking technique. With the addition of traffic engineering entity in MPLS domain, there is a massive increase in the networks resource management capability with better quality of services (QoS) provisioning for end users. Routing protocols play an important role in MPLS networks for network traffic management, which uses exact and approximate algorithms. There are number of artificial intelligence-based optimization algorithms which can be used for the optimization of traffic engineering in MPLS networks. The paper presents an optimization model for MPLS networks and proposed dolphin-echolocation algorithm (DEA) for optimal path computation. For Network with different nodes, both algorithms performance has been investigated to study their convergence towards the production of optimal solutions. Furthermore, the DEA algorithm will be compared with the bat algorithm to examine their performance in MPLS network optimization. Various parameters such as mean, minimum /optimal fitness function values and standard deviation.

In multi-protocol label switching (MPLS) domains, the speed-up by eliminating the IP header lookup and the support of QoS are basic roles of label switch routers (LSRs). Core LSRs inside MPLS network forward packets at the network-specific link layer. However, edge LSRs on the MPLS network boundary would forward packets at the link layer and at the network layer. The support of both high-speed forwarding and the guarantee of QoS at the edge LSRs are very important. This paper proposes the packet forwarding architecture of the ATM-label edge router (ATM-LER), which is an MPLS edge LSR on the public ATM network boundary, to support the high-speed forwarding. The forwarding control procedures and the related works of the ATM-LER are also discussed.

Multi Protocol Label Switching (MPLS) is being used in many corporate networks and public infrastructures and as a backbone technology of many Autonomous Systems. Because of its importance, what is needed is to find out simulators able to simulate MPLS networks whose results reflect the real environment as much as possible. In this article, we will show real measurements from the Railway Infrastructure Administrator (ADIF, the Spanish railway infrastructure manager) MPLS network and we will compare them with the results obtained by the freeware simulator ns2. We will check the level of reliability provided by the simulator and we will know under which parameters its results will be similar with those obtained from the real network. These results could be taken into account later to simulate real-time critical services over MPLS networks.