EXAMINING THE BEHAVIOR AND PERFORMANCE OF SDN-ENABLED VLAN IN SWITCH NETWORK
BY
MOHAMUD ABDULKADIR AHMED
A dissertation submitted in fulfilment of the requirement for the degree of Master of Information Technology
Kulliyyah of Information and Communication Technology International Islamic University Malaysia
SEPTEMBER 2019
ii
ABSTRACT
The Virtual Local Area Network (VLAN) has been around for over three decades and make use of in campus and enterprise networks as one of the most preferred systems virtualisation solution. As a result of the benefits accomplished by utilising VLAN, network operators and administrators have been using it for creating their networks until today and have even extended it to handle the networking in a cloud computing system.
Moreover, VLAN is a modern technology that can set up logical networks independent of physical network framework. The outcomes of previous researches have predicted that a Virtual Network is needed, which eventually produces a VLAN. However, their configuration is a complicated, tedious, time-consuming, and error-prone process. The present network standard is not adaptable, dependence on vendors is significant because the feature of the forwarding plane (also called data plane) and control plane remain in one device bundle. While, Software-Defined Networking (SDN) seems like a feasible substitute network architecture that permits separation of information plane, as well as the control plane feature on the devices. It is a promising solution for handling the challenges mentioned above in VLAN management. In this dissertation study, the first implementation SDN-enabled VLAN by leveraging OpenFlow. Next, the study investigates the performance of SDN-Enabled VLAN with Access VLAN. Besides, the study examines the packet processing behaviour in transmission both SDN-enabled switch and conventional switch. The result of the research indicates that SDN-Enabled VLAN offers more efficient configuration, far better network performance, and also reduced latency in packet transfer between VLAN segmentation
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ثحبلا ةصلاخ
دجاوتت بشلا هك ةيللمحا
ةيضاترفلاا (VLAN) تابكشلا رثكا نم برتعتو دوقع ةثلاث نم رثكا ذنم ةيضاترفلاا ةلضفلما
ةمدختسلماو في
يرثك نم تاعمالجا تاسسؤلماو
. لظ اولغشم تاكبشلا نومدختسي
اذه
عونلا نم تاكبشلا في
ءاشنا متهاكبش تىح
مويلا كلذو الم اله نم دئاوف هيرثك . لب اوماقو اضيا ب عيسوت
اهقاطن لماعتلل عم
تاكبشلا في
مظن ةبسولحا
ةيباحسلا (CLOUD COMPUTING).
ةولاع ىلع كلذ
،
نإف VLAN راطإ نع ة لقتسم ةيقطنم تاكبش دادعإ اهنكيم ةثيد ح ةينقت يه ةكبشلا يلعفلا . تأبنت ضعب ثابحلاا ةقباسلا
نا كانه ةجاح لىا اذه عونلا نم تاكبشلا نم
لجا جاتنا
هكبش لمح ةي ةرهاظ لاا نا اهئانب اهتمجربو برتعت
هيلمع ةبعص ةلممو ةكلهتسمو تقولل
امم اهلعيج ةضرع
ءاطخلال عجريو
كلذ لىا نا رايعم ةكبشلا ليالحا يرغ لباق فيكتلل
، دامتعلااو ىلع
ينعئابلا مهم نلأ
ةزيم لودج لاسرلاا ( ىمستو اًضيأ لودج تناايبلا ) لودج مكحتلا نزتخ ةمزحك في سفن زاهلجا . لثتم
تاكبشلا هفرعلما
ايمجرب (SDN) مكحتلا ىوتسم نع تامولعلما ىوتسم لصفب حمست هليدب ةيكبش هئيب في زهجلاا ة تيلاو برتعت لح دعاو ةلجاعلم يادحتلا ت ةروكذلما اقباس
في ةرادإ ةكبش ةيلمح ةيرهاظ
(VLAN). ة ينقتب لمعت ةيرهاظ ةيلمح ةكبش لوأ ذيفنت تم ، ةساردلا هذه في SDN ةدافتسلاا قيرط نع نم
قفدتلا حوتفلما . دعب كلذ
، ثحبت ةساردلا في ءادأ ةكبشلا ةيللمحا ةيرهاظلا ةدوزلما
نقتب
ةي SDN عم
ذفنم VLAN. لك في تناايبلا لقن مزلحا ةلجاعم ةقيرط وا كولس ةساردلا برتتخ ، كلذ ىلع ةولاع نم
لولمحا يذلا لمعي
ةينقتب SDN ةيضاترفلاا ةيلمح ةكبشلا نأ لىإ ثحبلا جئاتن يرشت . يديلقتلا لولمحاو تيلا
لمعت
ةينقتب SDN مزح لاقتنا نمز نم للقت اًضيأو هك بشلا في ءادأ لضفا و ةءافك رثكأ ةئيب رفوت بلا
تنااي في ةكبشلا ةيلمح
ةيضاترفلاا (VLAN)
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APPROVAL PAGE
I certify that I have supervised and read this study and that in my opinion, it conforms to acceptable standards of scholarly presentation and is fully adequate, in scope and quality, as a dissertation for the degree of Master of Information Technology.
