iINCREASING CUSTOMER BASE USING MPLS TECHNOLOGY IN YEMENNET

A Project PaperPresented to

The Center for Graduate StudiesMaster of Information Technology and Management

Taiz University, Taiz City, Republic of Yemen

In Partial Fulfillmentof the Requirements for the Degree of

Master of Information Technology and Management

byEng. Abutaleb Abdulrahman M.

Dr. Nelson MarcosFaculty Adviser

March 22, 2014

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Approval Sheet

This project hereto entitled:

INCREASING CUSTOMER BASE USING MPLS TECHNOLOGY IN YEMENNET

Prepared and submitted by Eng. Abdulrahman M. Abutaleb in partial fulfillment of therequirements for the degree of Master of Information Technology and Management has beenexamined and is recommended for acceptance and approval for ORAL EXAMINATION.

Dr. Nelson MarcosAdviser

Approved by the Committee on Oral Examination with a grade of PASSED on March 22,2014.

Dr. Mohammed A. EbrahimChair

Professor Vicente Pijano Professor Hans GeersMember Member

Professor Gerrit Versluis Professor Maartin LoojienMember Member

Accepted in partial fulfillment of the requirements for the degree of Master ofInformation Technology and Management.

Dr. Abdo Al-DaqafManaging DirectorCenter for Graduate StudiesTaiz University

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Abstract

YemenNet is the gateway of Yemen to Internet which was founded in 2001 and belongsto public sector by YT. Multi Protocol Label Switching (MPLS) is an emerging technologywhich transmits and delivers the Internet services with high transmission speed and lower delays.MPLS had been installed in 2009 in YemenNet to give a broadband services and Internet. Thekey feature of MPLS is its Traffic Engineering (TE), which is used for effectively managing thenetworks for efficient utilization of network resources. Due to lower network delay, efficientforwarding mechanism, scalability and predictable performance of the services provided byMPLS technology makes it more suitable for implementing real-time applications, such as voiceand video which should be implemented in YemenNet, and definitely would increase customerbase. In this project, the researcher simulated three tests using MPLS features QoS, TE, and FRRfor proving the performance and resiliency. The performance of Voice over Internet Protocol(VoIP), video and data (FTP) applications are compared between MPLS network andconventional Internet Protocol (IP) network (legacy network). OPNET modeler 14.5 is used tosimulate the networks and the comparison was made based on some performance metrics such asvoice jitter, voice packet end-to-end delay, voice delay variation, voice packet sent and received.

The simulation results were analyzed and showed that MPLS based solution providedbetter performance in implementing all applications. The results could help the top managementin YT and YemenNet to invest and cover all country with MPLS, and also implement real-timeapplications which absolutely increase customer base.

In this project, the results met all the project objectives, and gave a good roadmap tocare about customer by designing SLA and following the recommendations. YemenNet needsmore care from top managements in YT and Ministry of Telecommunication and InformationTechnology.

Keywords: Multi Protocol Label Switching (MPLS), Traffic Engineering (TE), Voice overInternet Protocol (VoIP), FRR, QoS, Optimized Network Engineering Tool (OPNET), andYemenNet.

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Acknowledgment

In the name of Allah, the most gracious and the most Merciful.

AND mention my prophet Mohammed (peace be upon him and his household).

First and foremost, I would like to give thanks to almighty ALLAH who blessed me withguidance and helped me for making this short period of educational journey a reality.

I want to extend my gratitude to my beloved parents, wife, & family for their heartfeltlove, support, and encouragement during my project work, in particular my father, my mother,my father-in-law and my mother-in-law for their kind love, encouragement, and advice.

I would also like to thank my supervisor, Dr. Nelson Marcos and the Government of theNetherlands through Delft Technological University, who helped me to make my dream cometrue after providing me with useful knowledge and directions on how to deal with Masters inIT&M.

I am pleased to thank Dr. Ali Naji Nosary , the DG of PTC Eng. Sadek Mousleh, Sir AliThabet, Sir Mohammed Alzamzami, Eng. Lutfi Bashareef, Eng. Hafiz Anwar, Eng. Amer Hazaand Eng. Yasser Alaimad for their support which helped me to feel relax and attain success. Also,thanks to all my Colleagues in YT.

Lastly, I would like to express my love and affection to my children, to whom I owe anapology for having been too busy throughout my Masters studies and research. And, specialthanks to my wife who has been supporting me morally.

And to all who, in one way or another, have helped me finish this endeavor, I offer mygratitude and thanks.

.dedicated to my daughter and son (Alyaa & Ali)

vTable of Contents

Approval Sheet ................................................................................................................................iiAbstract...........................................................................................................................................iiiAcknowledgment ............................................................................................................................ ivTable of Contents............................................................................................................................. vList of Tables ................................................................................................................................viiiList of Figures................................................................................................................................. ixChapter 1 THE PROJECT DESCRIPTION .................................................................................... 1

1.1 Project Description ............................................................................................................... 11.2 Overview of the Current Technology ................................................................................... 1

1.2.1 Some definition of terms ................................................................................................ 11.2.2 Problem Statement ......................................................................................................... 2

1.3 Project Objectives................................................................................................................. 21.3.1 General Objective........................................................................................................... 21.3.2 Specific Objectives......................................................................................................... 2

1.4 Scope and Limitations of the Project.................................................................................... 31.4.1 Scope .............................................................................................................................. 31.4.2 Limitations ..................................................................................................................... 3

1.5 Significance of the Project.................................................................................................... 31.6 Project Methodology ............................................................................................................ 4

1.6.1 Theoretical framework ................................................................................................... 41.6.2 Data gathering ................................................................................................................ 41.6.3 Data analysis .................................................................................................................. 51.6.4 Schedule of activities...................................................................................................... 5

Chapter 2 REVIEW OF RELATED LITERATURE ...................................................................... 62.1 Related Literature ................................................................................................................. 62.2 Theoretical Related Studies .................................................................................................. 82.3 Practical Related Studies .................................................................................................... 10

Chapter 3 THEORETICAL FRAMEWORK ................................................................................ 163.1 MPLS Introduction ............................................................................................................. 16

3.1.1 Why do network providers motivate for MPLS? ......................................................... 163.1.2 MPLS Combines Routing and Switching .................................................................... 163.1.3 MPLS Header and Label .............................................................................................. 173.1.4 Label Space .................................................................................................................. 183.1.5 Forward Equivalence Class (FEC) ............................................................................... 183.1.6 MPLS Domain.............................................................................................................. 203.1.7 MPLS Architecture ...................................................................................................... 22

3.2 MPLS Application.............................................................................................................. 233.2.1 QOS.............................................................................................................................. 233.2.2 Traffic Engineering (TE).............................................................................................. 24

3.3 MPLS LSP Working........................................................................................................... 243.4 Signaling Protocols in MPLS Network .............................................................................. 25

3.4.1 Label Distribution Protocol (LDP)............................................................................... 253.4.2 RSVP- TE..................................................................................................................... 263.4.3 Comparison of RSVP and CR-LDP ............................................................................. 27

3.5 MPLS QoS.......................................................................................................................... 283.5.1 Scheduling Mechanisms............................................................................................... 283.5.2 Scheduling WFQ....................................................................................................... 29

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3.5.3 DiffServ Basics ............................................................................................................ 303.6 MPLS TRAFFIC ENGINEERING (MPLS-TE) ................................................................ 32

3.6.1 Link Congestion ........................................................................................................... 323.6.2 Benefits of MPLS-TE................................................................................................... 323.6.3 Network Resiliency by Using MPLS TE ..................................................................... 33

3.7 OPNET Modeler 14.5......................................................................................................... 343.7.1 Why OPNET? .............................................................................................................. 343.7.2 OPNET Framework...................................................................................................... 353.7.3 Project Editor................................................................................................................ 353.7.4 The Node Editor ........................................................................................................... 363.7.5 The Process Model Editor ............................................................................................ 363.7.6 The Link Model Editor................................................................................................. 373.7.7 The Path Editor............................................................................................................. 373.7.8 The Packet Format Editor............................................................................................. 383.7.9 The Probe Editor .......................................................................................................... 383.7.10 The Simulation Sequence Editor................................................................................ 393.7.11 The Analysis Tool ...................................................................................................... 39

Chapter 4 The EXISTING SYSTEM ............................................................................................ 404.1 Description of YemenNet ................................................................................................... 40

