TUTORIALS

Blockchain-based smart contracts have been successfully growing, and their use cases are quite innovative and have attracted lots of interest. However, there is a fundamental limitation of decentralized applications—they execute in a closed environment and some bridge service (oracle) is needed when obtaining information outside of the blockchain. As decentralized applications evolve and mature, oracles play an increasingly prominent role in ensuring the safety across smart contracts. Despite the critical role that oracles play in blockchain industry, the understanding of their basic principles is still in its infancy, as it was demonstrated by numerous oracle attacks to smart contracts and also discussed in academia. This tutorial aims to provide systematic understanding of what is oracle in blockchain, types of oracles, how they function and most importantly, review various attack vectors and discuss solutions on how to mitigate them.

AYANA T. ASPEMBITOVA : Ayana T. Aspembitova is a Senior Research Analyst in Euler Labs - UK based blockchain company. She holds PhD degree in Physics from Nanyang Technological University, Singapore. Dr Aspembitova has spent over 6 years researching various problems in blockchain - from transaction analysis using tools from Physics and AI to developing models and methodologies for industry needs. Her work has been published in several peer-reviewed journals and presented at conferences. One of her recent accomplished projects was dedicated to the study of oracles in blockchain - she has developed a working methodology to mitigate oracle attacks for smart contracts in Ethereum and Cosmos blockchains that was published in Entropy journal.

Software Defined Networking (SDN), Blockchain (BC), and the Internet of Things (IoT) have emerged as synergistic domains, contributing significantly to security enhancement, network performance optimization, and overall improvement in the quality of life. The widespread adoption of IoT devices across various use cases and their pervasive availability have facilitated the integration of SDN and BC within this ecosystem, resulting in abundant opportunities for cutting-edge research endeavors. Our tutorial aims to present a comprehensive exploration of the integration of BC and SDN in the IoT landscape, which we refer to as BC-enabled Software-Defined IoT (BC-SDIoT). Initially, we delve into the motivations and drivers behind BC-SDIoT, meticulously examining its potential benefits and drawbacks. Subsequently, we classify pertinent research studies into six key implementation objectives and innovative concepts that synergistically blend BC and SDN to establish intelligent, secure, and efficient frameworks: Security, computing paradigms (edge and fog computing), trust management, access control & authentication, privacy, and networking. Within each corresponding section, we elucidate the categories, representing distinct problem domains, of this novel taxonomy, and provide an in-depth analysis of the related studies, presenting viable solutions. Furthermore, we address potential major challenges, open issues, and prospects that warrant extensive research attention, fostering the expansion of newer research domains within the realm of BC-SDIoT. Inclusive of our tutorial, we incorporate a software simulation, expertly designed to illustrate a fundamental vulnerability within SDN, effectively showcasing how an integrated BC implementation can mitigate such risks and bolster the overall security of the system. By the end of this tutorial, attendees will have gained valuable insights into the compelling convergence of SDN, BC, and IoT, enabling them to comprehend the intricacies and potential applications of BC-SDIoT in revolutionizing the landscape of networked systems. Through the dissemination of cutting-edge knowledge and research, we aim to inspire and encourage the pursuit of further advancements and innovations in this promising domain.

MURAT KARAKUS: Murat Karakus received a B.S. degree in Mathematics from Suleyman Demirel University, Turkey, in 2009, and the M.S. degree in Computer Science and Information Systems from the University of Michigan-Flint, USA, in 2013, and the Ph.D. degree in the Computer Science from Purdue School of Science in Indianapolis, USA, in 2018. He is currently working as an Assistant Professor at Ankara University in Turkey. He received the Best Paper Award at ACM SIGITE 2011 conference. He has 25+ peer-reviewed publications and is a reviewer for esteemed IEEE, ACM, and Elsevier journals and conferences. His research interests include next-generation network architectures, such as Software-Defined Networking (SDN), Blockchain technology, network scalability, Quality of Service (QoS), routing, economic analysis of network architectures and designs, and pricing network services.

EVRIM GULER: Evrim Guler received a Ph.D. in Computer Science from Georgia State University, Atlanta, GA in 2019. Currently, he is an Assistant Professor in the Department of Computer Engineering at Bartin University, Turkey, where he leads the Distance Education and Research Center. His research interests include Elastic Optical Networks, Software Defined Networking, Network Function Virtualization, Blockchain, routing, smart systems, and network modeling.

STEPHEN TURNER : Stephen Turner received the B.S degree in Computer Science and Applied Mathematics from Western Michigan University in 1987. Subsequently, he received the M.S degree in Computer Science in 1989, and the Ph.D. degree in Computer Science in 1989, both from Michigan State University, East Lansing, MI. He is currently an Associate Professor of Computer Science at the University of Michigan - Flint. He is the leader of a research cluster on Urban Sustainability and Environmental Health, and his research interests include security, Smart Grid, EV charging strategies for intelligent transportation systems, as well as better pedagogical approaches through next-generation digital learning environments.

SULEYMAN ULUDAG: Suleyman Uludag received his Ph.D. from DePaul University, Chicago in 2007. He is the director and a professor of computer science at the University of Michigan - Flint. The general areas of his research are cybersecurity, computer networks, and curriculum and program development. He was awarded the Lois Matz Rosen Junior Faculty Excellence in Teaching Award in September 2010 and the Research Award (Scholarly and Creative Activity) in April 2020 at the University of Michigan - Flint. He has also been a Fulbright Scholar (Core Program) at TOBB University of Economics and Technology in Ankara, Turkey, during the 2012-2013 academic year. He has been awarded another Fulbright Core Award to teach and research at the University of Sarajevo, Bosnia & Herzegovina for the 2018-19 academic year. He was a visiting scholar at the TCIPG (Trustworthy Cyber Infrastructure for the Power Grid) at the University of Illinois at Urbana-Champaign and the MONET research group of Professor Klara Nahrstedt at UIUC from August 2013 to August 2014. TCIPG is the preeminent research center on power grid cybersecurity. He has been an affiliated faculty at Michigan Institute for Data Science (MIDAS) at the University of Michigan, Ann Arbor. He has delivered twelve tutorials so far: IEEE ICCCN 2011, IMTIC 2012, IFIP NTMS 2014, IEEE CCNC 2015, NetSys 2015, ITC 27 2015, IIT 2015, IEEE NOMS 2016, IEEE ICC 2016, IEEE CCNC 2017, and CCNC 2018, CCNC 2019. He is also serving as a Commissioner and Team Chair for the ABET Computing Accreditation Commission.