Secure Data Transmission in IoT Networks Using Blockchain and Lightweight Cryptography: Safeguarding the Connected Future

The number of connected devices that are part of the IoT has grown at a very fast pace and offered myriad advantages, but also created several problems in the spheres of data security and privacy. As more and more smart devices are being connected to each other, it has become imperative to provide a safe and reliable channel to communicate is essential to ward off ‘jammers' and hackers. This work aims to establish whether the combination of blockchain technology implementation and lightweight cryptographic algorithms can be used to improve security in IoT networks. One more benefit originates from the very nature of the block chain where every record is coded in blocks, this makes it possible to track records due to the decentralized nature of their database thus providing an efficient means of tracking data integrity and when it is being tempered with. Hence, it is easy to implement the proposed lightweight cryptographic algorithm so the IoT device will not have a problem in transmitting secure data as it possesses limited processing and energy capacity. Through the available literature, several methods of lightweight encryption including symmetric encryption and hash functions appropriate for IoT applications to ensure confidentiality and authentication are discussed. Besides, the paper considers how the implementation of smart contracts in blockchain enables providing security policies for automation that react to threats on time, preventing cyber attacks. These technologies in unison provide a strong defense mechanism against these issues which will make IoT more protected and secure for use. The scalability, efficiency and feasibility of the proposed solution has also been presented in this paper and thus the effectiveness of the presented solution has been explored to served as potential real world IoT systems.