ABSTRACT
The Internet-of-Things (IoT) is an emerging and evolving technology that connects the virtual and physical worlds. The interconnection of resource-constrained heterogeneous devices in the IoT through communication protocols enables them to exchange any data. Because of this massive data flow, the system is vulnerable to security attacks. The only way to protect data from security breaches is through encryption. Conventional cryptographic algorithms are unsuitable for IoT devices due to their lack of computing power, communication, energy efficiency, and memory capability. This leads to lightweight protocols, which should provide high security and performance at a low cost. This study investigates lightweight cryptographic protocols for resource-constrained devices commonly utilized in IoT applications. There are four types of lightweight cryptographic protocols: normal, ultra, hybrid, and multilevel lightweight algorithms. It also describes the different attacks and how lightweight protocols may protect against critical assaults. The chapter identifies some issues and challenges and suggests a lightweight cryptographic algorithm for data transfer at the IoT application layer.
