MPLS Research Articles

Quality of Service Architecture for Internet of Things and Cloud Computing

of Things (IoT) and Cloud Computing paradigm is a next wave in the era of computing and it has been identified as one of the emerging technologies in the field of Computer Science and Information Technology. The complementarity of these two technologies play a major role in accessing any services and applications anywhere, anytime in the smart environment. But from the literature study, it has been understood that the integration of IoT and cloud computing is in its infantile phase and it has not been extended to all application domains due to its inadequate quality of service architecture. Hence, in this paper a novel, quality of service architecture for internet of things and cloud computing is proposed. This architecture facilitates the public to have an easy access over diversified smart applications and services distributed in the cloud with one IoT enabled Intelligent Smart Card (ISC) through mobile devices with assured quality of service. The cloud services are integrated and connected through an Internet Protocol / Multi Protocol Label Switching (IP/MPLS) core System. The QoS requirements are met with differentiated services. The performance of the proposed architecture is tested by establishing a test bed in a simulated environment.

A novel stateful PCE-cloud based control architecture of optical networks for cloud services

The next-generation optical network is a service oriented network, which could be delivered by utilizing the generalized multi-protocol label switching (GMPLS) based control plane to realize lots of intelligent features such as rapid provisioning, automated protection and restoration (P&R), efficient resource allocation, and support for different quality of service (QoS) requirements. In this paper, we propose a novel stateful PCE-cloud (SPC) based architecture of GMPLS optical networks for cloud services. The cloud computing technologies (e.g. virtualization and parallel computing) are applied to the construction of SPC for improving the reliability and maximizing resource utilization. The functions of SPC and GMPLS based control plane are expanded according to the features of cloud services for different QoS requirements. The architecture and detailed description of the components of SPC are provided. Different potential cooperation relationships between public stateful PCE cloud (PSPC) and region stateful PCE cloud (RSPC) are investigated. Moreover, we present the policy-enabled and constraint-based routing scheme base on the cooperation of PSPC and RSPC. Simulation results for verifying the performance of routing and control plane reliability are analyzed.

GMPLS/PCE-Controlled Multi-Flow Optical Transponders in Elastic Optical Networks [Invited

Elastic optical networks aim at considerably improving network spectrum efficiency by using a flexible grid, while traditional optical transport networks operate with fixed frequency spacing. In such flexible networks, connections are accommodated into so-called “frequency slots,” which are dynamically established depending on client data rates and selected signal modulation formats. Key enablers to develop such a network infrastructure are bandwidth variable optical cross-connects (BV-OXCs) and BV transponders. For the latter, a multi-flow optical transponder (MF-OTP) is being considered as an appealing solution because of its support of high-rate super-channels as well as its elasticity, where optical connections can be reconfigured flexibly according to the required traffic requests. The dynamic selection (path computation) and automatic network configuration of both optical spectrum and MF-OTP resources are handled by a control plane entity. Herein, a distributed Generalized Multi-Protocol Label Switching (GMPLS) control plane combined with an active Path Computation Element (PCE) are adopted for the dynamic instantiation of flexgrid optical connections. To fully control the MF-OTP’s attributes and capabilities, specific extensions are required for both GMPLS routing and signaling.We propose and experimentally validate such extensions by considering two information models: partial and full. The difference between the models lies in information related to optical spectrum status (carried by the full model) on the MF-OTP interfaces attached to the BV-OXCs. Furthermore, a novel online routing, spectrum, and modulation assignment (RSMA) algorithm is conceived. The RSMA adopts both models to compute paths by trying to optimize the spectral link and MF-OTP resources when dynamically serving flexgrid connections. The experimental evaluation compares the models' attained RSMA performance with respect to the blocking probability as well as the setup and path computation delays.

Multidomain Network Hypervisor for Abstraction and Control of OpenFlow-Enabled Multitenant Multitechnology Transport Networks [Invited

A virtualization architecture is presented for deploying multitenant virtual networks on top of multitechnology optical networks. A multidomain network hypervisor (MNH) and a multidomain SDN orchestrator (MSO) are introduced with this purpose. TheMNHprovides an abstract view of each virtual network and gives control of it to each independent customer SDN controller. The MNH is able to provide virtual networks across heterogeneous control domains (i.e., generalized multiprotocol label switching and OpenFlow) and transport technologies (i.e., optical packet switching and elastic optical networks). The MSO is responsible for providing the necessary end-toend connectivity. We have designed, implemented, and experimentally evaluated the MNH and MSO in an international testbed across Spain, UK, Germany, and Japan.