4.1.1 YemenNet History........................................................................................................ 404.1.2 PTC Objectives ............................................................................................................ 404.1.3 YemenNet Vision......................................................................................................... 414.1.4 YemenNet Task............................................................................................................ 414.1.5 YemenNet position in YT ............................................................................................ 414.1.6 YemenNet (The Target Company)............................................................................... 424.1.7 The First Team of YemenNet in 2001.......................................................................... 434.1.8 YemenNet Logo ........................................................................................................... 434.1.9 The description of the Target business units ................................................................ 444.1.10 Organizational chart ................................................................................................... 44

4.2 The current situation and system of YemenNet.................................................................. 454.2.1 PDN (Data Transmission) Topology............................................................................ 454.2.2 IN (Internet Topology) ................................................................................................. 454.2.3 MPLS Topology in YemenNet..................................................................................... 46

4.3 YemenNet Services ............................................................................................................ 474.4 The problems with the existing system in YemenNet ........................................................ 48

Chapter 5 THE PROPOSED SOLUTION..................................................................................... 495.1 Overview of the Solution.................................................................................................... 495.2 Details of the Solution ........................................................................................................ 495.3 IP network and MPLS-TE .................................................................................................. 49

5.3.1 Assumptions ................................................................................................................. 495.3.2 Network Scenario......................................................................................................... 495.3.3 Methodology ................................................................................................................ 50

5.4 Fast Reroute Technique (FRR) as Network Resilience ...................................................... 615.4.1 Assumptions ................................................................................................................. 615.4.2 Methodology ................................................................................................................ 61

5.5 MPLS with Quality of Services (QoS) ............................................................................... 685.5.1 Assumptions ................................................................................................................. 685.5.2 Methodology ................................................................................................................ 68

Chapter 6 THE RESULTS AND OBSERVATIONS.................................................................... 776.1 The Results Explanations ................................................................................................... 77

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6.2 Service Level Agreement (SLA) ........................................................................................ 78Chapter 7 THE CONCLUSION AND RECOMMANDATIONS................................................. 81

7.1 Final assessment of the project ........................................................................................... 817.2 Answers the project objectives ........................................................................................... 817.3 The future improvements.................................................................................................... 837.4 YemenNet recommendations.............................................................................................. 837.5 Future Works ...................................................................................................................... 85

References...................................................................................................................................... 86Appendix A List of Abbreviations........................................................................................... 90Appendix B YemenNet Services ............................................................................................. 92Appendix C PTCs Approval Sheet ......................................................................................... 99Appendix D Curriculum Vitae............................................................................................... 100

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List of Tables

Table Page

Table 1: The Schedule of the Project Activities .............................................................................. 5Table 2: Reference Documents (MPLS Model /Release 14.5 Description. OPNETDocumentation., 2008)..................................................................................................................... 6Table 3: MPLS Label Format (Rosen, et al., 2001) ....................................................................... 17Table 4: MPLS Labels between Layer-2 and Layer-3 Headers..................................................... 17Table 5: DiffServ Marking(OPNET Technologies, Session 1806 Introduction to QoSMechanisms Technology Tutorials, 2004)..................................................................................... 31Table 6: The First Team of YemenNet in 2001............................................................................. 43Table 7: SLA Format ..................................................................................................................... 79

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List of Figures

Figure Page

Figure 1: MPLS Combines Routing and Switching (OPNET Technologies, Session 1801Introduction to MPLS Technology Tutorials, 2004, p. 8) ............................................................. 17Figure 2: MPLS Shim Header (Davie & Farrel, 2008).................................................................. 17Figure 3: Forward Equivalence Class (FEC)(OPNET Technologies, Session 1801 Introduction toMPLS Technology Tutorials, 2004, p. 16) .................................................................................... 18Figure 4: FTN (OPNET Technologies, Session 1801 Introduction to MPLS Technology Tutorials,2004) .............................................................................................................................................. 19Figure 5: ILM (OPNET Technologies, Session 1801 Introduction to MPLS Technology Tutorials,2004) .............................................................................................................................................. 19Figure 6: Ingress LER (OPNET Technologies, Session 1801 Introduction to MPLS TechnologyTutorials, 2004).............................................................................................................................. 20Figure 7: Egress LER (OPNET Technologies, Session 1801 Introduction to MPLS TechnologyTutorials, 2004).............................................................................................................................. 21Figure 8: Label Switch Router (LSR)(OPNET Technologies, Session 1801 Introduction to MPLSTechnology Tutorials, 2004).......................................................................................................... 21Figure 9: Label Switch Path (LSP)(OPNET Technologies, Session 1801 Introduction to MPLSTechnology Tutorials, 2004).......................................................................................................... 22Figure 10: Label stack.................................................................................................................... 22Figure 11: Architecture of MPLS(Imran, 2009, p. 23) .................................................................. 23Figure 12: MPLS Application and their Interaction (Imran, 2009, p. 31) ..................................... 23Figure 13: LSP in MPLS (OPNET Technologies, Simulation-based Analysis of MPLSTrafficEngineering A Case Study).......................................................................................................... 25Figure 14: LDP Messages (OPNET Technologies, Session 1801 Introduction to MPLSTechnology Tutorials, 2004).......................................................................................................... 26Figure 15: RSVP Messages (OPNET Technologies, Session 1801 Introduction to MPLSTechnology Tutorials, 2004).......................................................................................................... 26Figure 16: RSVP Examples(OPNET Technologies, Session 1801 Introduction to MPLSTechnology Tutorials, 2004).......................................................................................................... 27Figure 17: WFQ Principles (OPNET Technologies, Session 1806 Introduction to QoSMechanisms Technology Tutorials, 2004, p. 21)........................................................................... 29Figure 18: WFQ Mechanism (OPNET Technologies, Session 1806 Introduction to QoSMechanisms Technology Tutorials, 2004, p. 23)........................................................................... 29Figure 19: IP Datagram Lifecycle under QoS (OPNET Technologies, Session 1806 Introductionto QoS Mechanisms Technology Tutorials, 2004, p. 26) .............................................................. 30Figure 20: Shows an over utilized link(Imran, 2009, p. 33) .......................................................... 32Figure 21: Ingress Backup LSP (OPNET Technologies, Session 1511 Understanding MPLSModel Internals, 2004, p. 57)......................................................................................................... 33Figure 22: FRR (OPNET Technologies, Session 1511 Understanding MPLS Model Internals,2004, p. 59) .................................................................................................................................... 33Figure 23: The main window of OPNET Modeler 14.5 ................................................................ 34Figure 24: Workflow (Svensson & Popescu, 2003) ...................................................................... 35Figure 25: A network model built in the Project Editor (Svensson & Popescu, 2003) ................. 35Figure 26: Node Editor (Svensson & Popescu, 2003) ................................................................... 36Figure 27: Process Model Editor ................................................................................................... 36Figure 28: Link Model Editor ........................................................................................................ 37

