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UNLV Theses, Dissertations, Professional Papers, and Capstones 12-1-2013 Application of NTRU Cryptographic Algorithm for securing SCADA communication Amritha Puliadi Premnath University of Nevada, Las Vegas Follow this and additional works at: https://digitalscholarship.unlv.edu/thesesdissertations Part of the Information Security Commons, and the Theory and Algorithms Commons Repository Citation Puliadi Premnath, Amritha, "Application of NTRU Cryptographic Algorithm for securing SCADA communication" (2013). UNLV Theses, Dissertations, Professional Papers, and Capstones. 2018. http://dx.doi.org/10.34917/5363933 This Thesis is protected by copyright and/or related rights. It has been brought to you by Digital Scholarship@UNLV with permission from the rights-holder(s). You are free to use this Thesis in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s) directly, unless additional rights are indicated by a Creative Commons license in the record and/ or on the work itself. This Thesis has been accepted for inclusion in UNLV Theses, Dissertations, Professional Papers, and Capstones by an authorized administrator of Digital Scholarship@UNLV. For more information, please contact [email protected]. APPLICATION OF NTRU CRYPTOGRAPHIC ALGORITHM FOR SECURING SCADA COMMUNICATION By Amritha Puliadi Premnath Bachelor of Engineering, Computer Science Thiagarajar College of Engineering, India 2010 A thesis submitted in partial fulfillment of the requirements for the Master of Science - Computer Science School of Computer Science Howard R. Hughes College of Engineering The Graduate College University of Nevada, Las Vegas December 2013 © Amritha Puliadi Premnath, 2013 All Rights Reserved THE GRADUATE COLLEGE We recommend the thesis prepared under our supervision by Amritha Puliadi Premnath entitled Application of NTRU Cryptographic Algorithm for Securing SCADA Communication is approved in partial fulfillment of the requirements for the degree of Master of Science in Computer Science Department of Computer Science Ju-Yeon Jo, Ph.D., Committee Chair Yoohwan Kim, Ph.D., Committee Member Laxmi Gewali, Ph.D., Committee Member Venkatesan Muthukumar, Ph.D., Graduate College Representative Kathryn Hausbeck Korgan, Ph.D., Interim Dean of the Graduate College December 2013 ii ABSTRACT Application of NTRU Cryptographic Algorithm for securing SCADA Communication by Amritha Puliadi Premnath Dr. Ju-Yeon Jo, Examination Committee Chair Associate Professor of Computer Science University of Nevada, Las Vegas Supervisory Control and Data Acquisition (SCADA) system is a control system which is widely used in Critical Infrastructure System to monitor and control industrial processes autonomously. Most of the SCADA communication protocols are vulnerable to various types of cyber-related attacks. The currently used security standards for SCADA communication specify the use of asymmetric cryptographic algorithms like RSA or ECC for securing SCADA communications. There are certain performance issues with cryptographic solutions of these specifications when applied to SCADA system with real-time constraints and hardware limitations. To overcome this issue, in this thesis we propose the use of a faster and light-weighted NTRU cryptographic algorithm for authentication and data integrity in securing SCADA communication. Experimental research conducted on ARMv6 based Raspberry Pi and Intel Core machine shows that cryptographic operations of NTRU is two to thirty five times faster than the corresponding RSA or ECC. Usage of NTRU algorithm reduces computation and memory overhead significantly making it suitable for SCADA systems with real-time constraints and hardware limitations. iii ACKNOWLEDGEMENTS I would like to express my sincere gratitude to my committee chair, Dr. Ju-Yeon Jo for her strong support and guidance throughout my thesis. It gives me great pleasure in acknowledging her valuable assistance. I am extremely grateful to Dr.Yoohwan Kim for his indispensable advice, information, and valuable guidance on different aspects of my research work. I would like to thank my husband, Karthikkumar for his continuous support and motivation. His valuable thoughts and immense cooperation was imperative to my completion of this degree. I owe thanks to my family and friends for their immense love and encouragement. I would also like to thank Dr.Laxmi Gewali and Dr. Venkatesan Muthukumar for being a part of my committee. I convey my special thanks to the graduate coordinator, Dr. Ajoy K. Datta for all his support and advocacy. I extend my gratitude to the Student Affairs Maintenance department for funding my Master’s degree. iv TABLE OF CONTENTS ABSTRACT .............................................................................................................. iii ACKNOWLEDGEMENTS .................................................................................... iv TABLE OF CONTENTS .......................................................................................... v LIST OF TABLES ................................................................................................. viii LIST OF FIGURES ................................................................................................. ix CHAPTER 1 INTRODUCTION .............................................................................. 1 1.1 Need for Current Work ..................................................................................... 2 1.2 Outline............................................................................................................... 4 CHAPTER 2 BACKGROUND ................................................................................. 5 2.1 SCADA Architecture ........................................................................................ 5 2.1.1 Advantages of using Internet-based SCADA Architecture ..................... 8 2.2 SCADA Communication Standards and Trends ............................................... 8 2.2.1 SCADA Communication Protocols ......................................................... 9 2.2.1.1 Distributed Network Protocol (DNP3) ........................................... 9 2.2.1.2 IEC 61850 ..................................................................................... 11 2.2.1.3 IEC 60870-5 .................................................................................. 12 2.3 Overview of IEC 62351 .................................................................................. 12 CHAPTER 3 SECURITY CONSIDERATIONS FOR SCADA COMMUNICATION ............................................................................................... 14 3.1 Need for securing SCADA Communication .................................................. 14 3.1.1 Risk Factors associated with SCADA Architecture ............................. 15 3.2 Attacks in SCADA Communication-Classification ....................................... 17 3.3 Attack simulated in Power System ................................................................ 19 3.3.1 Terminology in Power System.............................................................. 19 3.3.2 Simulation ............................................................................................. 20 v CHAPTER 4 CRYPTOGRAPHIC SOLUTIONS IN SCADA SECURITY ...... 24 4.1 Role of Cryptography in SCADA security ..................................................... 24 4.1.1 Terminology ........................................................................................... 24 4.2 Role of Asymmetric Cryptography in SCADA Communication Protocols ... 27 4.2.1 In Encryption and Decryption ................................................................ 27 4.2.2 In Authentication ................................................................................... 27 4.3 Challenges in implementing Cryptographic solutions for SCADA security .. 28 4.3.1 Performance Issues while implementing IEC 62351 ............................. 29 CHAPTER 5 INTRODUCTION TO NTRU CRYPTOGRAPHIC ALGORITHM AND PROPOSED WORK ........................................................... 32 5.1 Introduction to NTRU ..................................................................................... 32 5.2 NTRU Public Key Cryptosystem.................................................................... 33 5.2.1 NTRU Parameters .................................................................................. 33 5.2.2 Key Generation ...................................................................................... 34 5.2.3 Encryption .............................................................................................. 35 5.2.4 Decryption.............................................................................................. 35 5.2.5 Example ................................................................................................. 36 5.2.6 Theoretical Operating Specifications ..................................................... 37 5.3 NTRU Signature Scheme ................................................................................ 38 5.4 Advantages of NTRU over other PKCS ......................................................... 39 5.5 Proposed Work................................................................................................ 39 5.5.1 Issue and Previous Approaches ............................................................. 39 5.5.2 Proposed Approach ...............................................................................
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