MPLS Research Articles

Control of Frequency Conversion and Defragmentation for Super-Channels [Invited

Super-channel (or multi-carrier) transmission is today one of the most promising techniques for the support of high line rates, which are required to satisfy the massive increase of Internet traffic. Moreover, flex-grid optical networks seem to be the candidates for backbone networks by enabling high spectral efficiency thanks to the adoption of the ITUT flex-grid. Such networks may suffer from spectrum fragmentation, which can prevent the establishment of new connections. For this reason, defragmentation techniques (i.e., reoptimization) have been widely studied, especially considering single-carrier transmission. Inparallel, the software defined networking (SDN) paradigm and the active stateful path computation element (PCE) are emerging as candidates for the control of next-generation optical networks. Such architectures are also particularly suitable in the case of defragmentation since they enable the controller to trigger reoptimization procedures. In this paper, we investigate defragmentation in the presence of super-channels, at both the control and data planes. We propose and experimentally demonstrate a technique based on a periodically poled lithium niobate waveguide to achieve both frequency conversion and defragmentation in elastic (or flex-grid) optical networks. Its peculiarity is that it is suitable for super-channels because it avoids detrimental subcarrier overlapping during a frequency shift. SDN with the OpenFlow protocol is discussed for the control of such operations, as well as the active stateful PCE and generalized multi-protocol label switching (GMPLS). The frequency conversion and defragmentation techniques are demonstrated in a lab trial considering a 200 Gb/s super-channel and extended OpenFlow for the control plane. No loss of data is experienced.

An Integrated IP-MPLS Architecture for Next Generation Networks

Next Generation Networks (NGN) is a strategy to achieve the vision of next-generation services for the delivery of quad play data, voice and video anywhere and anytime virtually across any access technology. It integrates the services of 2G/3G/4G Networks including IPv4 and IPv6 and incorporates the services of traditional networks into a single service platform with the usage of Multi-Protocol Label Switching (MPLS). Much work has been reported by researchers to integrate MPLS technology into IP networks. But, not much progress has been made so far. In this paper, a novel integrated IP-MPLS Architecture is proposed, which provides IP-integration, end-to-end quality of service, security, scalability, resiliency, and management enhancements for deploying data, voice, and video services. Test bed has been established for testing the performance of the proposed architecture.

Two Heuristics for Calculating a Shared Risk Link Group Disjoint Set of Paths of Min-Sum Cost

A shared risk link group (SRLG) is a set of links which share a common risk of failure. Routing protocols in Generalized MultiProtocol Label Switching, using distributed SRLG information, can calculate paths avoiding certain SRLGs. For single SRLG failure an end-to-end SRLG-disjoint path pair can be calculated, but to ensure connection in the event of multiple SRLG failures a set with more than two end-to-end SRLG-disjoint paths should be used. Two heuristic, the Conflicting SRLG-Exclusion Min Sum (CoSE-MS) and the Iterative Modified Suurballes's Heuristic (IMSH), for calculating node and SRLG-disjoint path pairs, which use the Modified Suurballes's Heuristic, are reviewed and new versions (CoSE-MScd and IMSHd) are proposed, which may improve the number of obtained optimal solutions. Moreover two new heuristics are proposed: kCoSE-MScd and kIMSHd, to calculate a set of $$k$$k node and SRLG-disjoint paths, seeking to minimize its total cost. To the best of our knowledge these heuristics are a first proposal for seeking a set of $$k\, (k>2)$$k(k>2) node and SRLG-disjoint paths of minimal additive cost. The performance of the proposed heuristics is evaluated using a real network structure, where SRLGs were randomly defined. The number of solutions found, the percentage of optimal solutions and the relative error of the sub-optimal solutions are presented. Also the CPU time for solving the problem in a path computation element is reported.

