As we know, the utilization of Internet of Things ie. IoT devices continues to grow, substantial volumes of complex and sensitive data are produced and propagated via the internet. In spite of the widespread integration across diverse domains, IoT security poses a persistent obstacle necessitating further research. Authentication in IoT is crucial for establishing trust, yet conventional methods often employ costly cryptographic techniques unsuitable for resource-constrained IoT devices. Moreover, centralized authentication fails to address cross-domain authentication and scalability concerns. This paper presents a secure framework leveraging Blockchain-based authentication to tackle these issues. Additionally, we introduce CP-ABE for manage network accessibility. The suggested CP-ABE method involves four main steps: setup, key generation, encryption, decryption. In this system, access policies are generated based on attributes of IoT devices or users, and these policies are then recorded as transactions on a blockchain. Blockchain enabled network is responsible to maintain the secret keys of each attribute. After authentication, users/IoT devices must comply with access policies to access data. Evaluation against existing methods demonstrates superior performance of our proposed approach across various metrics.