………..
Adamu Abubakar Ibrahim.
Supervisor
………..
Akram M Z M Khedher Co-Supervisor
I certify that I have read this study and that in my opinion it conforms to acceptable standards of scholarly presentation and is fully adequate, in scope and quality, as a dissertation for the degree of Master of Information Technology.
………..
Mohd.Izzuddin Bin Mohd.Tamrin Examiner
This dissertation was submitted to the Department of Information Systems and is accepted as a fulfilment of the requirement for the degree of Master of Information Technology.
………..
Nurul Nuha Abdul Molok
Head, Department of Information Systems
This dissertation was submitted to the Kulliyyah of Information and Communication Technology and is accepted as a fulfilment of the requirement for the degree of Master of Information Technology.
………..
Abdul Wahab Bin Abdul Rahman Dean, Kulliyyah of Information and Communication Technology
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DECLARATION
I hereby declare that this dissertation is the result of my investigations, except where otherwise stated. I also declare that it has not been previously or concurrently submitted as a whole for any other degrees at IIUM or other institutions.
Mohamud Abdulkadir Ahmed
Signature ... Date ...
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COPYRIGHT PAGE
INTERNATIONAL ISLAMIC UNIVERSITY MALAYSIA
DECLARATION OF COPYRIGHT AND AFFIRMATION OF FAIR USE OF UNPUBLISHED RESEARCH
EXAMINING THE BEHAVIOR AND PERFORMANCE OF SDN-ENABLED VLAN IN SWITCH NETWORK
I declare that the copyright holders of this dissertation are jointly owned by the student and IIUM.
Copyright © 2019 Mohamud Abdulkadir Ahmed and International Islamic University Malaysia. All rights reserved.
No part of this unpublished research may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise without prior written permission of the copyright holder except as provided below
1. Any material contained in or derived from this unpublished research may be used by others in their writing with due acknowledgement.
2. IIUM or its library will have the right to make and transmit copies (print or electronic) for institutional and academic purposes.
3. The IIUM library will have the right to make, store in a retrieved system and supply copies of this unpublished research if requested by other universities and research libraries.
By signing this form, I acknowledged that I have read and understand the IIUM Intellectual Property Right and Commercialization policy.
Affirmed by Mohamud Abdulkadir Ahmed
……..……….. ………..
Signature Date
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ACKNOWLEDGMENTS
In the name of Allah, the Most Gracious and the Most Merciful Alhamdulillah, all praises to Allah for the strengths and His blessing in completing this thesis.
My deepest gratitude goes to my beloved parents; Mr Abdulkadir Ahmed and Mrs Zahra Hayir who granted me the gift of their unwavering belief in my ability to accomplish this goal: thank you for your support and endless love, prayers and encouragement.
Special appreciation goes to my supervisor, DR Adamu Abubakar Ibrahim, for his continuous support, encouragement, and leadership. His invaluable help of constructive comments and suggestions throughout the experimental and thesis works have contributed to the success of this research. Also, I would like to express my gratitude to the Dean of the Kulliyyah of Information and Communication Technology PROF.
