As intelligent electronic systems pervade all aspects of our lives, capturing, storing, and communicating a wide range of sensitive and personal data, security is emerging as a critical concern that must be addressed in order to enable several current and future applications. Mobile appliances, which will play a critical role in enabling the visions of ubiquitous computing and communications, and ambient intelligence, are perhaps the most challenging to secure — they often rely on a public medium for (wireless) communications, are easily lost or stolen due to their small form factors and mobility, and are highly constrained in cost and size, as well as computing and battery resources.

This paper presents an introduction to security concerns in mobile appliances, and translates them into challenges that confront system architects, HW engineers, and SW developers, including how to bridge the processing and battery gaps, efficient tamper-proofing of devices, content protection, etc. Recent innovations and emerging commercial technologies that address these issues are also highlighted. We envision that, for a large class of embedded systems, security considerations will pervade all aspects of system design, driving innovations in system architecture, software, circuits, and design methodologies.