xFigure 29: Path Editor.................................................................................................................... 37Figure 30: Packet Format Editor.................................................................................................... 38Figure 31: Probe Editor.................................................................................................................. 38Figure 32: Simulation Sequence Editor ......................................................................................... 39Figure 33: Analysis Tool ............................................................................................................... 39Figure 34: YemenNet position in Yemen Telecom ....................................................................... 41Figure 35: YemenNet logo............................................................................................................. 43Figure 36: Organizational Chart of YemenNet.............................................................................. 44Figure 37: Yemen Data Network (ATM, the legacy network) ...................................................... 45Figure 38: Internet Topology ......................................................................................................... 46Figure 39 : IP/MPLS Yemen National Network Topology ........................................................... 47Figure 40: YemenNet MPLS Network Topology.......................................................................... 50Figure 41: Methodology used in OPNET Modeler Scenario 1...................................................... 51Figure 42: MPLS Network with two static LSPs........................................................................... 51Figure 43: Application Definitions ................................................................................................ 52Figure 44: Profile Definitions ........................................................................................................ 52Figure 45: FEC Specifications ....................................................................................................... 53Figure 46: Traffic Trunk Profiles................................................................................................... 54Figure 47: FEC to LSP Mapping ................................................................................................... 54Figure 48: Choose Results ............................................................................................................. 55Figure 49: FTP Upload Response Time in Scenario 1................................................................... 57Figure 50: Voice Delay Results in Scenario 1 ............................................................................... 57Figure 51: Video Delay Results in Scenario 1............................................................................... 58Figure 52: Links Utilization Results in Scenario 1 ........................................................................ 58Figure 53: Links Utilization Results in Congestion Case in Scenario 1 ........................................ 59Figure 54: FTP Upload Response Time in Congestion Case in Scenario 1................................... 60Figure 55: Video Delay Results in Congestion Case in Scenario 1............................................... 60Figure 56: Voice Delay Results in Congestion Case in Scenario 1 ............................................... 61Figure 57: Methodology of FRR.................................................................................................... 62Figure 58: MPLS Network Using Bypass Tunnel (the red one).................................................... 62Figure 59: FRR Configurations in the Primary LSP...................................................................... 63Figure 60: Failure Recovery Object............................................................................................... 64Figure 61: LSP Traffic Reroute Time............................................................................................ 65Figure 62: LSP Traffic In............................................................................................................... 66Figure 63: The Delay Sensitive in both using Failure link or not.................................................. 67Figure 64: Methodology of QoS.................................................................................................... 68Figure 65: MPLS Network Map with using one LSP.................................................................... 69Figure 66: DSCP to EXP Mapping................................................................................................ 70Figure 67: Client FTP Upload Response Time with/without MPLS DiffServ .............................. 71Figure 68: Client FTP Upload Response Time with/without MPLS DiffServ in congestion........ 71Figure 69: Voice Calling Party Packet ETE Delay in normal traffic............................................. 72Figure 70: Voice Calling Party Packet ETE Delay in congestion traffic....................................... 72Figure 71: Voice Calling Party PDV in normal traffic .................................................................. 73Figure 72: Voice Calling Party PDV in congestion traffic ............................................................ 73Figure 73: IP interface WFQ Queue Delay Variation.................................................................... 74Figure 74: Video Calling Party Packet ETE Delay in normal traffic ............................................ 74Figure 75: Video Calling Party Packet ETE Delay in congestion traffic....................................... 75Figure 76: Video Calling Party PDV in normal traffic .................................................................. 75Figure 77: Video Calling Party PDV in congestion traffic ............................................................ 76

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Chapter 1THE PROJECT DESCRIPTION

This chapter shows the introductory part of the project. This chapter consists of theoverview of the current state of technology, project objectives, scope and limitations of theresearch, importance of the project, definition of terms, as well as the Project Methodology.

1.1 Project Description

As the business grows with complexity, the number of customers continues to grow,hence, this project aims to study how the organization, YemenNet, will deal with satisfiedcustomers and deal with highly qualified network.

Today, YemenNet is the most famous organization and administration in YemenTelecom (YT). This organization management needs to find out how it would be possible towidely use MPLS technology that offers services to customers as a part of their business concept.

MPLS network is the most important resource for increasing the economic growth inYemen. There has been much debate on whether the investment in MPLS will improveproductivity.

1.2 Overview of the Current Technology

YemenNet was created in 2001 and began operations in 2002. It specializes in themanagement of Internet services and data transmission, and offers services, such as Internetbroadband, Frame Relay, ATM, MPLS service connections like permanent virtual circuits (PVC),hosting services, and wireless internet, etc., all over the Republic of Yemen.

Frame Relay/Asynchronous Transfer Mode (FR/ATM) network has been working in2002 up to now with a total throughput (switch fabric) of 1.2Gb/s over IGX8400 Cisco Switches.

Because of the increasing demand for broadband Internet services (ADSL2+) PublicTelecommunication Corporation (PTC) in Yemen Telecom started implementing the project ofInternet Protocol/Multi-Protocol Label Switching (IP/MPLS) in 2009 with a total throughput(switch fabric) of 640Gb/s in some cities in Yemen.

1.2.1 Some definition of terms

The following terms related to the research are defined operationally for betterunderstanding:

The customer base is the group of customers who repeatedly purchase the goods orservices of a business. These customers are main sources of revenue for a company. Thecustomer base may be considered the business' target market, where customer behavior is wellunderstood through market research or past experience. Relying on a customer base can makegrowth and innovation difficult. (Customer base, Wikipedia)

Frame Relay (FR) is a standardized wide area network technology that specifies thephysical and logical link layers of digital telecommunications channels using a packet switching

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method. Network providers commonly implement Frame Relay for voice (VoFR) and data as anencapsulation technique, used between local area networks (LANs) over a wide area network(WAN). Each end-user gets a private line (or leased line) to a Frame Relay node. The FrameRelay network handles the transmission over a frequently changing path transparent to all end-user extensively used WAN protocols. (Frame Relay, Wikipedia)

Asynchronous Transfer Mode (ATM) is a telecommunications concept defined byANSI and ITU (formerly CCITT) standards for carriage of a complete range of user traffic,including voice, data, and video signals, and is designed to unify telecommunication andcomputer networks (Asynchronous Transfer Mode - Wikipedia). It uses asynchronous time-division multiplexing (TDM), and it encodes data into small, fixed-sized cells (53 Bytes). Thisdiffers from approaches such as the Internet Protocol or Ethernet that use variable sized packetsor frames. ATM provides data link layer services that run over a wide range of OSI physicalLayer links.

Multiprotocol Label Switching (MPLS) is a mechanism in high-performance (Rosen,Viswanathan, & Callon, 2001) telecommunications networks that directs data from one networknode to the next based on short path labels rather than long network addresses, avoiding complexlookups in a routing table (Multiprotocol Label Switching, Wikipedia). The labels identify virtuallinks (paths) between distant nodes rather than endpoints. MPLS can encapsulate packets ofvarious network protocols. MPLS supports a range of access technologies, including T1/E1,ATM, Frame Relay, and DSL. MPLS operates at a layer that is generally considered to liebetween traditional definitions of layer 2 (data link layer) and layer 3 (network layer), thus, isoften referred to as a "layer 2.5" protocol.

1.2.2 Problem Statement

The MPLS network has been installed and worked in 2009 with core, edge, and accessnetwork. The demands for services increase day by day and MPLS network needs greaterconcerns from YemenNet and PTC top management, to be extended and cover all areas in thecountry. The top management in PTC and some technical engineers are still thinking in legacynetworks investment and lack of a knowledge and good utilization of MPLS in YemenNet whichis less than 10 percent in core link of 10Gbps for only data and internet traffic.

Finally, the performance of MPLS technology in YemenNet would impact onproductivity and customer base by introducing the new real-time applications (VoIP and Video).The problem statement mentioned above would lead us to the attainment of the project goals.

1.3 Project Objectives

1.3.1 General Objective

The general objective of this research is to investigate how to use MPLS technology inorder to increase the customer base in YemenNet.

1.3.2 Specific Objectives

This subsection states the specific targets that must be met:

1. To identify the current services provided by YemenNet to customers.

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2. To analyze the problem of services provided by YemenNet.3. To find ways to address the problems which were identified in objective no. 2.4. To identify additional services which may be provided by using MPLS technology.5. To assess the impact of the additional services by using MPLS technology. The

additional Services are like the real-time applications (VoIP and Video) implemented byusing MPLS-TE , the quality of service (QoS) and care about customer to get a servicelevel agreement (SLA).

1.4 Scope and Limitations of the Project

1.4.1 Scope

This research would handle the technical aspects of the MPLS technology, which werethe most important issues in transmission network to carry and control all services.

This study was conducted to find out how YemenNet could use the equipment of MPLStechnology properly and efficiently to get customer satisfactions and increase customer base byintroducing the new services in real-time applications over MPLS network.

1.4.2 Limitations

The study was limited to the creation of a management system that would cater to thespecific needs of the YemenNet. The most important research and test of the MPLS Technologywould be made by using OPNET modeler to simulate three scenarios and make comparisons. Itwould be useful using some techniques and models to understand MPLS technology conceptperfectly.

Due to time constraint, this study will be applied only to internal operations ofYemenNet, not to all Yemen Telecom. It will be applied, especially in MPLS QoS, TE and FRRparts, to increase customer base by implementing new services.

1.5 Significance of the Project

Nowadays, the rapid growth in data services, market competition, and the emergence ofnew technologies, brings about evolution of the network structure. As the new technologymatures, the user needs refinement and new value-added services, such as MPLS VPN, video-on-demand (controllable multicast such as IPTV), and VoIP, QoS early pure Ethernet IP MAN/WAN.

In any network, there are three outstanding issues: the handling capacity bottleneckexists, management and operations are weak that is why it is difficult to achieve a new value-added service, and most especially without using MPLS QoS services and TE.