Abdul Wahab Bin Abdul Rahman, Head Department of Information Systems ASST.
PROF. DR. Nurul Nuha Abdul Molok, Deputy Dean (Postgraduate and Research) ASSOC. PROF. DR. Abdul Rahman Ahlan and all the technicians and office staffs of KICT for their co-operation
Finally, I wish to express my appreciation and thanks to those who provided their time, effort, and support for this project. To the members of my dissertation committee, thank you for sticking with me.
.
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TABLE OF CONTENTS
Abstract ... ii
Approval Page ... iiv
Declaration ... v
Copyright Page ... vi
Acknowledgments ... vii
List of Tables ... xi
List of Figures ... xii
CHAPTER ONE: INTRODUCTION ... 1
1.1 Background of the Study ... 1
1.2 Statement of the Problem ... 2
1.3 Reserch Objectives ... 3
1.4 Reserch Questions ... 3
1.5 Purpose of the Study ... 4
1.6 Dissertation Organization ... 4
1.7 Chapter Summary ... 5
CHAPTER TWO: LITERATURE REVIEW ... 6
2.1 Introduction ... 6
2.2 Software Defined Network (SDN) ... 6
2.3 Software Defined Network Technologies ... 7
2.4 SDN Architecture ... 9
2.4.1 Overview ... 9
2.4.2 SDN Architecture main Components ... 10
2.5 Open-Flow ... 13
2.6 Traditional Network vs SDN ... 14
2.6.1 SDN Network ... 15
2.6.2 Traditional Network ... 16
2.6.3 The Difference Between Traditional and SDN Network ... 16
2.7 Open-Flow Based SDN ... 17
2.8 SDN Applications ... 19
2.9 Tools for Simulation of SDN ... 20
2.10 Previous Empirical Studies ... 21
2.11 SDN Protocols ... 25
2.12 Local Area Network ... 25
2.13 Evolution Of Lan ... 26
2.14 Components Of Lan ... 27
2.15 Virtual Local Area Network ... 28
2.16 Vlan Grouping Method ... 29
2.17 Vlan Memberships ... 30
2.18 Switch Ports Links ... 31
2.18.1 Access Port ... 31
2.18.2 Trunk Port ... 32
Abstract in Arabic ... iii
ix
2.19 Advantages Of Vlans ... 33
2.20 IEEE 802.1Q ... 34
2.21 Chapter Summary ... 35
CHAPTER THREE: RESEARCH METHODOLOGY ... 36
3.1 Introduction ... 36
3.2 Part one SDN Testbed ... 36
3.2.1 SDN Testbed ... 36
3.2.2 Environment Requirements ... 37
3.2.3 Lab Components ... 38
3.2.4 Installing and Configuring RYU Controller ... 38
3.2.5 Installing and Configuring Mininet ... 39
3.2.6 Installing and Configuring Open vSwitch ... 41
3.2.7 Installing and Configuring Open vSwitch ... 42
3.3 Part two conventional network testbed ... 42
3.3.1 Conventional Network Setup with GNS3 ... 42
3.3.2 GNS3 Simulator ... 42
3.3.3 GNS3 Lab Setup ... 43
3.3.4 GNS3 integration with Cisco IOSvl2 ... 44
3.4 Chapter Summary ... 45
CHAPTER FOUR: IMPLEMENTATION AND PRESENTATION OF RESULTS ... 46
4.1 Introduction ... 46
4.2 Network Topology ... 46
4.3 Testing the Network ... 47
4.4 802.1Q VLAN IN RYU ... 50
4.4.1 VLAN Tagging ... 50
4.4.2 VLAN Matching and Untagging ... 50
4.4.3 Decision Flowchart ... 51
4.5 Result ... 53
4.5.1 Flow Entries in Switch ... 53
4.6 ICMP messages between VLANs ... 54
4.6.1 Case 1: Both hosts are in VLAN 100 ... 54
4.6.2 Case 2: Both hosts are in VLAN 200 ... 56
4.6.3 Case 3: Both hosts are in different VLAN ... 56
4.7 Introduction ... 57
4.7.1 IP Addressing Table ... 58
4.7.2 Configuring VLANs on Switches ... 59
4.7.3 Verifications ... 60
4.7.4 Configuring Trunk ... 61
4.7.5 Verifying Communication between VLANs ... 63
4.8 Latency Comparison ... 64
4.8.1 Comparison of Traditional and SDN Networking ... 66
4.9 Chapter Summary ... 67
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CHAPTER FIVE ... 68
CONCLUSION ... 68
5.1 Introduction ... 68
5.2 Conclusion ... 68
5.3 Future Work ... 69
REFERENCES ... 70
Appendix A: Mininet API Classes ... 73
Appendix B: Mininet Topology Configuration Scripts ... 75
Appendix C: RYU Network Configuration Scripts ... 76
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LIST OF TABLES
Table No. Page No.
