Access control is recognized as one of the key elements in maintaining security and privacy within Internet of Things devices. By enforcing proper control mechanisms, the correct and secure use of system resources can be ensured. The IoT environment is characterized by three essential features: lightweight design, distribution, and dynamism. First, IoT devices, due to their limited computational and storage resources, are typically capable of performing only local operations such as minimal data storage. Therefore, implementing access control mechanisms on these devices imposes additional computational overhead. Second, the deployment of IoT devices is inherently distributed. Traditional access control methods are designed around a centralized trusted authority that stores all related information and makes access decisions based on it—an approach that can lead to issues such as processing delays, lack of synchronization, and the creation of single points of failure. Consequently, distributed access control solutions are required. In this study, a dynamic access control scheme is proposed. The design introduces optimizations aimed at reducing costs, simplifying complex cryptographic operations, ensuring timely revocation, enhancing access accuracy, enabling proper delegation of access across multiple domains, and preserving user confidentiality and privacy. System performance is improved through the use of a dynamic accumulator, which reduces communication rounds and accelerates access to authentication information. Additionally, two separate blockchain structures are employed concurrently—one dedicated to authentication and the other to integrity verification. The advantages of the proposed scheme include faster access to information, support for keyword-based search, dynamic access control, timely revocation of malicious entities, strong privacy preservation, reduced computational overhead, and fewer communication rounds. The only notable drawback is a slight increase in cost, which is negligible compared to the significant security benefits achieved.