The project is proposed to Yemen Telecom, for the transition to an integrated informationservice provider. The telecommunications MAN/WAN ongoing optimization of transformation isin response to users demand and market competition.

The optimized MPLS will respond to the question of how to adapt to the needs of therapid growth of information technology and the rapid development of the two-storyinterconnected business telecommunications..

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This research would examine MPLS TE and QoS, on its capability to provide users witha highly reliable, highly secured enterprise Internet business and to satisfy users with SLAs. Theincreasing demand for high-speed internet access is due to the rapid growth of the Internet overthe last decade.

In addition, this research will help the top management in YemenNet how to manage andincrease the customer base by implementing new services in real-time applications.

The significance of research may be analyzed and examined entirely in the managementof YemenNet, if it is applied perfectly, it will be reflected in the customers high satisfaction bySLA.

The result of this study will provide YemenNet an open mind in accepting the challengesof todays modern technology which will help provide services efficiently, effectively, andwidely.

1.6 Project Methodology

There are many ways for the researchers to gather data for this study, which could helpthroughout the project. The primary source of data that the researcher used was data collectionfrom YemenNet and from websites.

Books, journals, reports, undergraduate thesis, published and unpublished materials, andother documents are the secondary resources for the project as well as ample forms. All materialsmentioned above had been obtained through Internet websites.

1.6.1 Theoretical framework

The research methodology presented in this project is based on Qualitative approach. Inthis Qualitative approach, four steps are considered, viz:

Evaluate the performance of MPLS network in terms of QoS and TE. Evaluate the MPLS resiliency by using Fast Reroute (FRR) technique. Use some frameworks of OPNET Modeler 14.5 to get the real results in comparison

between legacy network (IP) and MPLS network. Simulate some new services in real-time applications, like VoIP and Video Conference in

both networks.

1.6.2 Data gathering

Data Collection is an important aspect of any type of research study. Inaccurate datacollection can impact the results of a study and ultimately lead to invalid results. The purpose ofdata collection is to obtain information to keep on record, to make decisions about importantissues, to pass information on to others.

The researcher has worked more than 13 years in YemenNet, made a lot of trainingcourses for the new engineers, and has acquired experience in transmission system devices. AfterDirector General of PTC has approved the request to use the resources of YemenNet, theresearcher collected all needed information that would help to address the project objectives inchapter 4.

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1.6.3 Data analysis

Data can be analyzed with the help of an appropriate computer program. In this research,some appropriate programs will be used to perform this project, such as:

The OPNET Modeler 14.5 is well-known for network simulated, design and attractivefeatures. In the OPNET simulator, different network entities are needed to configureaccurately support selective application services of the network.

Visio program was used for drawing network topology. Microsoft Word 2007 was to write this project and used its References to collect all

resources in APA style.

1.6.4 Schedule of activities

This research consists of seven chapters, as mentioned in Table 1 that would describe theactivities, names, and the period over eight months, from July 2013 to February 2014 after thepanelists from Taiz and Delft Universities have accepted this project proposal in May 2013.

Table 1: The Schedule of the Project ActivitiesTime &Activity

Jul2013

Aug2013

Sept2013

Oct2013

Nov2013

Dec2013

Jan2014

Feb2014

Writing ProjectIntroduction in CH1Writing LiteratureRelated in CH2Writing Frameworksof Project in CH3Collect Data aboutthe Existing Systemin CH4Writing TheProposed Solutionby OPNET in CH5Writing ResultsExplanations in CH6Writing The FutureWork in CH7 andReview ALLChapters

According to table 1, the researcher took a long time understanding the concept ofOPNET Modeler 14.5 due to the lack of training and resources. Help icon and documentationpackage in software helped the researcher to understand how it works, and helped this project tomake a good decision of investing in MPLS technology.

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Chapter 2REVIEW OF RELATED LITERATURE

This chapter presents the review of literature and studies relevant to the present researchwhich were culled from the internet and published/unpublished materials. This chapter wasdivided into three parts: related literature, theoretical related studies, and practical related studieswhich were simulated by using OPNET.

2.1 Related Literature

According to Publication Manual of the American Psychological Association (2010),Literature reviews, including research syntheses and meta-analyses, are critical evaluations ofmaterials that have already been published. In this manner the researcher would mention thebooks which gave a perfect concept to this project.

Evans, J., & Filsfils, C. (2007), authors of the book Deploying IP and MPLS QoS forMultiservice Networks Theory and Practice, gave complete information about QOSRequirements and Service Level Agreements, Introduction to QOS Mechanics and Architectures,Deploying Diffserv and Core Capacity Planning and Traffic Engineering. This book helped theresearcher to use some frameworks in QoS and TE with VoIP.

Minoli, D. (2002), author of the book Voice over MPLS Planning and DesigningNetworks explained Motivations, Developments, and Opportunities in Voice over Packet (VoP)Technologies, Technologies for Packet-Based Voice Applications, Quality of Service (QoS),Motivations, Drivers and Approaches, and Advantages of VoMPLS. This reference gave astandard frameworks and information in MPLS and VoIP that would be useful in this project inthe succeeding chapters.

Reagan, J. (2002), in his book, CCIP MPLS Study Guide covered everything that needsto pass the CCIP MPLS exam. This book did not cover everything there was to know aboutMPLS and MPLS VPNs, only those necessary to successfully pass the exam. The materialcovered in this book serves as a foundation for your later studies in MPLS. This book taught howto configure and maintain Cisco routers in a large internetwork. Each chapter begins with a list ofthe topics covered that relate to the CCIP MPLS test, to make sure to read them over beforeworking through the chapter. Finally, this book helped the researcher to understand using MPLStechnology in practical way and use some terminology definitions.

Ghein, L., (2007), author of the book MPLS Fundamentals discussed everything aboutMPLS Fundamentals. This book, helped the researcher to use the resources of MPLS in writingsome chapters of the research.

Besides, books, articles and researches, references from RFCs website were also utilized,as shown in Table 2: Reference Documents . These RFCs provided definitions of MPLStechnology that were written in this project.

Table 2: Reference Documents (MPLS Model /Release 14.5 Description. OPNETDocumentation., 2008)

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Model Features DocumentMPLS TE RFC-2702Requirements for Traffic Engineering

Over MPLSDifferential Services (DiffServ) DiffServ extensions, as defined in RFC-2475

FECs RFC-3031Multiprotocol Label SwitchingArchitecture

IGP shortcuts draft-hsmit-mpls-igp-spf-00

Dynamic LSPs StaticLSPs

RFC-3031Multiprotocol Label SwitchingArchitecture

OSPFTEIS-IS TE

RFC-2676QoS Routing and OSPF Extensions

LDP RFC-3036LDP Specification

CR-LDP RFC-3212Constraint-based LSP Setup Using LDPRSVP-TE RFC-3209RSVP-TE: Extensions to RSVP for LSP

TunnelsA framework for layer-3 PP VPNs RFC-2547BGP/MPLS VPNs

BGP/MPLS VPNs draft-ietf-ppvpn-framework-05

QOS Architecture RFC-2475An Architecture for DifferentiatedServices

Assured Forwarding PHB Group RFC 2597

An Expedited Forwarding PHB RFC 2598

MPLS Support of DifferentiatedServices

RFC-3270Multi Protocol Label Switchingdraft-ietf-mpls-diff-ext-08

Fast reroute with bypass tunnelsLSP protection with ingress backup

draft-ietf-mpls-rsvp-lsp-fastreroute-00

Lu, Z., & Yang, H. (2012), stated in the book, Unlocking the Power of OPNETModeler, some facts about Introduction to OPNET, Installation of OPNET Modeler and settingup environments, OPNET Modeler user interface, Debugging simulation, OPNET programmingin C++ and Traffic in OPNET simulation.

According to (Lu & Yang, 2012, p. 5) OPNET Modeler is the foremost commercialproduct that provides network modeling and simulation software solution among the OPNETproduct family. It is used widely by researchers, engineers, university students, and the USmilitary. OPNET Modeler is a dynamic discrete event simulator with a user-friendly graphic userinterface (GUI), supported by object-oriented and hierarchical modeling, debugging, and analysis.OPNET Modeler is a discrete event simulator that has evolved to support hybrid simulation,analytical simulation, and 32-bit and 64-bit fully parallel simulation, as well as providing manyother features. It has grid computing support for distributed simulation. Its System in- the-Loop

8 8

interface allows simulation with live systems which feed real-world data and information into thesimulation environment.

