VLSI Design and Test View of Computer Security
Shih‐Lien Lu · 2023
Computer security is becoming more and more important as more aspects of our life rely on information technology. The fundamental building block of information technology is semiconductor. Semiconductor enables Very Large-Scale Integrated (VLSI) Circuits which power the digital infrastructure. This presentation examines the challenges and opportunities of security from the point of view of VLSI design and technology. We first explain why security in general and hardware security in particular is challenging. We present a survey of different aspects of hardware security. We argue more work needs to be done in building the components to enhance hardware security. Moreover, we look at how design considerations of these components need to be different from regular design. As an example, we will take a deeper dive into Physically Unclonable Functions (PUF). PUF have been gaining attention since early 2000s and are now an established secure alternative to other key storage methods for many integrated circuits (ICs) such as FPGAs and microcontrollers. There are many works on the design of PUFs. However, the merits of a particular PUF should go beyond the normal Power-Performance-Area (PPA) of a standard digital integrated circuit. This is because the security primitive only occupies a very small portion of the whole chip. Improving a PUF design by some percentage makes little impact on the PPA of the whole chip. As a security primitive, it should be evaluated also on what its designated functionality as well. We summarize some of the evaluation criteria important for PUF. We also discuss some experience we had with challenges of SRAM based PUF.