Control and Orchestration of Multidomain Optical Networks With GMPLS as Inter-SDN Controller Communication [Invited

Emerging use cases, such as the orchestration of heterogeneous domains or the interconnection of remote data centers, require the design of new network control, management, and orchestration architectures that are adapted to the requirements associated with end-to-end services. This heterogeneity, stemming from actual deployments, is related to the involved data and control technologies or due to network segmentation. It is acknowledged that, in these scenarios, the deployment of a single software- defined networking (SDN) controller may not be practical or may have fundamental limitations, in terms of either scalability, complexity, or interoperability. To address this trend, and as a means to cope with the complexity growth, research in this area is considering the concept of SDN orchestration (the coordinated control of heterogeneous systems), abstraction (the selection of entityrelevant attributes), and the use of multiple controllers, commonly arranged in hierarchical or flat configurations. In this paper, we consider a hybrid approach combining elements from distributed control with elements from centralized control, relying on the concepts of abstraction and aggregation and hierarchical traffic engineering (TE). We propose a multidomain and multivendor network control architecture organized in layers, the abstract network layer and the control-specific layer, resulting in a mesh of generic SDN controllers that use generalized multiprotocol label switching (GMPLS) protocols as their east/west interfaces (open shortest path first TE and Resource Reservation Protocol with extensions for TE as inter- SDN controller communications protocols), forming an abstracted topology. To validate the approach, and to evaluate factors such as end-to-end network service deployment delay or control overhead, the proposed architecture is implemented and validated in a control plane testbed. While emphasis is given to the control of optical (flexi-grid) networks, the proposed approach can be generalized to other transport technologies.

Performance Evaluation of IPv4 and IPv6 over MPLS using OPNET

Over the last two decades, we have witnessed a rapid deployment of real-time applications on the Internet and many research works focus on Quality of Service (QoS), in particular using IPv4 (Internet Protocol Version 4). The inevitable exhaustion of the remaining IPv4 address pool has become progressively evident and as a result the evolution of Internet Protocol (IP) continues leading to the deployment of IPv6 QoS. Today, there is limited experience in the deployment of QoS for IPv6 traffic in MPLS backbone networks in conjunction with DiffServ (Differentiated Services) support. DiffServ itself does not have the ability to control the traffic flow whereas MPLS Traffic Engineering (TE) can control the traffic and can set up end-to-end routing path before data can be forwarded. Multi-Protocol Label Switching (MPLS) plays a key role in next generation networks by delivering QoS and traffic engineering features which is helpful in managing traffic when some links or paths are under and/or over utilized This paper presents a QoS performance study of some applications such as voice, video conferencing, mail and web over DiffServ with MPLS in IPv4/IPv6 networks using Optimized Network Engineering Tool (OPNET). The effectiveness of DiffServ and MPLS integration in IPv4/IPv6 network is illustrated and analyzed.

H2S-induced S-sulfhydration of pyruvate carboxylase contributes to gluconeogenesis in liver cells