A Rapid Switching Technology of IP Data Packet Based on Multi-Protocol

The rapid development of network raise the role of WAN. As a large-scale backbone network, the failure of network components can lead to huge loss of data and revenue. How to improve the data switching speed and Quality of Service of network data is more and more important problem which Internet Server Provides cared. Multi-Protocol Lable Switching (MPLS) is a new WAN technology which is currently being standardized by IETF. This paper analysise the architecture of MPLS and describe the mechanism of label switching protocol. In addition, this study analyses the encapsulation of data packet at the Label Switching Routers which is on the boundary of MPLS network. A Label Switching Path (LSP) is built by Label Distribute Protocol in core network. A conclution of “one time routed, more times switching” routed was reached.

Research on Simulation of Satellite MPLS Network in OPNET

Multi-Protocol Label Switching has provided a perfect framework for the joint optimization of IP service. Satellite interconnection becomes an important candidate for the construction of next generation satellite network. This paper aims at researching satellite MPLS network. Two typical simulation scenarios are simulated in OPNET to test label switching, label distribution and quality of service(QoS)[1] guarantee of satellite MPLS network. Finally, the feasibility of satellite MPLS network and its capability of improving QoS are verified.

A Delay-Oriented Prioritization Policy Based on Cooperative Lossless Buffering in PTN Domains

New kinds of services and data flows, such as cloud computing, server virtualization, or quality of service (QoS)-aware Internet services, have led to higher demands on network resources. Thus, they have also led to increased bandwidth consumption and unexpected congestion, especially in backbones. In this article a novel proposal is studied, with the aim of improving the performance of delay-sensitive flows. The congestion impact on those QoS-aware flows that require a high level of reliability and delay is analyzed. This management proposal has been implemented on multiprotocol label switching transport profile (MPLS-TP), which is a packet transport networks technology that provides QoS by means of flow differentiation in Internet backbones. In order to improve performance in congested networks, a guarantee of service is proposed. It allows local recovery of lost traffic of MPLS-TP privileged flows, and in order to fulfill the requirements for implementation on MPLS-TP, a minimum set of extensions to RSVP-TE has also been proposed to provide self-management capable routes. Finally, in this paper we have carried out a performance improvement measurement by means of an analytical model and simulations.

Performance Evaluation of VoIP in MPLS network using NS-2

To evaluate and enhance the performance of the High-Speed Data networks some study on network technology is required to be done, it also require to simulate and verify the results and suggests the better solutions for High-Speed Data networks like Real-time Data network (Multimedia data, Voice data). Multiprotocol Label Switching (MPLS) is an emerging technology and plays an important role in the next generation networks by providing Quality of service (QoS). It overcomes the limitations like excessive delays and high packet loss of IP networks by providing scalability and congestion control. The key feature of MPLS is its Traffic Engineering (TE) which is used for effectively measuring the performance of the networks and efficient utilization of network resources. MPLS provides lower network delay, efficient forwarding mechanism, scalability and predictable performance of the services which makes it more suitable for implementing real-time applications such as Voice and video. In this paper performance of Voice over Internet Protocol (VoIP) application is implemented in MPLS network and conventional Internet Protocol (IP) network. NS-2 (Network Simulater-2) is used to simulate the both networks and the comparison is made based on the metrics such as Voice packet delay, voice packet lost probability, throughput, voice packet send and received. The simulation results are analyzed and it shows that MPLS based solution provides better performance in implementing the VoIP application.The simulated results in the form of animations and graphs can be helpful for network operators or designers to determine the number of VoIP calls, to estimate the packet lose probability and other QoS parameters that can be estimated and evaluated for a given network by using NS-2 simulator.

Multirate Multiservice All-Optical Code Switched GMPLS Core Network Utilizing Multicode Variable-Weight Optical Code-Division Multiplexing

A multicode variable-weight (MCVW) technique is proposed for generalized multiprotocol label switching (GMPLS) optical networks in order to support multirate and integrated multimedia services. Under this technique, the number of simultaneously assigned codewords to each user is a function of the data rate of the service class, while quality-of-service differentiation is achieved using variable-weight codewords for each service class. The traffic behavior of the network is modeled using a multiservice loss model, and the probability density functions of the number of busy codes in the fiber link are obtained by the Kaufman–Roberts algorithm. In order to analyze the performance of the proposed multiservice multicode GMPLS optical network, several measures are derived and investigated, specifically, the bit-error rate, probability of degradation, blocking probability, and steady-state throughput. These performance measures are obtained for two different receiver structures, namely, correlation receivers with and without hard limiters. The performance of our optical GMPLS network, based on the multicode switching path, is compared with that of traditional optical GMPLS networks, based on the label switching path. The results show the superiority of the proposed technique when compared to traditional ones.

