The enormously growing population in urban areas and the impact it has on the urban environment escalates the need of sophisticated management approaches that acquire the latest advancements of ICT, IoT and AI to enhance every city offered service. A smart city is capable of monitoring the physical world in real time and gathering city and citizens related data, then processing and analyzing this data in order to control city facilities and influence the life of citizens. The emerging of such technologies in cities raises multiple security and privacy concerns and challenges at individual and community levels. Several attempts have been introduced to guarantee the security and privacy of sensed data. In this paper we examine the security and privacy of smart city applications, the challenges faced and the solutions proposed. We first introduce smart cities and we provide an overview of major security problems and current solutions in some categories of smart cities. We then investigate the security challenges related to both city infrastructure and data, and we propose a framework to overcome these challenges.

INTRODUCTION

Cities can be defined as complex and highly organized human settlements that have extensive servicing systems for housing, power and water supplement, transportation, sanitation, land use, utilities and communication. These systems are responsible for facilitating interaction between people, government, organizations and business owners. Historically, cities were inhabited by a small proportion of humanity overall. Statistics showed that about 30 percent of the world’s population lived in cites in 1950. However, half of the world’s population is said to live in cities nowadays where the number shot up to nearly 55 percent in 2016. By 2030, 60 percent of the world’s population is expected to live in cities[1]. The rapid growth in size of residents generates a wide range of challenges including air pollution, traffic congestion, waste-disposal problems, high energy consumption and high crime rate. These problems can be difficult to tackle if cities were not prepared nor properly managed to accept the incoming population. As cities grow in population, citizens’ demands and needs must be met in ways that carry less harm to the environment.

A. Definition of smart cities

A smart city is a sustainable and innovative city that uses Information and Communication Technology (ICT) along with other means to optimize the efficiency of urban services and the quality of life, while ensuring that it covers the necessities of present and future generations with respect to environmental, economic and social aspects [2]. Smart cities aim to reduce resource consumption and to increase communication between citizens and governments. They are equipped with basic infrastructure and networks of sensors to collect information regarding the operational status of the various systems and urban services for real time analysis by information processing systems so as to improve their management and performance. The developed systems and applications in smart cities are designed to connect all devices and services within a city in order to facilitate the interaction of city representatives with both community and city infrastructure and to monitor the changes in the city and the way it evolves. The integration of sensor networks and computer systems across city infrastructure will reveal their exact operational status through measuring the flow of vehicles and people, waste disposal and levels of consumption. Hence, smart cities are crucial to face urbanization challenges effectively and to achieve more efficient and sustainable cities that drive economic growth and improve the quality of life for urban citizens [3].