BackgroundCystathionine gamma-lyase (CSE)-derived hydrogen sulfide (H2S) possesses diverse roles in the liver, affecting lipoprotein synthesis, insulin sensitivity, and mitochondrial biogenesis. H2S S-sulfhydration is now proposed as a major mechanism for H2S-mediated signaling. Pyruvate carboxylase (PC) is an important enzyme for gluconeogenesis. S-sulfhydration regulation of PC by H2S and its implication in gluconeogenesis in the liver have been unknown. MethodsGene expressions were analyzed by real-time PCR and western blotting, and protein S-sulfhydration was assessed by both modified biotin switch assay and tag switch assay. Glucose production and PC activity was measured with coupled enzyme assays, respectively. ResultsExogenously applied H2S stimulates PC activity and gluconeogenesis in both HepG2 cells and mouse primary liver cells. CSE overexpression enhanced but CSE knockout reduced PC activity and gluconeogenesis in liver cells, and blockage of PC activity abolished H2S-induced gluconeogenesis. H2S had no effect on the expressions of PC mRNA and protein, while H2S S-sulfhydrated PC in a dithiothreitol-sensitive way. PC S-sulfhydration was significantly strengthened by CSE overexpression but attenuated by CSE knockout, suggesting that H2S enhances glucose production through S-sulfhydrating PC. Mutation of cysteine 265 in human PC diminished H2S-induced PC S-sulfhydration and activity. In addition, high-fat diet feeding of mice decreased both CSE expression and PC S-sulfhydration in the liver, while glucose deprivation of HepG2 cells stimulated CSE expression. ConclusionsCSE/H2S pathway plays an important role in the regulation of glucose production through S-sulfhydrating PC in the liver. General significanceTissue-specific regulation of CSE/H2S pathway might be a promising therapeutic target of diabetes and other metabolic syndromes.

SDN orchestration for dynamic end-to-end control of data center multi-domain optical networking

New and emerging use cases, such as the interconnection of geographically distributed data centers (DCs), are drawing attention to the requirement for dynamic end-to-end service provisioning, spanning multiple and heterogeneous optical network domains. This heterogeneity is, not only due to the diverse data transmission and switching technologies, but also due to the different options of control plane techniques. In light of this, the problem of heterogeneous control plane interworking needs to be solved, and in particular, the solution must address the specific issues of multi-domain networks, such as limited domain topology visibility, given the scalability and confidentiality constraints. In this article, some of the recent activities regarding the Software-Defined Networking (SDN) orchestration are reviewed to address such a multi-domain control plane interworking problem. Specifically, three different models, including the single SDN controller model, multiple SDN controllers in mesh, and multiple SDN controllers in a hierarchical setting, are presented for the DC interconnection network with multiple SDN/ OpenFlow domains or multiple OpenFlow/ Generalized Multi-Protocol Label Switching (GMPLS) heterogeneous domains. In addition, two concrete implementations of the orchestration architectures are detailed, showing the overall feasibility and procedures of SDN orchestration for the end-to-end service provisioning in multi-domain data center optical networks.

On the performance of online and offline green path establishment techniques

Abstract To date, significant effort has gone into designing green traffic engineering (TE) techniques that consolidate traffic onto the minimal number of links/switches/routers during off-peak periods. However, little works exist that aim to green Multi-Protocol Label Switching (MPLS) capable networks. Critically, no work has studied the performance of green label switched paths (LSPs) establishment methods in terms of energy savings and acceptance rates. Henceforth, we add to the current state-of-the-art by studying green online and offline (LSP) establishment methods. Online methods rely only on past and current LSP requests while offline ones act as a theoretical benchmark whereby they also have available to them future LSP requests. We introduce a novel metric that takes into account both energy savings and acceptance rates. We also identify a new simpler heuristic that minimizes energy use by routing source–destination demands over paths that contain established links and require the fewest number of new links. Our evaluation of two offline and four online LSP establishment methods over the Abilene and AT&T topologies with random LSP setup requests show that energy savings beyond 20 % are achievable with LSP acceptance rates above 90 %.

The Efficiency Test of Additional Multi Protocol Label Switching Network Protocol Over Open Shortest Path First Network Using Graphic Network Simulator 3

Technological developments in the field of fiber optic telecommunications with the media of the backbone network is faster in comparison with other technologies. In the process, the telecommunications industry use the metro ethernet configuration with Multi Protocol Label Switching (MPLS) network and Open Shortest Path First (OSPF) as the backbone network. This study aims to answer the question of how much the effect of adding the MPLS network protocol on OSPF network. So from this research can be known the value of the efficiency of the addition MPLS network protocol on OSPF network based on network performance using a software simulator GNS3 as its backbone through a step-test. From the test results concluded that based on the delay by the load, MPLS makes network performance more efficient by 67.04%, based on the packet loss and link failure conditions, MPLS makes network performance more efficient by 1.1%, but based on the no-load delay, OSPF has more efficient network performance by 41.96%, and based on the transfer rate, OSPF has a more efficient network performance by 5.2%, to delay normal conditions both have a performance with an average value of 0% packet loss. DOI: http://dx.doi.org/10.11591/telkomnika.v15i1.7600

