Blockchain technology revolutionizes the Internet of Things (IoT) in different aspects. The IoT is an emerging technology that promotes daily human activities as very smart by enabling internet-based connection among intelligent devices. However, security is a significant barrier to the smooth and successful deployment of IoT in many fields. Security risks associated with the IoT environment are as follows.
   •  Data Gathering risks
   •  Data Transmission risks
   •  Tag being embedded risks
   •  Authentication and access control risks
   •  IoT infrastructure risks
  The IoT accomplishes better security standards by exploiting the unique nature of peer-to-peer decentralization, transparency, and data irreversibility. Blockchain technology assures IoT security with the assistance of consensus algorithms. It enables trust-free security services in between the resource-restricted IoT devices. The integration of blockchain into IoT offers many benefits:
   •  Trust-free security services
   •  Rectifies the reliability issues while maintaining the security
   •  The minimum cost of equipment
   •  Enhance the performance of the entire IoT
   •  Extend the life cycle of IoT products and services
  Blockchain-based IoT security is categorized into two main categories that are structural and functional. The structural security models are divided into sensor layer, network layer, application layer, surveillance of IoT devices, and province. The functional models protect the safety and privacy of IoT devices, access control, identity management, data assurance, self-regulation of IoT networks, and anti-distributed denial of service attacks.

Research Topics:

 •  Issues of integrating blockchain for IoT security
 •  Access control in IoT using blockchain technology
 •  Self-regulated IoT networks and management with blockchain
 •  Securing and managing the lifecycle of IoT devices using blockchain