Aboelela, E. (2003), author of the book Network Simulation Experiments Manual (TheMorgan Kaufmann Series in Computer Networks) explained 13 practical labs simulated byOPNET IT Guru Academic Edition.

All methods of these labs provided the step by step procedure, and explained to first timeusers how to use OPNET.

The researcher also used OPNET Modeler 14.5 as reference for tutorial.

Researchers use the term information technology or IT to refer to an entire industry. Inactuality, information technology is the use of computers and software to manage information. Inthis project, MPLS Technology is referred to as Information Technology (or IT) because any newprotocol in Telecom becomes an IT. IT has become responsible in storing, protecting, processinginformation and as well as transmitting the information then later retrieving it over MPLSnetwork.

In todays business environment, organizations are trying to reduce and eradicate humaneffort but increasing productivity. Therefore, MPLS technology is the best solution in increasingcustomer base with high bandwidth and low cost to satisfy the customer's satisfactions. The studyof increasing customer base in YemenNet by using MPLS technology will be helpful and usefulto solve all project objectives.

2.2 Theoretical Related Studies

The following are some of the theoretical studies that were considered relevant to thepresent project:

Sabri, G. (2009), at Blekinge Institute of Technology, entitled QoS in MPLS and IPNetworks," provides broader information about IP and MPLS technologies and routing protocols.Internet architecture and problems in an IP networks are illustrated when different internetprotocols are used. Small focus is provided on the demand-oriented real time applications anddata traffic for QoS parameters in IP and MPLS networks. Evaluation of QoS guaranteeparameters such as delay, jitter and throughput are described with state of art study results mainlyfor real time applications in IP and MPLS networks.

This paper (Sabri, 2009, p. 87) concluded that IP technology is however not capablehandling high data rate stream of voice and video data as compared to simple datagram. Toincrease data transmission rate at the core network either increase the bandwidth orimplementing new protocol is required. However, increasing bandwidth through physical meanis unnecessary because in an internet data transmission traffic follow through certain routingprocedure to deduce routes from source to destination in connection oriented or connectionlesstransmission mechanism. The routes deduce through IP routing protocol follow the shortest pathroutes or least cast routes which leads to the circumstances of network congestion, underutilizednetwork resources/links and proper load balancing procedures at the network level.

To overcome the problems associated in IP network, MPLS networks are introducedbecause they use label switching technology at the IP core routers to make routing mechanism

9efficient, configure data packet with small labels at the start and the end of the MPLS doto deliver QoS guarantee transmission almost any voice and video application. Mforwarded equivalency class parameters differentiate incoming traffic classes and laccording to diffident priority based on MPLS traffic engineering implementation. Moffers various routing protocols to define routs at each MPLS domain and outside MPLand performs connectivity operation through BGP and EGP. A part from QoS guarantetime applications, traffic engineering provide better utilization of network recoursedevices /link are underutilized and limits/avoid congestion. MPLS also offimplementation and interconnected with other network to provide secure andcommunication.

Finally, this study would help the proponent to immigrate from the legacy(TDM) which is still used in Internet network (ADSL Access Network in YemenNet)backbone over MPLS network.

Ikram, I. (2009) at Blekinge Institute of Technology, entitled Traffic EngineeMPLS and QoS," summarizes MPLS concept. MPLS traffic engineering is proposetaking advantage of MPLS, traffic engineering can route the packets through explicioptimize network resource utilization and traffic performance. MPLS provides a robustservice control feature in the internet. MPLS class of service feature can work in accordother quality of service architectures for IP networks.

In this thesis report, Ikram (2009, p. 92) focused in MPLS network. MPLSQOS, and issue of MPLS, tried to provide a meaningful thought regarding the topic. MQOS provide efficient transmission, reliability scalability, fault tolerance, load distribuprotection, end-to-end connectivity, and marvelous achievement that provide connectiotechniques with integration of IP networks. Point-to-multipoint (P2MP) supportincorporated in the inventive MPLS provision. Users wishing to transmit IP multictraversing an MPLS network were mandatory to set up point-to-point (P2P) LSPs stsource point of the multicast traffic MPLS PE to each intended exit point (destination) MMPLS from a theoretical approach of TE and its component like LSR, LER, LSP,RSVP, RSVP-TE, labels the necessities of the advantage of traffic engineeringimplementation with MPLS. General and some practical scenarios was analyzed, anstudy of MPLS with TE is carried out. To enhance the performance of networksunderstanding of how traffic is mapped into any particular LSP is also discussed.

In fact, this study was very useful to summarize MPLS technology and prMPLS utilize network resource more efficiently to minimize the congestion with a reobjective function for TE. It brings revolution and facilitates several services such asapplications support in network.

The thesis of Fjellskl, E., & Solberg, S. (2002) at Agder University CollegEvaluation of Voice over MPLS (VoMPLS) compared to Voice over IP (VoIP)conclusion that VoMPLS is a better solution than VoIP.

It is natural to have VoMPLS as an option when implementing MPLS in aWhether it will be used in the network as the main carrier of voice depends on differelike voice quality (compared to other Voice over Packet [VoIP] solutions), implementatrevenues, demands (from customers), and the network providers need for implementatio

When a service like VoMPLS is introduced, one has to turn the attention tohigh-capacity scalable services. Some success criteria may be (Fjellskl & Solberg, 20029

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Easy and cost-effective scale to meet customer demand. Offer the QoS requested and give such guarantees. Ensure compatibility with existing network infrastructure and protocols to enable a

smooth transition and reduce the cost. Transition existing customers to a new service. Deliver telephony services with the

same or, more desirable, better level of quality than earlier.

If VoIP uses Header Compression (HC) and the layer 2 protocol is MPLS, the differencesin overhead size are minor compared to VoMPLS (layer 2). If there are minor or no differences invoice quality in the two scenarios, the need for VoMPLS may be redundant.

MPLS-TE brings a unique QoS solution to MPLS based networks. The purpose ofMPLS-TE is to help give voice data, traveling over the MPLS traffic engineered network, betterQoS guarantees.

Finally, this paper gave the evaluation of VoMPLS which was performed only throughtheoretical studies and gave a researcher a good chance to make a comparison between VoMPLSand VoIP by using software simulator.

2.3 Practical Related Studies

The following were some of the practical studies that were done by using OPNET andgave numerical results and charts which were being relevant to the present project:

The following are some of the practical studies that were done by using OPNET and gavenumerical results and charts which were being relevant to the present project:

The study of Jannu, K., & Deekonda, R. (2010) at Blekinge Institute of Technologyentitled, OPNET simulation of voice over MPLS with considering Traffic Engineering, was touse voice packet end-to-end delay performance metric. An approach is made to estimate theminimum number of VoIP calls that can be maintained in MPLS and conventional IP networkswith acceptable quality, and to help the network operators or designers to determine the numberof VoIP calls that can be maintained for a given network by imitating the real network on theOPNET simulator. This study proved that MPLS provides the best solution in implementing theVoIP application (Internet Telephony) compared to conventional IP networks and (Jannu &Deekonda, 2010, p. 30) gave a good conclusion about MPLS, viz:

Routers in MPLS takes less processing time in forwarding the packets, this is moresuitable for the applications like VoIP which posses less tolerant to the networkdelays.

Implementing of MPLS with TE minimizes the congestion in the network. TE inMPLS is implemented by using the signaling protocols such as CR-LDP and RSVP.

MPLS suffers minimum delay and provides high throughput compared toconventional IP networks.

Finally, this thesis helped the researcher to know how to use the OPNET simulation totest some features of MPLS like QoS, TE, and FRR, and gave some steps in OPNET.

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Salah, K., & Alkhoraidly, A. (2006) in an article presented in the International Journal ofNetwork Management, entitled, An OPNET-based simulation approach for deploying VoIP,gave a conclusion about VoIP applications. It is required that end-to-end packet delayshould not exceed 150 ms to make sure that the quality of the established VoIP call isacceptable .

They found (Salah & Alkhoraidly, 2006, p. 163) the packet delay could be divided intothree contributing components, as identified below:

Encoding, compression, and packetization delay occurs at the sender. In the G.711 codecthe delay introduced for encoding and packetization are 1 ms and 20 ms, respectively.The delay at the sender, considering above two delays along with compression, isapproximated to a fixed delay of 25ms.

