Authorization or access control limits the actions a user may perform on a computer system, based on predetermined access control policies, thus preventing access by illegitimate actors. Access control for the Internet of Things (IoT) should be tailored to take inherent IoT network scale and device resource constraints into consideration. However, common authorization systems in IoT employ conventional schemes, which suffer from overheads and centralization. Recent research trends suggest that blockchain has the potential to tackle the issues of access control in IoT. However, proposed solutions overlook the importance of building dynamic and flexible access control mechanisms. In this paper, we design a decentralized attribute-based access control mechanism with an auxiliary Trust and Reputation System (TRS) for IoT authorization. Our system progressively quantifies the trust and reputation scores of each node in the network and incorporates the scores into the access control mechanism to achieve dynamic and flexible access control. We design our system to run on a public blockchain, but we separate the storage of sensitive information, such as user’s attributes, to private sidechains for privacy preservation. We implement our solution in a public Rinkeby Ethereum test-network interconnected with a lab-scale testbed. Our evaluations consider various performance metrics to highlight the applicability of our solution for IoT contexts.

中文翻译：

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物联网基于信任的区块链授权

授权或访问控制根据预先确定的访问控制策略限制用户可以在计算机系统上执行的操作，从而防止非法行为者访问。应定制物联网 (IoT) 的访问控制，以考虑固有的物联网网络规模和设备资源限制。然而，物联网中的常见授权系统采用传统方案，存在开销和集中化的问题。最近的研究趋势表明，区块链有可能解决物联网中的访问控制问题。然而，提议的解决方案忽略了构建动态和灵活的访问控制机制的重要性。在本文中，我们设计了一种去中心化的基于属性的访问控制机制，并带有辅助信任和声誉系统 (TRS) 用于物联网授权。我们的系统逐步量化网络中每个节点的信任和声誉分数，并将分数纳入访问控制机制中，以实现动态灵活的访问控制。我们将系统设计为在公共区块链上运行，但我们将敏感信息（例如用户属性）的存储分离到私有侧链以保护隐私。我们在与实验室规模测试台互连的公共 Rinkeby 以太坊测试网络中实施我们的解决方案。我们的评估考虑了各种性能指标，以突出我们的解决方案在物联网环境中的适用性。但我们将敏感信息（例如用户属性）的存储分离到私有侧链以保护隐私。我们在与实验室规模测试台互连的公共 Rinkeby 以太坊测试网络中实施我们的解决方案。我们的评估考虑了各种性能指标，以突出我们的解决方案在物联网环境中的适用性。但我们将敏感信息（例如用户属性）的存储分离到私有侧链以保护隐私。我们在与实验室规模测试台互连的公共 Rinkeby 以太坊测试网络中实施我们的解决方案。我们的评估考虑了各种性能指标，以突出我们的解决方案在物联网环境中的适用性。