A COMPARATIVE ON PERFORMANCE OF VOIP USING POWER LINE AND WIRED (UTP CAT5)



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A COMPARATIVE ON PERFORMANCE OF VOIP USING POWER LINE AND WIRED (UTP CAT5) BY KHAINORIZAN BINTI KHALID BACHELOR OF SCIENCE (Hons) DATA COMMUNICATION AND NETWORKING Thesis proposal submitted in fulfillment of the requirements for BACHELOR OF SCIENCE (Hons) DATA COMMUNICATION AND NETWORKING Faculty of Information Technology and Quantitative Science Universiti Teknologi MARA MEI 2006 i

A COMPARATIVE ON PERFORMANCE OF VOIP USING POWER LINE AND WIRED (UTP CAT5) BY KHAINORIZAN BT KHALID 2003323445 This project is submit to the Faculty of Information Technology and Quantitative Science MARA University of Technology In partial fulfillment of requirement for the BACHELOR OF SCIENCE (Hons) DATA COMMUNICATION AND NETWORKING Approve by the Examining committee: EN.KAMARUL ARIFFIN BIN ABD BASIT Project Supervisor EN.FAROK BIN HJ.AZMAT University of Technology MEI 2006 ii

Faculty of Information Technology and Quantitative Science Universiti Teknologi MARA MEI 2006 iii

ACKNOWLEDGEMENT In the name of Allah, the Most Gracious and Most Merciful All praises to the Almighty Allah S.W.T for His blessings which has given me patience, strength and ability to complete this project. I would like to express my sincere gratitude to those who had involved in contributing their help and support either directly or indirectly in the development of this project. It has been my good fortune to have the advice and guidance from many educated people, their knowledge and skills help in enhancement of this project in so many ways. First and foremost, my deepest appreciation and gratitude go to my supervisor, En. Kamarul Ariffin bin Abd Basit, for his guidance, encouragement, ideas, tolerance and lots of support that led to the completion of this project. It is such a wonderful gift to have the opportunity to learn and gain experience from such a skilled and experienced supervisor. Thank you to my examiner, En. Farok bin Hj.Azmat for his guidance and support. Last but not least, special gratitude goes out to my family for showing their concern and supporting me all the way right up to the completion of this project. Thank you. iv

Abstract Power-line networking is one of several ways to connect the computers in home. It uses the electrical wiring in house to create a network. Power-line networking is based on the concept of no new wires. Because it requires no new wiring, and the network adds no cost to electric bill, power-line networking is the cheapest method of connecting computers in different rooms. Small office user and home user (SOHO) have problems in creating a communication medium between them. Besides that, the user needs high-quality internet call with highavailability at low cost. So on this project paper, we would like to do a comparative study on performance of VoIP using Power line and wired (CAT5) to find the best result for creating communication at low cost. So this project paper is want to analysis the performance VoIP using Power line and to compare it with wired.it is testing only in direct LAN. The performance also focuses on measurement of the performance based on packet loss, jitter, delay throughput and bandwidth. Measurement performance on packet loss, jitter and delay is using NetQuality whereas throughput and bandwidth were using NetstatLive. For get the persist result, testing are doing in 15 time for a week for jitter, packet loss and delay.10 time per week for throughput and bandwidth.. The average of the result will compare with performance VoIP using power line and with wired. The conclusion for this comparative the performance communication of the wired performance is better than power line. This is proven from the QoS performances that had been analyzed. It is Analyze quality of voice in more parameter and get the persistence result using the better tools with quality voice, It is recommended to future works not only focused on analysis to Direct LAN. Also focus on analysis the performance at Indirect LAN such as at other block or layer and It is recommended to future works to testing at the other application telephony such as soft phone v

TABLE OF CONTENTS ACKNOWLEDGEMENT ABSTRACT TABLE OF CONTENTS LIST OF FIGURES LIST OF TABLES LIST OF GRAPHS LIST OF ABBREVATIONS iv v vi x xi xii xiii CHAPTER 1: INTRODUCTION 1.1 Introduction 1 1.2 Project Background 2 1.3 Problem Description 2 1.4 Project Objective 3 1.5 Project Scope 3 1.6 Project Significant 4 1.7 Summary 4 CHAPTER 2: LITERATURE REVIEW 2.1 Introduction 6 2.2 Power Line 6 2.2.1 What is Digital Power Line 6 2.3 Home Plug Power Line 7 2.4 PHY and MAC Layers in Home Plug 8 2.5 Voice over Internet Protocol 10 2.5.1 What are VoIP /Internet Voice? 10 2.5.2 How voip work 11 2.5.3 The benefits of Voice over IP 12 vi