A heuristic approach for border node selection and traffic routing in multi-domain optical networks

In this article we present a heuristic for selecting a set of domain border nodes and an improved routing scheme to route intra- and inter-domain traffic with low blocking probability in multi-domain multi-rate optical networks. The selection of border nodes is based on topological parameters and on intra-domain traffic. The routing scheme is impairment- and bandwidth-aware and searches for the optimum lightpath through the domains that meets the connection requests based on an improved system of weights assigned to links. The traffic routing is based on the Backward-Recursive Path Computation Element (PCE)-based Computation (BRPC) procedure of the Internet Engineering Task Force (IETF), which means that domains inform only a set of shortest paths that are strictly essential to route the traffic. The network model fits the Automatically Switched Optical Network (ASON) architecture of the International Telecommunication Union (ITU-T) and the operational management of the network is based on the procedures of the IETF Generalized Multi-Protocol Label Switching (GMPLS) control plane. Numerical results from computational simulations show the versatility and usefulness of the proposed scheme, which improves the blocking probability of inter-domain traffic by up to 41.5% compared to a scheme reported in the literature.

Multiprotocol Label Switching in Vehicular Ad hoc Network for QoS

Vehicular Ad hoc Networks (VANET) provides a wireless communication between vehicles. VANET applications play a significant role in the transportation sector such as vehicle safety, environmental efficiency, traffic control etc. Vehicular Ad hoc network is a subclass of Mobile Ad hoc networks. One of the main concerns in transportation is quality of service (QoS). In VANET, various solutions proposed for quality of services and these solutions applied on layer 2 and layer 3. In this paper, we proposed a Multiprotocol Label Switching. MPLS is an efficient and effective technique that forwards the packets across the network by using the contents of the labels attached to the IP packets. MPLS is known to be a layer 2.5 technology because it supports both data link layer or layer-2 and layer-3. The use of MPLS as backbone networks has increased over the past few years as compared to traditional IP networks, which were based on Iayer-2 technologies. MPLS is a forwarding method used for backbone network. In this paper, we improve quality of service in term of delay, packet loss and throughput in highway areas.

MPLS와 멀티캐스트 융합을 통한 Video Stream 방송 전송 최적화

QoS techniques and transmitted in real-time communication with the advancement of technology a variety of applications and services are available these days, mobile devices bogeuphwa LTE technology to the development of multimedia services with high quality can be realized. In order to satisfy this condition simply with a router with an increased bandwidth expansion by considering the increase in the routing table of the network scalability problems included. Burst traffic data to be distributed according to the environment is to be centered . To do this, the destination -based routing method to transmit the current paper -based (Source routing) routing settings are required. In this paper, published by the IETF , IP switching system based on standardized protocol Label Switching Multi-Protocol Label Switching (MPLS) network by using the existing Best Effect is difficult to guarantee QoS for multimedia transmission in MPLS network environment using optimized QoS guarantees to transmit the multicast.

Dynamic and Adaptive Control Plane Solutions for Flexi-Grid Optical Networks Based on Stateful PCE

