Access Control Models and Technologies for the Internet of Things

访问控制是计算机系统的一种安全特性，它确保只有在合法情况下才允许授权用户访问资源。Ross Anderson曾经说过，访问控制是“计算机安全的传统重心”。物联网（IoT）的出现，即嵌入在我们物理环境中的智能设备的互连网络，需要对如何实现访问控制进行重大重新思考。盲目地将物联网设备部署到我们的智能家居、车载网络和工业控制系统（ICS）中，而不适当地解决这些新出现的挑战，不仅会导致我们失去宝贵的数字资产，还会影响我们的人身安全。

Access Control is the security feature of a computer system that ensures access to resources is only granted to authorized users under legitimate circumstances. Ross Anderson once said that Access Control is the "traditional center of gravity of computer security.” The advent of the Internet of Things (IoT), namely, the inter-connected network of smart devices that are embedded in our physical environment, necessitates a significant rethinking of how Access Control is to be achieved. Mindlessly deploying IoT devices into our smart homes, vehicular networks, and industrial control systems (ICS) without properly addressing these emerging challenges will not only cause us loss of valuable digital assets, but also impact our physical safety. In this work, I will address three access control challenges in current IoT environments. The first challenge arises from the sheer scale of the massively distributed system composed of inter-connection of smart devices. How does one write down a properly formulated access control policy that accounts for the many devices and unanticipated access scenarios? Note that any errors in policy formulation could lead to the leakage of access to devices that affects our safety. With IoT becoming a global phenomenon, it is unrealistic to assume that all the users and devices are registered to a single Identity Management System. That assumption is as unreasonable as asking everyone in the world to have a Facebook or Google account (or to use the same Internet Service Provider). The second protection challenge is to support scenarios in which users (or their devices) who do not know one another want to share resources when they encounter one another in a casual and transient manner. The crux is to enable total strangers to establish trust of one another during chance encounters, without resorting to a global Identity Management System. The third protection challenge concerns the fact that smart devices are embedded in the physical world. Misuse is not simply about whether a single access has been granted to unauthorized parties, but about how, over time, the access pattern that emerge. The challenge is about the control of behavior pattern, as well as the pattern of collaboration among multiple devices. The objective of the proposed research program is to design, analyze, and develop novel Access Control models and technologies that address the aforementioned challenges.