Mobile Trusted Computing Based on MTM

Trusted computing (TC) denotes a set of security-related hardware and software mechanisms that make a computing device work in a consistent manner, even in the presence of external attacks. For personal computers, TC typically is interpreted to be a software architecture designed around the trusted platform module (TPM), a hardware chip residing on the motherboard and implemented according to the specifications of the Trusted Computing Group (Trusted Computing Group, 2008A). In embedded devices, the state-of-the art in terms of hardware security and operating systems is significantly different from what is present on personal computers. So to stimulate the take-up of TCG technology on handsets as well, the recently approved mobile trusted module (MTM) specification (Trusted Computing Group, 2008B) defines new interfaces and adaptation options that match the requirements of the handset business ecosystem, as well as the hardware in use in the embedded domain. This chapter provides an overview of a few hardware security architectures (in handsets) to introduce the reader to the problem domain. The main focus of the text is in introducing the MTM specification – by first presenting its main functional concepts, and then by adapting it to one of the hardware architectures first described, essentially presenting a plausible practical deployment. The author also presents a brief security analysis of the MTM component, and a few novel ideas regarding how the (mobile) trusted module can be extended, and be made more versatile.