Buffering, decompression, depackatization, and playback, delay result in the receiver.The total delay due to these factors is approximated to a fixed delay of 45ms.

The delay, considering from sender and receiver, can calculate the network delay whichshould not exceed 80ms or (150-25-45). This delay actually is the sum of the delaysgiven from propagation, transmission and queuing delay in the network.

It means that the network delay from the source to receiver shouldnt exceed 80 ms inorder to provide acceptable quality for established VoIP call.

Finally, this study gives a standard value for accepting VoIP in OPNET simulator and inreal network shouldnt exceed 80ms.

Almofary, N.,H., Moustafa, H.,S., & Zaki, F.,W. (2012) from International Journal ofModern Computer Science & Engineering Entitled Optimizing QoS for Voice and Video UsingDiffServ-MPLS gave the comprehensive study showed general improvement in the throughput,jitter and delay particularly of voice and video transmission when using DiffServ-aware MPLSnetwork as compared to pure IP only or MPLS only.

The simulation results in (Almofary, Moustafa, & Zaki, 2012, p. 31) showed that theperformances of traffic engineering parameters in MPLS network is much better as compared totraditional IP networks. Also MPLS support of DiffServ satisfies both necessary conditions forQoS: guaranteed bandwidth and differentiated queue servicing treatment. MPLS satisfies the firstcondition, i.e., it forces applications flows into the paths with guaranteed bandwidth; and alongthese paths, DiffServ satisfies the second condition by providing differentiated queue servicing.

This report gave idea to make a comparison by using MPLS only and MPLS withDiffServ by OPNET after giving a positive impact in MPLS rather than IP.

Khan, A. S., & Afzal, B. (2011) at Halmstad University entitled MPLS VPNs withDiffServ A QoS Performance study" which was to investigate QoS parameters (e.g. delay, jitterand packet loss) over MPLS VPNs environment. It will help the service providers and enterprisenetwork customers to maintain QoS for voice, video and data traffic over MPLS VPNsenvironment.

From (Khan & Afzal, 2011, p. 44) MPLS combined the features of Private WANconnectivity (Frame Relay, ATM, and Leased Lines) and layer2 VPNs.

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MPLS VPN reduced the complexity of network operations. It also reduced the cost tomanage the network operations. By using DiffServ QoS model it was easy to manage networkresources and getting the maximum utilization from available resources. Enterprise networks sendall video, audio traffic as well as elastic data traffic over the same network infrastructure. We canuse DiffServ QoS model to gain the quality of experience for end user in MPLS VPNenvironment. It is necessary for the customers network and service providers network to bettermanage the resources. DiffServ QoS model itself does not create bandwidth but it manages theavailable bandwidth. It is used for well-defined capacity planning and overall applicationgovernance process. Network engineers can make traffic management decisions by analyzingnetwork capacity and applications requirement of resources.

MPLS is a fast packet switching technology and reduces the end-to-end delay.TheDiffServ QoS model is more effective and scalable than the IntServ QoS model. The betterresults could be gotten in MPLS VPN network environment by using a DiffServ QoS model.Without DiffServ QoS model in MPLS VPN network environment delay, jitter, and packet lossare rising with the increase of traffic on the network. With the configuration of DiffServ QoSmodel, it provides almost constant delay, jitter, and packet loss in all different traffic loadsbounded by the limitations. Limitations are considered by the means of allocated resources forspecific traffic class. Scalable video and audio service with good quality, over the enterprisenetwork using MPLS VPNs together with DiffServ QoS model, can be provided.

Results were taken from the tests using NQR. In MPLS VPN, environment delay wascalculated between 0.290ms to 2.079ms, jitter was 0.060ms to 1.753ms, and packet loss was0% to 20.9839%. After using the DiffServ QoS model, delay was calculated between0.649ms to 0.662ms, jitter was between 0.056ms to 0.061ms, and packet loss was 0%.

Finally, this report offered a fact, that without using DiffServ QoS model delay, jitter andpacket loss are increasing as the traffic increases on the network. With a DiffServ enablednetwork, the increase of traffic over network will not affect delay, jitter and packet loss andprovide constant level of service quality. Also, it would prove that MPLS network should beinstalled over all country because of the highest performance of it and the best managementnetwork.

The study of Adhikari, D., & Kharel, J. (2011) at Blekinge Institute of Technologyentitled Performance Evaluation of Voice Traffic over MPLS Network with TE and QoSImplementation the performance variation seen in the network after, and before implementationof QoS in the MPLS-TE network were analyzed. Different scheduling algorithms were used inthe process of implementing QoS to check if they have any effect in the performance of thenetwork for voice.

After the analysis of the result from the simulation (Adhikari & Kharel, 2011, p. 32), itwas concluded that the use QoS in MPLS-TE network performs better than normal MPLS-TEnetwork for voice packets as it provided lower delay and lower jitter. In the second phase,different basic scheduling algorithms used for DiffServ architecture in process of QoSimplementation, among the three algorithms are FIFO, PQ and WFQ.

Finally, this thesis gave a good framework for using different algorithms and QoScombined with TE which summarized by giving the following:

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Described the QoS parameters for real time data traffic like voice and video as delay,jitter, and packet loss rate.

The performance of MPLS-TE network had increased after QoS implementation andreduced the delay and jitter.

PQ algorithm performed better than basic FIFO and WFQ providing lower jitter,lower end-to-end delay and minimum packet delay variation (PDV).

Bongale, M.,B., & Nithin, N. (2012) from International Journal of ComputerApplications Analysis of Link Utilization in MPLS Enabled Network using OPNET IT Guruexplained poor link utilization in RIP and OSPF networks. It is seen that networks configuredwith RIP and OSPF routing techniques are not capable of handling the incoming trafficefficiently. When the network traffic increases, shortest path from source node to destinationnode is heavily congested and lead to loss of transmission data.

In this paper of Bongale & Nithin (2012, p. 39) it was successfully shown and simulatedthat MPLS was capable of handling incoming traffic efficiently by distributing the traffic overunutilized links. This would ensure packets entering into MPLS core reach the destination withminimum queuing delay. MPLS-TE is most suitable for huge traffic volume.

Finally, this paper gave another support for using OPNET in the preformed simulations,it had considered aggregate data consisting of web browsing and voice traffic only.

AlQahtani, S. M. (2010) in a research at King Saud University, entitled QoSComparisons for MPLS and MPLS/DiffServ networks," introduced the design andimplementation of MPLS and MPLS / DiffServ Network under the OPNET simulationenvironment.

In (AlQahtani, 2010, p. 77) the QoS parameter analysis, it was evident that theMPLS/DiffServ network is much superior in handling QoS as its architecture provides morequeues for different classifications of traffic that allows better commitment to SLAs forcustomers.

It was shown that MPLS/DiffServ provided faster traffic delivery than MPLS, the Datatraffic (FTP) response time of MPLS/DiffServ was lower than the response time of MPLS, and itwas much lower in the case of heavy load. The delay for both voice and video show, thatMPLS/DiffServ had lower delay than MPLS in the case of light and heavy load, with thedifference having a larger value in the case of heavy load. The delay variation of voice and videoin case of MPLS/DiffServ were lower than the delay variation MPLS in the case of light andheavy load, with the difference having a larger value in the case of heavy load.

The results for Packet Dropping analysis clearly showed that MPLS has a higher packetdrop than MPLS/DiffServ in both Voice and Video traffic. The data packet dropped inMPLS/DiffServ is similar to the voice and video traffics, in the case of light load. In the case ofheavy load, the data packet drop of MPLS/DiffServ is higher than in MPLS due to the lowestpriority assigned to the data traffic in DiffServ class definition as compared to the video traffic,while the voice traffic is negligible due to its small size.

It was looked at the performance of Voice and Video using four different queuing policesfor MPLS/DiffServ, i.e., DWRR, MDRR, PQ and WFQ. From the graphs, it was shown thatWFQ gave the best result for voice for both delay and delay variation, while PQ gave the best

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result for video for both delay and delay variation. MPLS had higher delay than theMPLS/DiffServ for all queuing policies. The delay of video was very small and was almost thesame for all queuing polices.

From the results, we could find out that WFQ gave the best performance, lowest delay forboth data and voice.

