Journal of Intelligent Systems and Internet of Things JISIoT 2690-6791 2769-786X 10.54216/JISIoT https://www.americaspg.com/journals/show/1581 2019 2019 Faculty of computers and informatics, Zagazig university, Egypt Ahmed Y. Abdullah Faculty of computers and informatics, Zagazig university, Egypt Ibrahim M. Elhenawy Faculty of computers and informatics, Zagazig university, Egypt Ahmed Abdelmonem The Internet of Things (IoT) is pervasive in today's world and may be located almost throughout. It is employed in smart cities for things like highways and clinics, as well as in smart buildings for things like regulating doors and air conditioner units, avoiding fires, and many other things. The Internet of Things (IoT) refers to a set of interconnected computing devices that may communicate with one another by exchanging data over the internet. This provides the opportunity for the attacker to penetrate the IoT technologies and get the important data they contain. The restricted measure performance of IoT systems is the source of the issue, as they make it impossible to implement the conventional security mechanism on these devices. As a result of this constraint, it is necessary to propose lightweight algorithms that are capable of supporting IoT devices. However, Internet of Things (IoT) safety and confidentiality are important challenges that might impede the technology's long-term growth. In this study, we have addressed the security of the internet of things from two primary vantage points, namely, IoT design and protocols. We cover the many levels that make up the architecture of the Internet of Things (IoT), as well as the security problems that are connected with those layers and the possible alternatives to those concerns. We went through a variety of protocols that are used in the layered evolution of the Internet of Things, as well as the security mechanisms that were built for every protocol 2022 2022 67 78 10.54216/JISIoT.060206 https://www.americaspg.com/articleinfo/18/show/1581