CONSTRUCTING A 6LOWPAN HOME AREA NETWORK Ruben Edgardo Gonzalez B.S., California State University, Sacramento, 2000 PROJECT Submitted in partial satisfaction of the requirements for the degree of MASTER OF SCIENCE in COMPUTER ENGINEERING at CALIFORNIA STATE UNIVERSITY, SACRAMENTO FALL 2010 © 2010 Ruben Edgardo Gonzalez ALL RIGHTS RESERVED ii CONSTRUCTING A 6LOWPAN HOME AREA NETWORK A Project by Ruben Edgardo Gonzalez Approved by: __________________________________, Committee Chair Isaac Ghansah, Ph. D. __________________________________, Second Reader Nik Faroughi, Ph. D. ____________________________ Date iii Student: Ruben Edgardo Gonzalez I certify that this student has met the requirements for format contained in the University format manual, and that this project is suitable for shelving in the Library and credit is to be awarded for the Project. __________________________, Graduate Coordinator ________________ Suresh Vadhva Date Department of Computer Engineering iv Abstract of CONSTRUCTING A 6LOWPAN HOME AREA NETWORK by Ruben Edgardo Gonzalez In order to comply with future requirements related to the Smart Power Grid, wireless sensors will need to be embedded in household appliances. These appliances, through their embedded sensors, will communicate with the Utility Companies, as well as customers, and provide information related to energy consumption. In order to communicate this information, these sensors use radio signals that require special protocols in order to communicate with a central home gateway as well as a Utility Company’s Smart Meter. In this project the “IPv6 over 802.15.4” protocol, also called 6LowPAN, is used to construct a Wireless Sensor based Home Area Network. This is the same wireless technology that will be embedded in appliances in order to form a wireless sensor network. Because of the wireless nature of this type of network, they are susceptible to security threats; the topic of security is addressed. But how do you built a wireless sensor Home Area Network? What are the ingredients, in terms of technologies, needed to construct such a network? Are there any security issues that need to be addressed before implementing such a network? These questions are answered in this project. v Specific topics addressed include the radio signal protocol, the operating system needed to run in the target device as well as the host machine, the programming language needed to create applications that could run on the target device and the actual hardware used to host the operating system and run the applications. In addition, a chapter is dedicated to the discussion of security issues that this type of network is likely experience. The project culminates with the procedure employed to construct a small Home Area Network using the 6LowPAN protocol and related technologies. All of topics related to 6LowPAN have been documented on this report to help readers understand the key ideas needed to construct a home area network using open source tools and the 6LowPAN protocol. _____________________________________, Committee Chair Isaac Ghansah, Ph. D. _______________________ Date vi DEDICATION To Angela, because you have been the rock that keeps me grounded. By your example you teach me to be patient and never give up. vii ACKNOWLEDGEMENT Special thanks to Dr. Ghansah, for being so patient with me and guiding me through the different facets of the Master’s Program. Special thanks to Dr. Faroughi for being the second reader of this report and always responding to my questions and being such a helping hand. viii TABLE OF CONTENTS Page Dedication ......................................................................................................................... vii Acknowledgement ........................................................................................................... viii List Of Tables .................................................................................................................... xi List Of Figures .................................................................................................................. xii Chapter 1. INTRODUCTION .........................................................................................................1 1.1 Challenges for Wireless Embedded Devices in the Smart Home ............................1 1.2 Wireless Technologies Available ............................................................................3 1.3 Network Protocols That Work with 802.15.4 ..........................................................7 1.4 Using an IP Based Protocol for 802.15.4 .................................................................9 1.5 Software, Programming Tools and Wireless Devices ..........................................10 1.6 Project Outline ......................................................................................................10 2. THE 802.15.4 AND 6LowPAN STANDARDS ..........................................................12 2.1 Introduction to the IEEE 802.15.4 Standard ..........................................................12 2.2 6LowPAN Overview .............................................................................................23 3. HARDWARE AND SOFTWARE TECHNOLOGIES USED ...................................32 3.1 TinyOS and the nesC Programing Language .........................................................32 3.2 Hardware Architecture of TelosB Devices ............................................................40 4. WIRELESS SENSOR NETWORK SECURITY AND 6LowPAN ............................46 ix 4.1 Understanding Security Threats .............................................................................47 4.2 Smart Home Components and its Associated Security Issues ...............................51 4.3 Network Topology and Security, Beyond the IEEE 802.15.4 Standard ................57 4.4 The Need for Wireless Sensor Network Security Tools ........................................61 5. DESIGN, IMPLEMENTATION AND TESTING ......................................................63 5.1 Description of the Project ......................................................................................63 5.2 The Ingredients for the Project ..............................................................................63 5.3 Installing the Developers Environment .................................................................64 5.4 Detecting the TelosB Board and Loading Applications ........................................65 5.5 Running a 6LowPAN Based Tutorial ....................................................................68 5.6 Implementing the Experiment ................................................................................69 6. CONCLUSION ............................................................................................................88 Reference ...........................................................................................................................96 x LIST OF TABLES Page Table 1: Frequency Bands, Channelization and RF Parameters ....................................... 17 Table 2: Smart Meter Datasheet Stats ............................................................................... 51 Table 3: Message Integrity Code and Security Levels ..................................................... 53 xi LIST OF FIGURES Page Figure 1: Smart Grid Network ............................................................................................ 2 Figure 2: The OSI Model .................................................................................................. 15 Figure 3: The IEEE 802.15.4 Layer Architecture ............................................................. 16 Figure 4: Association Message Sequence Chart—Coordinator ........................................ 19 Figure 5: Active Scan Message Sequence Chart .............................................................. 20 Figure 6: 802.15.4 Data Frame ......................................................................................... 21 Figure 7: IP Protocol Stack vs 6LowPAN Stack .............................................................. 24 Figure 8: Addressing in a 6LowPAN Network ................................................................. 27 Figure 9: 802.15.4 Frames: Full and Minimal Addressing ............................................... 30 Figure 10: 6LowPAN Protocol Stack ............................................................................... 30 Figure 11: IPv6 Neighbor Discovery ................................................................................ 31 Figure 12: TinyOS Directory and Related Sub-Directories .............................................. 35 Figure 13: Typical Memory Layout of a Microcontroller ................................................ 37 Figure 14: A nesC application and its components .......................................................... 38 Figure 15: A nesC Component and Corresponding Code ................................................ 39 Figure 16: Memsic TelosB Mote TPR2420 ...................................................................... 42 Figure 17: TelosB Mote tpr2420 Block Diagram ............................................................. 43 Figure 18: Star Topology Representation ......................................................................... 58 Figure 19: Peer-to-Peer Topology Representation ........................................................... 59 xii Figure 20: Compilation of a TinyOS Application