2. 1 The feature-based comparison of emulation and simulation tools 20
2. 2 Summary of Literature Review 22
3. 1 Lab Components 38
4. 1 RYU Classes 54
4. 2 IP addresses 58
4. 3 Paired Samples Statistics 65
4. 4 Paired Samples Test 65
4. 5 Comparison of Traditional and SDN Networking 66
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LIST OF FIGURES
Figure No. Page No.
2. 1 SDN Architecture 10
2. 2 SDN vs. Traditional Networking 15
2. 3 Local Area Network 28
2. 4 Trunk link 33
2. 5 802.1Q protocol 35
3. 1 Setup SDN Lab 37
3. 2 Ryu controller 39
3. 3 Mininet Installation 40
3. 4 Mininet Topology 41
3. 5 OpenvSwitch 41
3. 6 Wireshark Application 42
3. 7 Installation Wizard 43
3. 8 Configuration Wizard 44
3. 9 Cisco IOS image installation 45
4. 1 Network topology 46
4. 2 Creation of Network Topology 47
4. 3 Net Test 48
4. 4 Dump Test 48
4. 5 Ping Test 48
4. 6 TCP packet capture 49
4. 7 Network Topology with a Trunk link 52
4. 8 Decision Flow Chart Diagram 52
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4. 9 Push VLAN dump flows 53
4. 10 Pop VLAN dump Flows 53
4. 11Host A1 to Host A3 55
4. 12 Wireshark Trace 55
4. 13 Hosts in VLAN 200 56
4. 14 Wireshark trace 56
4. 15 Different VLAN 57
4. 16 VLAN topology 58
4. 17 Creation and Assigning Ports to VLAN on Switch 1 60
4. 18 Creation and ssigning Ports to VLAN on Switch 2 61
4. 19 Creation and assigning Ports to VLAN on Switch 3 61
4. 20 Trunk link between Switch 1 and Switch 2 62
4. 21 Trunk link between Switch 1 and Switch 2 62
4. 22 PC1 (VLAN100) PING PC3 (VLAN100) 63
4. 23 PC1 (VLAN100) PING PC5 (VLAN100) 63
4. 24 Latency Comparison 64
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CHAPTER ONE INTRODUCTION
1.1 BACKGROUND OF THE STUDY
VLAN administration is just one of the most challenging jobs that network managers deal with. VLAN setup remains a difficult, complex, and also error-prone procedure because network managers require to manually configure layer two switches by utilising standard line interface (CLI) of the device. It would be harder if these tools were located in a different area (e.g., different floors), which indicates that it is tough for network administrators to scale the range of the whole network. Although Cisco has already supported a brand-new protocol named the VLAN Trunking Protocol (VTP) to much better handle their devices, it is still extremely limited in terms of extent and also performance (Zhai, Long, Zhong, & Cui, 2012). Indeed, it requires developing VTP domains to make sure that VTP administration can be transferred. Though, VTP is just available on Cisco switches, such as Catalyst Family. We believe that to deal with these problems; there is a requirement for a VLAN management tool or an application that not only enables network administrators to configure VLAN easily, but also that gives a virtual view for monitoring as well as troubleshooting each VLAN in the network (Lehocine & Batouche, 2017). To address the issues of Traditional VLAN management and its performance, SDN and OpenFlow would be the right solution. This chapter presented a research overview and the background of the study.