Adaptive flexi-grid optical networks should be able to autonomously decide where and when to dynamically setup, reoptimize, and release elastic optical connections, in reaction to network state changes. A stateful path computation element (PCE) is a key element for the introduction of dynamics and adaptation in generalized multiprotocol label switching (GMPLS)-based distributed control plane for flexi-grid DWDM networks (e.g., global concurrent reoptimization, defragmentation, or elastic inverse-multiplexing), as well as for enabling the standardized deployment of the GMPLS control plane in the software defined network control architecture. First, this paper provides an overview of passive and active stateful PCE architectures for GMPLS-enabled flexi-grid DWDM networks. A passive stateful PCE allows for improved path computation considering not only the network state (TED) but also the global connection state label switched paths database (LSPDB), in comparison with a (stateless) PCE. However, it does not have direct control (modification, rerouting) of path reservations stored in the LSPDB. The lack of control of these label switched paths (LSPs) may result in the suboptimal performance. To this end, an active stateful PCE allows for optimal path computation considering the LSPDB for the control of the state (e.g., increase of LSP bandwidth, LSP rerouting) of the stored LSPs. More recently, an active stateful PCE architecture has also been proposed that exposes the capability of setting up and releasing new LSPs. It is known as active stateful PCE with instantiation capabilities. This paper presents the first prototype implementation and experimental evaluation of an active stateful PCE with instantiation capabilities for the GMPLS-controlled flexi-grid DWDM network of the ADRENALINE testbed.

Software-defined optical networks (SDONs): a survey

This paper gives an overview of software-defined optical networks (SDONs). It explains the general concepts on software-defined networks (SDNs), their relationship with network function virtualization, and also about OpenFlow, which is a pioneer protocol for SDNs. It then explains the benefits and challenges of extending SDNs to multilayer optical networks, including flexible grid and elastic optical networks, and how it compares to generalized multi-protocol label switching for implementing a unified control plane. An overview on the industry and research efforts on SDON standardization and implementation is given next, to bring the reader up to speed with the current state of the art in this field. Finally, the paper outlines the benefits achieved by SDONs for network operators, and also some of the important and relevant research problems that need to be addressed.

Leveraging MPLS Backup Paths for Distributed Energy-Aware Traffic Engineering

Backup paths are usually pre-installed by network operators to protect against single link failures in backbone networks that use multi-protocol label switching. This paper introduces a new scheme called Green Backup Paths (GBP) that intelligently exploits these existing backup paths to perform energy-aware traffic engineering without adversely impacting the primary role of these backup paths of preventing traffic loss upon single link failures. This is in sharp contrast to most existing schemes that tackle energy efficiency and link failure protection separately, resulting in substantially high operational costs. GBP works in an online and distributed fashion, where each router periodically monitors its local traffic conditions and cooperatively determines how to reroute traffic so that the highest number of physical links can go to sleep for energy saving. Furthermore, our approach maintains quality-of-service by restricting the use of long backup paths for failure protection only, and therefore, GBP avoids substantially increased packet delays. GBP was evaluated on the point-of-presence representation of two publicly available network topologies, namely, GEANT and Abilene, and their real traffic matrices. GBP was able to achieve significant energy saving gains, which are always within 15% of the theoretical upper bound.

Code Switching in the Toba Batak Wedding Ceremony

The aims are to find out: 1) the types of code switching used in the Toba Batak wedding ceremony, 2) how the participants switch language in the process of Toba Batak wedding ceremony, and 3) reason why the participants switch language in the process of Toba Batak wedding ceremony. The data were obtained from the utterances of participants which contain code switching during the process of Toba Batak wedding ceremony precisely in Marhaban, replying and exchanging the verses of rhymes, exchanging of Tepak, and upah-upah stages. They were analyzed by using some steps as normally applied in descriptive qualitative method. The instruments of data collection were audio visual recorder. The findings of the study indicate that; a) Three types of code switching found namely intrasentential, intersentential and tag switching b) Participants in Toba Batak wedding ceremony mix some languages based on participants’ tribes which involved in the process of Toba Batak wedding ceremony and they also adjust the situation and the condition of the people c) Three reasons of code switching during the process of Toba Batak wedding ceremony namely the differences of family’s tribes, religion factor and place of wedding ceremony be held. Keywords: Code Switching; Toba Batak; Traditional Marriage

ANALISA PERBANDINGAN WAKTU DAN KECEPATAN TRANSFER PADA MULTI PROTOCOL LABEL SWITCHING (MPLS) DENGAN VIRTUAL PRIVATE NETWORK (VPN) UNTUK PERPINDAHAN DOKUMEN PADA JARINGAN KOMPUTER