2.6 Internet Telephony 13 2.7 Type of communication technology testing 13 2.7.1 Power line 13 2.72 Wired (UTP CAT5) 14 2.8 Type of Quality of VoIP 14 2.8.1 Throughput 14 2.8.2 Bandwidth 14 2.8.3 Jitter 15 2.8.4 Packet loss 15 2.8.5 Delay 15 2.9 Brief Description of all Known Similar and Relevant On-Going Projects 16 2.9.1 Design and implementation of an end to end communication system for smart appliances using power line communication 17 2.9.2 High-Performance Periodic Contention-Free Multiple-Access Protocol for Broadband Multimedia Power line Communications 17 2.9.3 Broadband power line 19 CHAPTER 3: METHODOLOGY 3.0 Introduction 23 3.1 Research Approach and Methodology 25 3.2 Planning 26 3.2.1 Research and Data Collection 26 3.2.2 Software and Hardware requirement 26 3.2.2.1 Software Requirement 27 3.2.2.2 Hardware Requirement 27 vii

3.3 Implementation 28 3.3.1 Implement the project 28 3.3.2 Hardware setup 28 3.3.3 Software installation 30 3.3.3.1 Power line Home plug 31 3.3.3.2 Software tools installation 35 3.4 Testing 35 3.5 Analysis 36 3.6 Comparisons 36 3.7 Summary 37 CHAPTER 4: ANALYSIS AND RESULT 4.1 Introduction 4.2 Analysis Comparison Performance VOIP Using With And Without Using Home Plug Powerline. 38 4.2.1 Throughput Result 38 4.2.1.1 Incoming result 39 4.2.1.2 Outgoing result 40 4.1.2 Bandwidth Result 41 4.1.2.1 Incoming result 42 4.1.2.2 Outgoing result 43 4.1.3 Maximum Delay Result. 44 4.1.4 Maximum jitter result 45 4.1.5 Data loss result. 47 4.2 Comparison to VOIP Performance with Powerline and Without Power Line 48 4.2.1 Comparison Bandwidth and Throughput 48 4.2.2 Comparison to Jitter. 49 4.2.3 Comparison to packet loss 49 4.2.4 Comparison to delay 50 viii

4.3 Summary 50 CHAPTER 5: CONCLUSION AND RECOMMENDATION 5.1 Conclusion 51 5.2 Recommendation 53 5.3 Summary 53 REFERENCES 54 APPENDIX A 57 APPENDIX B 63 ix

LIST OF FIGURES Figure 2.1 Conversation process that takes place at the transmission Figure 2.2 OFDM waveform generation (I-Meng Chen, Nov 2003) Figure 2.3 Channel access of MAC Layer Figure 2.4 Data Packet Figure 3.0 System Development Life Cycle (SDLC) Figure 3.1 Project Methodology Phases Diagram Figure 3.2 Testing Power line model for direct LAN Figure 3.3 Testing Wired line model for direct LAN Figure 3.4 Shortcuts to PowerPacket Configuration Utility Figure 3.5 Device dialog screen Figure 3.6 Progress bar link Quality is Excellent Figure 3.7 Network Dialog Screen Figure 3.8 Security Dialog Screen Figure 3.9 Advanced dialog screen x

LIST OF TABLES Table 4.0 Table 4.1 Table 4.2 Table 4.3 Table 4.4 Table 4.5 Table 4.6 Incoming Throughput Outgoing Throughput Incoming Bandwidth Outgoing Bandwidth Maximum Delay result Maximum Jitter Result Data loss result xi

LIST OF GRAPHS Table 4.0 Table 4.1 Table 4.2 Table 4.3 Table 4.4 Table 4.5 Table 4.6 Incoming Throughput Outgoing Throughput Incoming Bandwidth Outgoing Bandwidth Maximum Delay result Maximum Jitter Result Data loss result xii

