Publisher Copyright: © 2024 by SCITEPRESS – Science and Technology Publications, Lda.

The majority of mobile devices today are based on Arm architecture that supports the hosting of trusted applications in Trusted Execution Environment (TEE). RISC-V is a relatively new open-source instruction set architecture that was engineered to fit many uses. In one potential RISC-V usage scenario, mobile devices could be based on RISC-V hardware. We consider the implications of porting the mobile security stack on top of a RISC-V system on a chip, identify the gaps in the open-source Keystone framework for building custom TEEs, and propose a security architecture that, among other things, supports the GlobalPlatform TEE API specification for trusted applications. In addition to Keystone enclaves the architecture includes a Trusted Hart – a normal core that runs a trusted operating system and is dedicated for security functions, like control of the device’s keystore and the management of secure peripherals. The proposed security architecture for RISC-V platform is verified experimentally using the HiFive Unleashed RISC-V development board.

We investigate the problem of estimating the transmission time of fragmented messages over multiple disrupted links. We build a system model for the case where a single message is sent over a chain of links and the disruptions in these links are identically and independently distributed. For this case, we derive an approximation formula for the mean transmission time, based on number of links, length of fragments and distributions of disruptions. The formula is verified against simulation experiments in the cases of uniform and exponential distributions for disruptions.

A “best-effort” authentication method, which is easier to attack than generic authentication methods (but requires fewer computations for benign nodes), may be sufficient for certain networking scenarios. We illustrate this point by examining the case of fragment authentication by intermediaries in an opportunistic network. We describe mechanisms for implementing best-effort authentication, with the caveat that an authentication strength sufficient in one scenario may be unfit for another.

The increasing popularity and variety of consumer multimedia devices is driving the need for networked homes. Yet setting up a secure wireless network is a daunting task for most ordinary users. Recently, there have been several proposals for easing this process. However, none of the proposals consider the problem of how to make it easy to manage visitor access. In this paper, we motivate the requirements for visitor management, show the shortcomings of the current easy setup proposals in this regard, and propose a new setup procedure that makes it easy to manage visitor access to wireless networks. Our contributions are twofold: first we present an approach to assigning categories to client devices at admission time so that selective revocation of clients based on those categories becomes possible. Then we present the idea of admission tickets, a flexible and secure way to delegate conditional access rights. We report the results and experience of prototyping of the proposed procedure using the HostAP framework.