In 2011, the Open Networking Foundation (ONF) was formed to promote a new networking paradigm, called Software-Defined Networking (SDN) which changes the way that networks are structured and overseen by presenting a deliberation that decouples the control from the data plane (Mousa, Bahaa-ElDin, & Sobh, 2017).
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However, the concept of software-defined networking (SDN) still in an early stage of development and acceptance of it is at a theoretical stage. The ONF defines SDN “The physical separation of the network control plane from the forwarding plane, and where a control plane controls several devices.” The control plane, represented by a software called the SDN Controller, is responsible for decisions on how to handle network traffic, assuming the role of the “brain” of the network. A typical representation of SDN architecture comprises three layers;
Infrastructure layer: also called the data plane, it contains the forwarding network elements.
Control layer: also called the control plane, it is responsible for programming and
managing the forwarding plane.
Application layer: it contains network applications and services that can introduce new
network features.
The implementation of SDN is dependent subject to on the network strategy embraced by ventures. SDN refers to the majority of the protocols and technologies that work in synchrony to make a general perspective of the network and deliver a centralised, intelligence-based network service, delivery, and control (Nunes, Mendonca, Nguyen, Obraczka, & Turletti, 2014). Recent studies on SDN emphasise on theory part and less on implementation, because of that, we will implement SDN paradigm in Virtual Local Area Network (VLAN) concept.
1.2 STATEMENT OF THE PROBLEM
Networking has become a part of human presence with its broad assimilation throughout several platforms. Home users, as well as business, currently utilise networks to share resources or communicate. The present trend of large systems such
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as business networks as well as cloud computing sees to the requirement for a versatile means of configuring and also forwarding packages between various network nodes.
This is because existing legacy networks have an increased latency actually in forwarding packages because of the demand to do route lookup within their forwarding policy firmware (Kumar et al., 2018). This minimizes the effectiveness of the network as more handling time is sustained and also thus delaying the transportation of packets from a sending out node to a receiving node. This dissertation investigates SDN-enabled VLAN by leveraging OpenFlow. Next, we study the performance of SDN enables VLAN with Access VLAN. Also, we observe the packet processing behaviour in transmission both SDN-enabled switch and conventional switch.
1.3 RESEARCH OBJECTIVES
The study intended to accomplish the following objectives:
1- To evaluate SDN enabled VLAN
2- To investigate the performance of SDN enable VLAN with Access VLAN 3- To examine the packet behaviour in transmission for switch VLAN and
SDN enable Switch Network.
1.4 RESEARCH QUESTIONS
1. How can SDN enable VLAN to be evaluated?
2. What is the performance of SDN enable VLAN with Access VLAN?
3. What is the packet behaviour in transmission for switch VLAN and SDN enable Switch Network?
4 1.5 PURPOSE OF THE STUDY
The primary purpose of this study is to implement SDN-enabled VLAN by leveraging the programmable network. Next, we investigate the performance of SDN enable VLAN with Access VLAN. Besides, we examine the packet processing behaviour in transmission both SDN-enabled switch and conventional switch. By deploying virtual testbed prototype, we how our implementation works and evaluate network latency in both environments (SDN and Traditional Network)
1.6 DISSERTATION ORGANIZATION This thesis is organized as follows:
Chapter 1: Is an introductory chapter that presents the dissertation background, problem statement, outlines research questions, and objectives.
Chapter 2: Is the literature review chapter, which introduces the fundamental concept that readers require to understand the overall dissertation purpose. Furthermore, we explain software defined network or SDN architecture and how is it different from current conventional network architecture. We also discuss Virtual Local Area Network (VLAN) and its importance in networking. Finally, we introduce the difference between SDN-enabled VLAN and traditional VLAN and how it can be improved by implementing SDN concept.
Chapter 3: Elaborates the details and steps of the dissertation methodology that have been conducted to curry this research work. The section describes how this research has been accomplished. Besides, we explain some of the related theory needed to understand more about the content of this experiment work and methodology used for implementing this research, such as software’s and platform used.
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Chapter 4: Presents the implementation and results. Besides that, we demonstrate step by step experiment phases with the outcome of each phase result.