Using Stuffed Quadratic Congruence Codes for SAC Labels in Optical Packet Switching Network

While optical codes in optical code-division multiple access (OCDMA) has been extensively investigated, research of optical coding labels in optical multi-protocol label switching (MPLS) network is relatively unexplored. This paper studies optical labels with spectral-amplitude coding (SAC) for optical packet switching (OPS) network. The research focuses on implementing two different codes in optical labels: stuffed quadratic congruence (SQC) codes and M-sequence codes. Label-error rate (LER) is quantified to ascertain the influence of code pattern on system performance. The findings suggest that SQC coded label can support more numbers for label stacking, due to its very low cross-correlation value.

Maximally node and SRLG-disjoint path pair of min-sum cost in GMPLS networks: a lexicographic approach

Path protection is a fast and capacity-efficient approach for increasing the availability of end-to-end connections. However, sometimes it is not possible to obtain a fully disjoint path pair. In this case, it may be admissible to consider a path pair which is as disjoint as possible, and thus provide the best (in a certain sense) level of the single-fault protection that can be ensured using this type of approach. A shared risk link group (SRLG) is a group of links which have a common risk of failure. Two new heuristics for solving the min-sum maximally node and SRLG-disjoint path pair are presented. The relative performance of the new heuristics and also of two other previously proposed heuristics is evaluated using four different networks. Results, regarding accuracy and execution time of the studied heuristics, show that one of the new proposed algorithms can be a good compromise for use in the Generalized Multi-protocol Label Switching control plane.

Corporate Network Analysis with IPTV Traffic Insertion

This paper presents studies about Internet Protocol Television (IPTV) technology starting with its motivation that led to its birth and its great and current application. The article theoretical basis will present the description of mechanisms, standards and main protocols used to ensure a quality of service needed to the deployment of IPTV applications. Among them, we will mention Multiprotocol Label Switching (MPLS). It will be made a case study, including a corporate network of a large a mining company, which simulates the core of a provider network between data concentrator branches. The aim of this simulation is to analyze the network behavior after ITPV traffic insertion and serve as a basis to obtain conclusions about the possibility of developing new applications that use this technology.

IPv6와 IPv4 환경에서 IPTV 전송 최적화 위한 SDN을 응용한 MPLS

ABSTRACT SDN (Software Defined Network) technology, hardware and network control functions should be separated independently of existing switches or routers and data transfer functions and are also refers to a separate network architecture that can develop and run. When planning a network and designed to reflect the network control function by applying the SDN may reflect the resources efficiently. In this study, one people suggest Applications SDN, which offer an absolutely necessary part of a coded program that combines the benefits of the existing IOS (Combined Benefits) applying the model to complete the Controller part through the MPLS IOS. The OpenFlow Controller is a command to the router LER(Label Edge Router), and transmits the packet in accordance with the command to the destination according to the EXP bit. To configure TCP / IP to the IOS through the optimized coding. Using the OpenFlow protocol controller transmits an encapsulation header as defined in the MPLS packet. 키워드 :

Proposal and analysis of integrated PTN architecture in the mobile backhaul to improve the QoS of HetNets

The rapid progress made in mobile device technologies has implied that the access network must evolute and develop new strategies to satisfy the requirements of the users. Heterogeneous network (HetNet) allows for a flexible deployment strategy and offers economically viable solutions to improve network scalability and indoor coverage. This emerging topic has caught the attention of the research community and the industry because of the importance of these networks to satisfy the demand of data services. To provide this demand, different parameters of quality of service (QoS) must be satisfied. In this paper, we present a study on recent advances and open research issues on Mobility Protocols in conjunction with Multi-Protocol Label Switching (MPLS)-based packet transport networks (PTN) to provide QoS in wireless heterogeneous networks. Various mobile management protocols and their interaction with the mobile backhaul and packet core network are briefly introduced. A new architecture called Integrated Proxy Mobile MPLS-TP (IPM-TP) is also outlined to reduce the signalling cost and improve the QoS in HetNets with high rates of mobility.