LIST OF ABBREVIATIONS SOHO LAN VOIP DPLC PLC QOS OFDM VoIP DPL HFCPN CU PHY MAC IFF IP PC PSTN ISP BPL Small Office Home Office Local Area Network Voice over internet protocol Digital Power Line Communication Power Line Communication Quality of Services Orthogonal Frequency Division Multiplexing Voice over Internet Protocol Digital Power Line High Condition Power Network Conditioning Unit Physical Layer Medium Access Control Fast Fourier Transform Internet Protocol Personal Machine Public Switch Telephone Network Internet service Provider Broadband Power Line xiii

CHAPTER 1 INTRODUCTION 1.1 Introduction Nowadays, small office home office (SOHO) users and home users can minimize the cost of installing new wiring or cabling to support a LAN. An alternative is to implement a no new wires LAN.This is normally either a wireless (WLAN) or one that utilizes existing electrical mains wiring. In this project, mains borne network are referred to as Digital Power Line Communication (DPLC) LANs. Digital Power Line Communications (DPLC) is the usage of electrical power supply networks for communications purposes. In this case, electrical distribution grids are additionally used as a transmission medium for the transfer of various telecommunications services. The main idea behind DPLC is the reduction of cost and expenditure in the realization of new telecommunications networks. Nowadays, internet is becoming an important communication tool to the user. Therefore, the Internet Telephony (IT) had made it possible to have a voice conversation over the internet or over a dedicated internet protocol (IP) network instead of dedicated voice transmission lines. This allows the elimination of circuit switching and associated waste of bandwidth. Instead, packet switching is used where IP packets with voice data are sent over the network only when data needs to be sent. Therefore, Voice over IP (VoIP) has been a front-runner for companies looking to take advantage of IP. There are cost benefits, however with VoIP there are challenges to the performance. The biggest challenge in transitioning from traditional circuit-switched voice systems to the new, more economical voice over IP packet- 1

switched technologies, is obtaining adequate Quality of Service (QoS) over the network. QoS in a network must be adapt to prioritize traffic types; interpreting traffic types (applications running over IP); and then conveying them over the network so that QoS requirements can be met. 1.2 Project Background Digital Power Line Communication enables data travel through electrical wires rather than telephone wires network, which carries digital signal to terminal device using Digital Power line. It is provides the transmission of data to users over the same lines that bring electric power to homes and businesses. The speed for transmission is one mbps. This would free your telephone from only voice communication purposes. (whatis.com) The Digital Power Line can be used to make a VoIP at homes and business. This project paper is to analysis the performance of VoIP using Digital Power Line is to identifies the source of problems. The performances can be analyzed by the VoIP s quality of service (QoS) parameters, which are packet loss, delay, jitter, throughput and bandwidth. Those parameters are will be discussed later. 1.3 Problem Description Small office user and home user (SOHO) have problems in creating a communication medium between them. It is because the technology needs a wiring LAN. This factor has made the small office user and home user paying more to use that technology. Besides that, the user needs high-quality internet call with highavailability at low cost. The VoIP network is the call technology the user need, but there are many factors a user has to face before using this technology. The VoIP is currently using Power Line which the problems to face are some packets are lost and 2

needs to be resent which later introducing time delay. Therefore, this project is conducted to measure performance of VoIP over Digital Power Line technology and a comparative study on performance of VoIP using Power line and wired (CAT5). Comparative is measured and once the cause is identified, a specific task can be taken to improve and get the quality. 1.4 Project Objective This project is done with the guidelines of the main objectives. It is important to state the objectives of the project clearly; it is to ensure the project is kept on track. Analysis on Voice over Internet Protocol (VoIP) Internet Telephony performance based on QoS parameters are divided into four (5) objectives. To introduce and implement digital power line communication network as an alternative way in LAN communication. To test VoIP Internet Telephony over power line use yahoo messenger as internet telephony To test VoIP over Ethernet LAN wired (CAT5) use Yahoo messenger as internet telephony To analyze VoIP performance in direct LAN based on the Quality of Service (QoS) parameters using Digital Power line and wired (UTP CAT5). To compare performance VoIP with power line and without power line (wired) 1.5 Project Scope This project is to allow data travel through electrical wires rather than telephone wires network, which carry digital signal to terminal device using Digital Power 3