Chapter 5: This chapter provides the conclusion and summary of the result followed by a recommendation.
1.7 CHAPTER SUMMARY
This chapter has presented and discussed the background of the study. It explained software defined network or SDN features with and why it is essential in the networking industry, Virtual Local Area (VLAN) concept was included and how it requires improvement when it comes to network management. Additionally, the statement of the problem was discussed. Furthermore, the importance of SDN-enabled VLAN, why digital technology is vital to the educational environment, definitions of concepts were included in numerous sources. Additionally, the statement of the problem was discussed, as this study set to evaluate SDN-enabled VLAN and study the performance of SDN enable VLAN with Access VLAN. The significance of the study followed; we observe the packet processing behaviour in transmission both SDN-enabled switch and conventional switch. This chapter also presented the research questions, objectives, and the significance of the study. We observe the packet processing behaviour in transmission both SDN-enabled switch and conventional switch. Finally, the limitations of the study were mentioned, followed by brief definitions of the key terms in this study.
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CHAPTER TWO
LITERATURE REVIEW AND THEORETICAL BASIS
2.1 INTRODUCTION
This chapter aims to deliver the necessary background to understand the rest of the thesis. The descriptions are given in this chapter present a general view of the concepts and are focused on the most relevant details related to this thesis work, which includes software-defined networking (SDN), traditional network, implementation of SDN, the architecture of SDN, and finally virtual local area network.
2.2 SOFTWARE DEFINED NETWORK (SDN)
SDN is becoming widespread in recent years. The term SDN is a new paradigm for networking industries, and network researchers which encompassing several types of network technology that aimed at modelling the network to become flexible and agile (Medlin Benisha, 2016). Designing and managing networks have turned out to be more innovative over the past few years with the aid of SDN. The core goal of SDN is for the system to be open and programmable (Eliazer, 2017). For example, if an organization has to do some network behaviour, it can develop or install an application to do what it needs.
These applications can be standard networking functions such as traffic engineering, Security, QoS, Routing, Switching, monitoring, and Load Balancing.
When it comes to the definition of SDN, it means different things to different people.
Everyone thinks about SDN from their perspective, depends on their role in IT. Ivan Pepelnjak, ipSpace.net defines SDN as “programmable networks. Open Network Foundation (ONF) an organization that devoted the furtherance and implementation of
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SDN describes as “The physical separation of the network control plane from the forwarding plane, in which a control plane controls several nodes” (ONF, n.d.).
The SDN control plane resides in software program outside to the switches. Forwarding decisions are made by the software control plane (the controller) and also programmed into the switches. Network actions can be changed through software updates with SDN (Mishra & AlShehri, 2017). Compared with equipment, the software program is simple, quick, and cost-effective to upgrade or replace (Nunes et al., 2014).
SDN makes it possible for researchers to explore new ideas, as well as it enables operators to release new services and also customize the network to satisfy application requirements. SDN provides advantages throughout various networking domain names (Mishra & AlShehri, 2017). Applications that make use of SDN have been shown or proposed for venture networks, data centre, backbones/WANs, as well as home networks (Ciena & Networks, 2016). SDN concentrate on four key features:
• Disaggregation of the information plane (data) to control plane
• A centralized controller and view of the network
• Open interfaces among the devices in the control plane (controllers) and those in the data plane
• The programmability of the network by external applications
2.3 SOFTWARE DEFINED NETWORKS TECHNOLOGIES
Over the last ten years, there has been a significant rise in the interest that IT industries have shown in Software-Defined-Networking (SDN) at the same time the number of SDN associated announcements that IT vendors have made. Given that SDN technologies are new to IT organizations such as OpenFlow (Kim & Feamster, 2013).
OpenFlow (OF) is a protocol that allows the implementation of the SDN concept and is
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considered one of the first SDN network standards (Braun & Menth, 2014). It initially defined the communication protocol in SDN environments that permits the SDN Controller to directly communicate with the data plane (sometimes called the forwarding plane) of network devices such as layer two switches and routers, by virtual or physical (Nunes et al., 2014).