MPLS (Multi Protocol Label Switching) technology has been developed and mostly used by the service provider on their main network. Data packets which forwarded from one router to another router can also use VPN (Virtual Private Network) technology. VPNs were developed in the field of computer networks now have many variants, such as MPLS VPN and VPN which connects between computers or a LAN through a public network is the internet. The purpose of this final task is build a lab scale VPN network with MPLS technology use Mikrotik router RB 750GL and create a VPN connection to the STTA campus network passing the public internet. Then do a comparative analysis of the time required and the speed of transfer on both the network. The results of a comparative analysis between MPLS and VPN with the same file capacity, it appears that the MPLS network is faster in time speed and transfer speed

Continuous Monitoring of Smart Grid Devices Through Multi Protocol Label Switching

Data refreshment rate of a present power system is relatively slow and in some cases this slow refreshment rate may not be capable of providing information about dynamic state of power system devices. The use of multi protocol label switching based technique is one option to overcome this problem. A cost effective and simpler detection device is needed for condition monitoring and integrating the sensor signals into the smart grid monitoring system. Remote and on-line monitoring of ultra wide band partial discharge signal in a switch-yard is a new concept in smart grid technology that will help avoid damage of switchyard devices. It is possible to convert the radio frequency partial discharge signal into an equivalent milli-volt or milli-ampere output for remote or centralized monitoring of switchyard devices. Multi Protocol Label Switching based data transfer rate is faster than the conventional data transfer system of a power grid. In this paper a new and technically better method of on-line radio frequency partial discharge monitoring from a remote smart grid control room through multi protocol label switching is discussed.

Migrate to IPv6 on 6PE with MPLS-TE: Questions on Feasibility and Reluctance in Deployment?

Due to the exhaustion of IPv4 addresses, the transition to IPv6 has already begun using various transition mechanisms. In this paper comparison between two transition mechanism 6PE and 6to4 tunneling over MPLS (Multiprotocol Label Switching) based network has been performed. The experimental platform used is based on GNS3/Dynagen using emulated routers on which multiple TCP and UDP flows were generated between separated IPv6 network traversing through IPv4 based core. Traffic were generated using both transition mechanism and are compared to native IPv4 based MPLS network. Performance metric used are end-to-end delay, jitter and throughput, these parameters are also analyzed statistically using ANOVA, F-Test and T-Test to support a conclusion. Further, MPLS Traffic-Engineering (TE) using RSVP-TE signalling is applied, describing the implementation and performance test and analysis of TE tunnels on 6PE for IPv6 traffic. The same test-bed is used to implement and observe MPLS-TE behavior and throughput of 6PE based MPLS-TE to that of native IPv4 based MPLS-TE. Concluding, throughput of 6PE and 6to4 is around 99% and 96%, respectively, as compared to that of native IPv4.

Architecture of an Enhanced Packet-Optical Transport System

This paper describes an upcoming technology, currently under development, based on packet-optical transport. We present an enhanced packet optical transport system (ePOTS) to cope with the CAPEX/OPEX issues of current networks, and explain the system’s major features, its potential services, and network deployment scenarios. Our results show that ePOTS can provide multimedia services efficiently and reduce the network cost by around one-third that of a multiprotocol label switching network.

Experimental performance evaluation of software defined networking (SDN) based data communication networks for large scale flexi-grid optical networks.

Software defined networking (SDN) has become the focus in the current information and communication technology area because of its flexibility and programmability. It has been introduced into various network scenarios, such as datacenter networks, carrier networks, and wireless networks. Optical transport network is also regarded as an important application scenario for SDN, which is adopted as the enabling technology of data communication networks (DCN) instead of general multi-protocol label switching (GMPLS). However, the practical performance of SDN based DCN for large scale optical networks, which is very important for the technology selection in the future optical network deployment, has not been evaluated up to now. In this paper we have built a large scale flexi-grid optical network testbed with 1000 virtual optical transport nodes to evaluate the performance of SDN based DCN, including network scalability, DCN bandwidth limitation, and restoration time. A series of network performance parameters including blocking probability, bandwidth utilization, average lightpath provisioning time, and failure restoration time have been demonstrated under various network environments, such as with different traffic loads and different DCN bandwidths. The demonstration in this work can be taken as a proof for the future network deployment.