Strategies for optical transport network recovery under epidemic network failures

The current trend in deploying automatic control plane solutions for increased flexibility in the optical transport layer leads to numerous advantages for both the operators and the customers, but also pose challenges related to the stability of the network and its ability to operate in a robust manner under different failure scenarios. This work evaluates two rerouting strategies and proposes four policies for failure handling in a connection-oriented optical transport network, under generalized multiprotocol label switching control plane. The performance of the strategies and the policies are evaluated under multiple correlated large-scale failures. We employ the Susceptible---Infected---Disabled epidemic failure spreading model and look into possible trade-offs between resiliency and resource efficiency. Via extensive simulations, we show that source rerouting outperforms on-site rerouting, and that there exist a clear trade-off between policy performance and network resource consumption, which must be addressed by network operators for improved robustness of their transport infrastructures. Applying proactive methods for avoiding areas where epidemic failures spread results in 50 % less connections requiring recovery, which translates in improved quality of service to customers and lower recovery expenses for the network operator.

Multi-Layer High-Speed Network Design in Mobile Backhaul Using Robust Optimization

The multi-layer network design problem and the mobile backhaul problem are both interesting from the perspective of choosing the correct technology and protocol as well as choosing the appropriate node architecture to meet a wide variety of overlay traffic demands. Network operators encounter two variants of the multi-layer/backhaul problem: 1) For a given set of uncertain traffic demands, which set of technologies would minimize the network cost? 2) Would these technology choices be invariant to the changing traffic demands? This problem of technology choice can essentially be abstracted to a switching and grooming problem with the added complexity of unknown traffic demands, which at best may be approximated to some known statistical parameters. To solve this complex switching and grooming problem, our goal is to make use of the theory of robust optimization with the assumption of known boundary conditions on traffic. We present a comprehensive optimization model that considers technology choices in terms of protocols, physical layer parameters, link boundary conditions, and transmission layer constraints. Validated by simulations, our model shows the stand-off conditions between various technologies and how a network operator must take proactive steps to be able to meet requirements of the next-generation networks and services. Our main result showcases network design using two technology alternatives [1) Multi-Protocol Label Switching (MPLS) + Optical Transport Network (OTN) + Reconfigurable Optical Add–Drop Multiplexer (ROADM) and 2) Carrier Ethernet (CE) + OTN + ROADM] and the effect of robustness on these choices. A heuristic is used for comparative purposes as well as to exhaustively model the dynamic case of brownfield networks.

IJARCCE - Computer and Communication Engineering

Quality of Service (QoS) in Real Time Applications such as video, voice, online gaming is becoming the major concern. In Today's Scenario Voice over Internet Protocol (VoIP) is an emerging service because of the benefits of this service. The most advantageous benefit which attracts many people using this service is the low cost. QoS is an important factor for the voice traffic. Internet Protocol (IP) network implements QoS in two ways i.e. Integrated Services (IntServ) and Differentiated Services (DiffServ) but still VoIP suffers from delay, voice echo, packets loss or Intermittent silent pauses. Multi Protocol Label Switching (MPLS) is a framework specified by IETF when used with IP increases its QoS. MPLS is used as an extension to IP. In this paper we define the MPLS QoS management and how it supports the IP QoS architecture.

OpenFlow and GMPLS Unified Control Planes: Testbed Implementation and Comparative Study

Finding an effective and simple unified control plane (UCP) for IP/dense wavelength division multiplexing multilayer optical networks is very important for network providers. Generalized multi-protocol label switching (GMPLS) has been in development for decades to control optical transport networks. However, it is extremely difficult to deploy in real operational products, as there is still much non-GMPLS-capable equipment. On the other hand, OpenFlow (OF), one of the most widely used software defined networking implementations, can be used as a UCP for packet and circuit switched networks [“Packet and circuit network convergence with OpenFlow,” in OFC/NFOEC, Mar. 2010]. In this paper, we propose and experimentally evaluate two solutions using OF to control both packet and optical networks (OpenFlow Messages Mapping and OpenFlow Extension). The overall feasibility of these solutions is assessed, and their performance is evaluated and compared with the GMPLS approach, using a custom-built simulator. Simulation results show that the OpenFlow Extension solution outperforms the OpenFlow Messages Mapping and GMPLS solutions.

On providing fast protection with remote loop-free alternates

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.