It was found, the delay variation and end-to-end delay for Voice and Video traffic, pageresponse time for HTTP traffic (Data), and throughput and utilization for each traffic type usingWFQ. Each parameter was measured against network load. For delay variation it was seen that inMPLS and MPLS/DiffServ the performance was almost the same for light load (below 40%) forboth voice and video traffics. For heavy load (over 70%) MPLS delay variation was much highercompared to MPLS/DiffServ delay variation for both traffics.

Furthermore, it was seen that packet end-to-end delay for MPLS and MPLS/DiffServ wasthe same for light load (below 40%) for both voice and video traffics. For heavy load MPLSdelay was slightly higher compared to MPLS/DiffServ delay for voice traffics. In MPLS/DiffServvoice had higher priority than data while in MPLS it was the same, and the data traffic was muchhigher than voice traffic hence the delay in the case of MPLS would be higher than the case ofMPLS/DiffServ. For video traffic MPLS delay was much higher compared to MPLS/DiffServdelay, which is the expected desired result since video was given the highest priority.

It was shown that throughput for data was slightly better for MPLS as compared toMPLS/DiffServ, due to the bursty nature of data traffic and noting that data burst happen in shorttimes. Voice had lower priority than video, hence video packets were sent more than voicepackets, and hence lower throughput was seen for voice for MPLS/DiffServ. Voice is not asbursty as data, so there was a distinct difference between MPLS and MPLS/DiffServ. In the caseof MPLS, video had the same priority as others but it size was 90% of total traffic hence it wasoccupying 90% of the queue size, that equals to 90 packets, while in the MPLS/DiffServ it wasassigned a queue of size 33 packet hence it had higher packet drop. In this case, less packetssucceeded in going out hence the throughput was seen to be lower.

Also, it was shown that the page response time for MPLS/DiffServ was lower thanMPLS, this can be explained by the fact that in MPLS/DiffServ, a dedicated buffer space isassigned for data. Even if the priority of data queue is lower than that of the video queue, but thisis overcome by the lower percentage of data traffic in MPLS.

At high load the MPLS/DiffServ had lower packet drop than MPLS, this can beexplained by the fact that the major traffic is video, and in addition the video traffic was given adedicated space and higher priority than other traffics, therefore the video traffic would utilizeMPLS/DiffServ network much better than MPLS network which would lead to lower packetdropping.

Besides, it was shown that the failure and recovery mechanism of MPLS/DiffServnetwork. The resilience of the network shows that it can support network failures and recoverfrom them efficiently.

Finally, this thesis compared the performance of MPLS network and MPLS/DiffServnetwork using different scenarios and measuring different QoS parameters (Delay variation,delay, page response time, throughput, utilization, and packet drop). In all these sections and

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almost for all the measured QoS parameters, the performance of MPLS/DiffServ network wasbetter than MPLS network. This thesis gave a good road map for the researcher to use OPNETand applied the network design with the existing network in YemenNet as it was shown inchapter 5.

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Chapter 3THEORETICAL FRAMEWORK

This chapter presents a brief overview of MPLS technology and its importance to theemerging multi-service internet. MPLS concepts, such as labels, switching label stacking, labeldistribution method and traffic engineering, label switched paths (LSPs), Forward EquivalenceClasses (FECs), and label merging were discussed in detail. Resource Reservation Protocol alongwith label distribution protocol were also discussed. Additionally, MPLS applications would bementioned in brief.

Furthermore, this chapter also provides a brief discussion on OPNET Modeler Simulatorwhich was used to test a network design, created a simulated network, and run it through real-world scenarios, to see how it could thrive with different technologies and network conditions.

3.1 MPLS Introduction

Multiprotocol label switching (MPLS) is a versatile solution to address the problemsfaced by present-day networks speed, scalability, quality-of-service (QoS) management, andtraffic engineering (Trillium, p. 1). MPLS has emerged as an elegant solution to meet thebandwidth-management and service requirements for next-generation Internet protocol (IP)based backbone networks. MPLS addresses issues related to scalability and routing (based onQoS and service quality metrics) and can exist over existing asynchronous transfer mode(ATM) and frame-relay networks.

To honor the service level guarantees, the service providers not only have to providelarge data pipes, but also look for architectures which can provide & guarantee QoS (Quality ofService) guarantees and optimal performance with minimal increase in the cost of networkresources.

MPLS is standardized by the IETF (Internet Engineering Task Force) in RFC 3031(Rosen, Viswanathan, & Callon, 2001).

3.1.1 Why do network providers motivate for MPLS?

Demand for QoS services with only software upgrade. Demand for ATM-like classes of services without the cost of ATM. Growing number of users. Increasing need for bandwidth. Diverse service types and QoS requirements. Managing bandwidth versus buying bandwidth. Limitations of existing core technologies. Movement to a single unified network.

3.1.2 MPLS Combines Routing and Switching

As shown in Figure 1, the main concept of MPLS which combines IP routing and ATMswitch IP routing is pure Layer 3 technology which provides rich functionality: wide range ofprotocols, interface types, and speeds.

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ATM switching is pure Layer 2 technology which does simple forwarding of Layer 2protocol packets based on circuit numbers. One view is that MPLS combines the best of bothATM and IP which rich functionality and flexibility of Layer 3 routing and Speed and simplicityof Layer 2 switching. So MPLS is Layer 2.5 protocol.

Figure 1: MPLS Combines Routing and Switching (OPNET Technologies, Session 1801Introduction to MPLS Technology Tutorials, 2004, p. 8)

3.1.3 MPLS Header and Label

MPLS Header is 32 bit in length. That 32 bits Header field is embedded between layer 2and layer 3 headers. Shim header encapsulates every incoming packet. They are shimmedbecause they are placed between the existing headers. As it is a small header so it is appropriateto call it shim. Figure 2 shows MPLS header format.

Figure 2: MPLS Shim Header (Davie & Farrel, 2008)

MPLS label contains the following information as it is shown in Table 3.

20 bit contain label 3 bit contain exp 1 bit contain in S 8 bit contain in TTL

Table 3: MPLS Label Format (Rosen, et al., 2001)0 1 2 3

0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4567 8 9 0 1

Label Exp S TTL

Table 4: MPLS Labels between Layer-2 and Layer-3 HeadersL2 Header Last Label . First Label L3 Header

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The shim header may contain more than one label as shown in Table 4. Labels act as pathidentifiers, at each router the contents of the labels are examined and the next hop is determined.The fixed length 20 bit space in the label is set aside for the address space having a localsignificance only. Labels are chosen locally and are advertised by a router to its neighbors using aLabel Distribution Protocols (LDP) and are swapped away of each incoming packet before beingforwarded to the next routers. MPLS is a datagram oriented technology though it uses IP routingprotocols. In MPLS label the EXP is a 3 bit field set aside for experimental use. S bit is a 1 bitfield that indicates the bottom and is set for the stacking of labels and finally TTL is an 8 bit fieldwhich determines the time and number of hops a packet has to traverse before it can die.

3.1.4 Label Space

Label space means the range of label values, and the label space is classified (HuaweiTechnologies Co., 2013) as follows:

015: indicates special labels. 161023: indicates the label space shared by static LSPs and CR-LSPs. 1024 or above: indicates the label space for dynamic signalling protocols, such as LDP,

RSVP-TE, and MP-BGP.

3.1.5 Forward Equivalence Class (FEC)

Each label has a local significance and short identifier with fixed length, which is used toidentify a particular Forward Equivalence Class (FEC). When they reach at MPLS network at theingress node, packets are divided into different FECs, on which different labels are encapsulatedas it is shown in Figure 3.

Figure 3: Forward Equivalence Class (FEC)(OPNET Technologies, Session 1801 Introduction toMPLS Technology Tutorials, 2004, p. 16)

Forward Equivalence Class (FEC) set of packets where they have related characteristicswhich are forwarded with the same priority to the same path. This set of packets is has the sameMPLS label. Each packet in MPLS network is assigned with FEC only once at the Ingress router.

Packets are classified into FECs, only once at the ingress to the MPLS domain. A FECidentifies a set of IP packets to map to an LSP (Label Switch Path). Packets in the same FEC,receive the same label from the ingress LSR (Label Switch Router) and are mapped to the sameLSP and forwarded over the same path (or sets of paths in the case of multi-path routing).

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The next hop label forwarding entry (NHLFE) can guide the MPLS packetforwarding. Its main contents:

Next hop address Outgoing Label Outgoing Interface information Operation to be performed on the label

FTN is short for FEC-to-NHLFE. The FTN indicates the mapping between an FEC anda set of NHLFEs. Details about the FTN can be obtained by searching the token values that arenot 0x0 in the FIB. The FTN exists only on the ingress. Hash Table hashed on the FEC name asshown in Figure 4.