Line. The focus on VoIP over Power Line digital and analysis performance are on the VoIP packet loss, delay, jitter, throughput and bandwidth through Direct LAN. 1.6 Project significant The project significant is to make users understand the backbone of Voice over Internet Protocol. Beside that, it is will easier like small office to understand each type of the QoS parameter that are taking effect in VoIP network and can make this project paper as reference for their study. Chapter 1: Introduction In this chapter, we will discuss the introduction of the topic generally. It contains the overviews of the problem, objectives, scope and significance of the project. Chapter 2: Literature Review In this chapter, we will focus on the literature review where we will study about Internet Telephony based on the QoS parameters, the definition of the VoIP Internet Telephony is clearly defined and some works which have been done by other that are related or share several similarities to our project. In addition, we included some study on the related topic that support in development of this project. Chapter 3: Methodology This chapter, a briefing about the methodologies employed in this project is provided. Also discussed are the methods used from the beginning until the end of the project. Chapter 4: Finding and Results 4

This chapter described the implementation and testing that was done in carrying out this study. The analysis to VoIP performance that has been performed and accomplish is discuss to gather the results. Chapter 5: Conclusion and Recommendation This is the last topic that concludes the study carried out and provides recommendation and suggestions that carry out in the near future. 5

CHAPTER 2 LITERATURE REVIEW 2.1 Introduction This chapter will discuss on the review of the research and the related literatures on the several areas of the study. There are include the definition of pertinent technical terminologies that are used into complete this research such as Power line and we are identified the meaning of the voice over IP (VoIP),internet telephony, quality of service (QoS) in the VoIP network. Therefore, this chapter will review some similar studies, the description of the problem, overview different approaches made by previous people and make comparison between our project and those similar studies. 2.2 Power Line 2.2.1 What is power line? Digital Power Line, developed by Northern Telecom and United Utilities, is capable of transmitting data at a rate of 14Mbps over existing electricity infrastructure. Through "conditioning" of the existing electricity infrastructure, electrical utilities can transmit regular low frequency signals at 50 to 60Hz and much higher frequency signals above 14MHz without affecting either signal. A transmission power of about 10 watts is often sufficient to overcome distances of more than 500 kilometers. According to the searchnetworking.com definition powered by whatis.com, Digital Power Line (DPL) is the usage of electrical power supply networks for communications purpose. In this case, electrical distribution grids are additionally 6

used as a transmission medium for the transfer of various telecommunication services. Using the Internet's TCP/IP protocol, companies using DPL across the mains electricity grid plan to deliver data at speeds up to 1Mbps. DPL would allow a user to get Web pages and other Internet information over power lines with a 24-hour continuous connection (since your power lines are always connected). This would free your telephone from sole voice use. In addition, since many home appliances are attached to the power system, they could easily be addressed as Internet devices when plugged in. The lower frequency signals carry power, while the higher frequency signals can transmit data. Digital Power Line uses a network, known as a High Frequency Conditioned Power Network (HFCPN), to transmit data and electrical signals. A HFCPN uses a series of Conditioning Units (CU) to filter those separate signals. The CU sends electricity to the outlets in the home and data signals to a communication module or "service unit". 2.3 Home Plug Home Plug is standard body for power line communication. The Home Plug technology uses electrical grids, which are already available inside the walls to transmit data from computer to computer. Home Plug technology modulates computer data in a way to enable them use power grid as a medium of transmission from point to point. Using this technology, two computers have a virtual Ethernet connection without the need to be physically connected to each other. The current Home Plug standard allows for speeds up to 14 Mbit/s although they are developing Home Plug AV which allows for speeds greater than 100 Mbit/s, suitable for HDTV and VoIP. Digital power line is capable of transmitting data at rate of 14Mbps over existing electricity infrastructure. These applications occur within a single building with both ends of the communications link within the same building. 7

