IJCSNS International Journal of Computer Science and Network Security, VOL.20 No.11, November 2020 131 Manuscript received November 5, 2020. Manuscript revised November 20, 2020. https://doi.org/10.22937/IJCSNS.2020.20.11.17 Towards Security Challenges to Internet-of-Things: Big Data, Networks, and Applications Shurug Alseady, Abdullah Baz, Tahani Alsubait, Louai Alarabi, Hosam Alhakami College of Computer and Information Systems, Umm Al-Qura University, Saudi Arabia Summary The recent era has witnessed a significant orientation towards investment and simulation of the real systems into smart systems that are based on using the Internet-of-Things. Internet-of-Things aims to interconnect distributed smart devices or sensors for simulating a specific domain system. Big data is considered to be a result of this connection. This research aims at discussing the importance of Internet-of- Things and examining the risks of simulating smart systems. Furthermore, the study also examines the architecture of smart Internet-of-Things (IoT) system and a structure layer of IoT risks by depicting a structure of Internet-of-Things challenges. The structure’s design is based on four layers that include: authorization, big data, security, and integrity. This paper extracts the risk impact level (from highest to lowest) of various smart applications. The study also shows a comparison between multiple smart applications of Internet-of-Things in various domains and the main challenges that are faced by them. A comparative study of previous research studies, presented in this league, reveals that the attacks and hacks are the highest risks for smart applications. After which, data integrity is the next issue of concern while using the smart applications. Keywords: Internet of Things; Security Challenges; Big Data; Networks. 1. Introduction In the era of digital technology, the implementation of real smart environment, more essentially, the Internet-of- Things (IoT) devices has become the subject of extensive research. It is very important to use the IoT applications in various domains to automate the controlling process of systems and facilitate decision making remotely. They can save lives, buildings, and other things in several situations. IoT will generate $14.4 trillion in net profit for enterprises over the next two decades. Organizations across all industries have started to develop and implement their own IoT strategies with the aim of seizing the opportunity that this new era presents. However, the usage of IoT comes with its own set of security challenges. The recent studies done in this domain present several solutions for the challenges in Internet-of-Things (IoT) and suggest means to improve decision making for the real applications [1, 2]. By 2020, the expected communicated sensors through the Internet for smart domain are going to reach thirty billion sensors. According to the latest statistics, the number of sensors will increase to seventy-five billion in 2025 (as shown in figure 1) [3]. It is evident that there has been acceleration in the use of technology and modern methods for securing data and network connection. Figure 1: A Recent Statistics of Usage Percentage of IoT Sensors and Devices [3] More specifically, IoT provides the connection between many devices via Internet [4]. Big data, which is gathered from multiple sources, is a powerful improvement in business investment and systems simulation. The massive volume of extracted sensory data that is obtained from the sensors or IoT devices shows a main obstacle challenge for the applications based on IoT solution. Prior motivations present solutions for Big Data that include analyzing data, classification, clustering, or prediction. Smart home, smart parking, smart city, smart farming, smart government, smart energy, and smart transportation are examples of IoT domains [5, 6, 7, 8, 9, 10]. IoT aims to interconnect distributed smart devices or sensors for simulating a specific domain system. Any IoT architecture system needs automation, good connection, 0 50 100 2015 2017 2019 2021 2023 2025 15.41 17.68 20.35 23.14 26.66 30.73 35.82 42.62 51.11 62.12 75.44 No. Sensors by billions