(Metzler, 2015) in 2015 revealed that several factors are driving respondents to interest in SDN such as the desire to utilize network resources and to execute traffic with an end-to-end view of the network. Other respondents thought that SDN would help reduce the complexity of network management (O’Dowd, n.d.). However, the respondent also pointed out several factors were hindering their interest in SDN. Some of the hinders to SDN adoption include immaturity of current SDN products and enabling technologies that required time to overcome, and fluke of a compelling business case. The respondents also predicted the primary focus of SDN and indicate that over the next two to three years, SDN deployment will be in the data centre as well as WAN, and campus network. According to Braun, SDN addresses the deficiency of programmability in traditional network architecture and enables flexibility network innovation by decoupling data form control plane (Braun & Menth, 2014). In 2008, (McKeown et al., 2008) proposed the OpenFlow switch.
The reason behind the creation of open flow was to foster the innovation of the campus network by allowing researchers to run an experimental test on their network ideas (McKeown et al., 2008). Also, Network Operating System called NOX was proposed in the same year but, officially launched in 2009. NOX aims to present a centralized programming model that written high-level abstractions (Gude et al., 2008).
These two technologies, OpenFlow and NOX, paved the definition of SDN architecture.
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It called The NOX based network initially (Alvizu et al., 2017). SDN has four main functionalities as follow;
A. Control plane and data plane separation
B. A centralized manager and view of the network
C. Open interfaces among the devices in the control plane and the data plane D. Use of external application to support the programmability feature of the network
2.4 SDN ARCHITECTURE 2.4.1 Overview
In Internet Procedure (IP) networks, performing transportation and also control measures within networking tools, indeed contributes to its excellent achievement in early days. Nevertheless, its versatility in administration, as well as scalability to emerging applications, suffer from more and more challenges nowadays (Horvath, Nedbal, & Stieninger, 2015). What makes the scenario even worse is that the up and down integration turns into one of the most significant obstacles to fast developments and also relentless advancements on both methods and infrastructures.
To this point, SDN has been recommended, with a brand-new architecture that decouples the control aircraft as well as the information plane of the network (Jammal, Singh, Shami, & Li, 2014). Ideally, the underlying facilities can function as essential as an automate that refines obtained packages with pre-defined activities, according to policies set up by the rationally central controller. Such a splitting up of control procedures from forwarding devices not just enable modern technologies in both sides to progress separately and a lot faster, yet likewise streamlines the administration and setup of the entire network.
10 2.4.2 SDN Architecture main components
Figure 2.1 highlights the rational framework of an SDN. The dominant controller does major complicated attributes, consisting of directing (routing), identification, and plan affirmation.
Figure 2. 1 SDN Architecture Source: (William Stallings, 2016)
The central plane consists of the SDN Control Plane and has a number of SDN servers.
The SDN control application specifies the information stream that takes place in the
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SDN Information Plane. Every single flow with the network has to initially obtain authorization from the control application, which validates the network plan to permits the communication (Benzekki, El Fergougui, & Elbelrhiti Elalaoui, 2016). If the controller permits a stream, it calculates a path for the flow to take, as well as consists of access for specific flow in every single switch in the network and their path.
Altogether the advanced attributes included by the controller application, switches handle stream tables whose programs can be inhibited simply by the control plane. Data exchange between the network devices and the controller uses a conventional protocol as well as API. The majority of this user interface utilizes OpenFlow requirements, evaluated consequently.
The SDN architecture is extremely multipurpose; it has the ability to run with different kinds of switches as well as at various protocol layers (Foukas, Marina, &
Kontovasilis, 2015). SDN controllers and switches can be applied for the Open Systems Interconnection model (OSI model) segments such as Ethernet switches (Layer two), Network (Layer three), transport (Layer four) switching, or application layer Switching and also Routing. SDN trusts upon the normal functions located on networking tools, which primarily include forwarding packets based upon some flow interpretation.
In an SDN framework design, a switch executes the adhering to features:
• The switch envelops as well as forwards the original package of entry to an SDN controller, allowing the controller to choose whether the entry needs to be included into the switch entry table.
• The Switch forwards incoming packages out the perfect port based on their entry table. The entry-flow table might contain top import information determined by the SDN application.