Figure 4: FTN (OPNET Technologies, Session 1801 Introduction to MPLS Technology Tutorials,2004)

The incoming label map (ILM) indicates the mapping between an incoming label and aset of NHLFEs. The ILM can bind the label to the NHLFE, forming the mapping between thelabel and the NHLFE. The function of an ILM table is similar to that of the FIB that is searchedwith destination IP addresses. Thus, you can obtain all labels forwarding information in an ILMtable. Array of NHLFEs indexed on the incoming label value as shown in Figure 5.

Figure 5: ILM (OPNET Technologies, Session 1801 Introduction to MPLS Technology Tutorials,2004)

Label Information Base (LIB) can be global as one for whole node and the interface-specific is one for each interface on node. LIB contains NHLFEs. NHLFE is used to determineNext Hop, New Label, Label Operation and Outgoing interface. NHLFEs are stored in Ingressnode where FTN (FEC to NHLFE) hash table, hashed on FEC name and At Core node whereILM array, indexed on incoming label.

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3.1.6 MPLS Domain

MPLS is a technology that forward packets as a way of communication by using labels tomake forwarding decisions. MPLS forward packets by using label lookup because it is extremelyfast and efficient. As the packet enters the MPLS domain layer 3 analyses is performed and aparticular label is assigned to each incoming packet based on the layer 3 destination address.

A MPLS network consists of a number of nodes called Label Switched Router (LSRs),others nodes that connects with IP routers or ATM switches are called Label Edge Router(LERs). This router within MPLS domain that connects with the customer side, thorough which apacket enters the network with push label is called Ingress LER router as shown in Figure 6 andthe one through which the packets leaves the MPLS domain is called egress LER router withremoving label (POP label) as shown in Figure 7. The label defines the fast and effective labelswitch path (LSP) to direct the traffic all the way to the destination as shown in Figure 9.

Multiprotocol Label Switching (MPLS) is a tunneling technology used in many serviceprovider networks, MPLS domain has two main types of switches: MPLS core switch whichconsists of Label Switch Routers (LSRs) and the other is MPLS edge which consists of LabelEdge Routers (LERs), the main components of MPLS technology are explained as follows:

Figure 6: Ingress LER (OPNET Technologies, Session 1801 Introduction to MPLS TechnologyTutorials, 2004)

Label Edge Router (LER) handles L3 lookups and is component that is responsible foradding or removing the labels from the packets when they enter or leave the MPLS domain.Whenever a packet is entering or leaving MPLS domain it has to pass through LER router, whena packet enters into MPLS domain through LER which is called Ingress router, or when apacket leaves the MPLS domain through LER which is called Egress router.

Ingress LER (also called head end) does the following: Examines IP packets as theyenter the MPLS domain, Aggregates flows into FECs, Generates the MPLS header and assigns,or pushes, the initial label onto packet and Upstream from all other LSRs in the LSP.

Egress LER (also called tail end) does the following: Removes, or pops, the MPLSheader (unless using Penultimate Hop Popping), Examines the packet to determine forwarding(normal IP forward, label swap, etc.) and Downstream from all other LSRs in the LSP.

Label Switch Router (LSR) A router which is located in the MPLS domain andforwards the packets based on label switching is called LSR and usually this type is located theprovider cloud; as soon as LSR receives a packet it checks the look-up table and determines thenext hop, then before forwarding the packet to next hop it removes the old label from the header

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and attaches new label.

Figure 7: Egress LER (OPNET Technologies, Session 1801 Introduction to MPLS TechnologyTutorials, 2004)

LSR forwards traffic using label swapping by pushing and popping labels (Swap Labelsas shown in Figure 8). LSR can label swap from any input port to any output port. LSR can be arouter or switch (and label switching can be done in hardware or software) and runs one or moreIP routing protocols and uses LDP to distribute FEC/label bindings.

Figure 8: Label Switch Router (LSR)(OPNET Technologies, Session 1801 Introduction to MPLSTechnology Tutorials, 2004)

Label Switch Path (LSP) is the path set by signaling protocols in MPLS domain. InMPLS domain there are number of LSPs that are originated at Ingress router and traverses one ormore core LSRs and terminates at Egress router as shown in Figure 9.

A sequence of LSRs, from ingress to egress of the MPLS domain, that describes the pathfollowed by labeled packets in the same FEC. A unidirectional tunnel through the MPLSdomain and for a round trip, two LSPs are required. LSP May deviate from the IGP shortest pathdue to resource subscription and due to explicit routing.

Penultimate Hop Popping (PHP)

In fact, the label is useless at the last hop of an MPLS domain. In this case, the feature ofpenultimate hop popping (PHP) is applied. On the penultimate node, the label is popped out ofthe packet to reduce the size of the packet that is forwarded to the last hop. Then, the last hopdirectly forwards the IP packet or the VPN packet.

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Figure 9: Label Switch Path (LSP)(OPNET Technologies, Session 1801 Introduction to MPLSTechnology Tutorials, 2004)

Label Stack

A label stack is a set of arranged labels. An MPLS packet carries multiple labels at thesame time. The label next to the Layer 2 header is called the top label or the outer label. The labelnext to the Layer 3 header is called the bottom label or inner label. Theoretically, MPLS labelscan be nested limitlessly as shown in Figure 10.

Label-----------------------Stack

Link layerheader

Outerlabel

Innerlabel

Layer 3header

Layer 3payload

Figure 10: Label stack

The label stack organizes labels according to the rule of Last-In, First-Out and processeslabels from the top of the stack. This is Useful for IP/MPLS VPNs and TE.

3.1.7 MPLS Architecture

The MPLS architecture consists of a control plane and a data (forwarding) plane.

The control plane is connectionless and mainly responsible for distributing labels,creating the label forwarding table, and creating or deleting LSPs and summarized as follows:

Determines routes for LSPs: IGP routes or CSPF routes like OSPF-TE Signals the LSP: using RSVP-TE or CR-LDP Builds tables for label switching: FTN at ingress and ILM in the core

The forwarding plane, also known as the data plane, is connection-oriented. It can applyservices and protocols of ATM, Frame Relay, and Ethernet networks. The forwarding plane ismainly responsible for adding labels to and deleting labels from IP packets. Simultaneously, itforwards received packets according to the label and forwarding table using LFIB managed bythe control plane. See Figure 11.

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Figure 11: Architecture of MPLS(Imran, 2009, p. 23)

3.2 MPLS Application

There are three main areas of significant MPLS:1. QOS.2. Traffic Engineering (TE).3. Virtual Private Networks (VPNs) (out of the scope of this project).

As it is shown in Figure 12, it is summarized the MPLS Application and their Interaction.

Figure 12: MPLS Application and their Interaction (Imran, 2009, p. 31)

3.2.1 QOS

Highly generating revenue application are VPNs and audio/video conferencing thatrequire a significant amount of QOS support (Imran, 2009, p. 16). This is to make sure the

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availability of certain amount of bandwidth for particular applications and a guarantee for servicelevel agreement. Whereas the conventional IP network fails to do so and is unable to provide anadequate level of QOS to applications due to the lack of the support for traffic engineering andQOS. And are limited to either scalability or flexibility or sometimes even both. Even though Diffserve (DS) and Int-serve (IS) provides much better support for QOS but their performance islimited to scalability and flexibility. In short DS and IS approaches are insufficient for support ofQOS enabled applications in highly loaded networks. To overcome this MPLS provides aconnection-oriented framework over the current IP based network which gives an adequatesupport for the required QOS enabled applications

3.2.2 Traffic Engineering (TE)

Traffic Engineering was needed due to the random nature of the Internet where the abilityis required to define routes dynamically, an important result of this process is the avoidance ofcongestion on any one path (Imran, 2009, p. 16). Plan resource commitments on the basis ofrequired QOS which includes known demands and optimized network utilization is known astraffic engineering. Why it is needed because the conventional IP network provides a poorsupport for traffic engineering because its core protocol IP (Internet Protocol) was never designedwith QOS in mind rather it was designed for education and research purpose. Important thing isthat how to allocate the available network resources in order to optimize the performance of the

network when the network has to sustain heavy traffic loads while having limitedresources. The destination based forwarding paradigm cases congestion in the conventional IPnetworks because some links are heavily congested while the oth