The building might be a house, an apartment block or an office building. The path over which the transfer of data occurs within these buildings is relatively short - typically it is less than 200 m between devices. This has been possible due to the relatively low power levels necessary to communicate over the comparatively short (cabling) distances within a building 2.4 Physical and Medium Access Control Layers in Home Plug According to Congency.com, their power line networking includes a physical layer (PHY) and medium Access Control (MAC) layer. The PHY layer implements the modulation techniques, the coding and basic packet formats. The PHY uses packetbased Orthogonal Frequency Division Multiplexing (OFDM) as transmission technique. Orthogonal Frequency Division Multiplexing (OFDM) is the basic transmission technique used by the Home Plug. OFDM is well known in this literature and in industry. Also taken from Congency.com, the choice of Medium Access Control (MAC) protocol provides a different set of challenges. Home networks should be able to support a diverse set of applications ranging from simple file transfer to very high QoS demanding applications such as Voice over IP (VoIP) and streaming Media. The Home Plug MAC is built to be able to support a diverse set of applications ranging from simple file transfer to seamless integrated with the physical layer and addresses these needs. The MAC/PHY provides per-packet equalization and efficient access to shared power line medium. The MAC/PHY provides per-packet equalization and efficient access to the shared power line medium. Beside that, a priority resolution-signaling scheme enables latency-sensitive applications such as VoIP and multi-player gaming. 8

Transmit Data FEC Tone mapping IFFT Time Domain Processing X Power line Figure 2.1: Conversation process that takes place at the transmission Figure 2.1 illustrates the conversation process that takes place at the transmitter. Forward Error Correction (FEC) redundantly encodes the data to compensate for harsh channel characteristics. The encoded data is mapped onto a set of tones which may be all available tones or a pre-agreed upon subset. OFDM modulation, generated using a fast Fourier transform (FFT) processor, convert signal in the frequency domain to the time domain. As for the inverse FFT, it is applied at the transmitter, produces an OFDM symbol. Figure 2.2: OFDM waveform generation (I-Meng Chen, Nov 2003) According to figure 2.2 OFDM waveforms are typically generated using an inverse fast fourier transform FFT (IFFT) in which the frequency domain points consist of the set of complex symbols that modulate each carrier. The result of the IFFT is called an OFDM symbol. Each symbol has duration equal to the reciprocal of the sub 9

carrier spacing and generally a long time compared to the data rate. At the receiver, the data can be recovered via a forward FFT, which will be converted back to the frequency domain. Figure 2.3: Data Packet Each data packet carries a series of OFDM symbols (as shown in Figure 2.3). The packet consists of a start-of-frame delimiter, the payload, and an end-of-frame delimiter. A response delimiter is transmitted to indicate whether the transmission was successfully received. From the website of Aztech (http://aztech.com/press/2004/homplug%20coverage/presscoverage.htm;), the frame control indicates whether the delimiter is a start of frame, end of frame, or response delimiter. Start of frame delimiters specify the duration of the payload to follow, while the other delimiters implicitly define where the end of transmission lies. Thus, if a receiver can decode the frame control in the delimiter, it can determine the duration for which the channel will be occupied by this transmission, and it sets its VCS until this time ends. If it cannot decode the frame control, the receiver must assume that a maximum-length packet is being transmitted and sets the VCS accordingly. In this case, it may subsequently receive an end-of-frame delimiter and thus be able to correct its VCS. 10

2.5 Voice over Internet Protocol 2.5.1 What are VoIP /Internet Voice? In the website of http://www.fcc.gov/voip/, VoIP allows us to make telephone calls using a computer network, over a data network like the Internet. VoIP converts the voice signal from your telephone into a digital signal that travels over the internet then converts it back at the other end so we can speak to anyone with a regular phone number. When placing a VoIP call using a phone with an adapter, we hear a dial tone and dial just as you always have. VoIP may also allow you to make a call directly from a computer using a conventional telephone or a microphone. From the website of www.247access.co.za/pap/glossary.html, VoIP is delivered using the Internet Protocol (IP). IP is a term used in IP Telephony for a set of facilities for managing the delivery of VoIP information using the IP. In general, this means sending VoIP information in digital form in discrete packets rather than in the traditional circuit-committed protocols of the Public Switched Telephone Network (PSTN). According to Darlington (2004), there are many benefits of VoIP, as there will be significant financial savings on running the network itself. One infrastructure carrying both data and voice, provided by one supplier, can be managed, maintained and upgraded much more efficiently than two separate networks for voice and data. 2.5.2 How VoIP work. According to Olivar (2004), VoIP enables users from different parts of the world to engage in voice conversations, even long distance ones, without having to pass through part or all of the telecommunications facilities. Using VoIP, a person could engage in international voice conversations without having to pass through and pay for the use of the international gateway facilities of telephone companies who charge much higher fees for the use of their networks. 11