Abstract
Security is becoming since several years a major issue in the domain of embedded systems. Fine grain reconfigurable architectures like FPGAs are providing many interesting features to be selected as an efficient target for embedded systems when security is an important concern. In this chapter we propose an overview of some existing attacks, a classification of attackers and the different levels of security as promoted by the FIPS 140-2 standard. We identify the main vulnerabilities of FPGAs to tackle the security requirements based on the security pyramid concept. We propose a presentation of some existing countermeasures at the different levels of the security pyramid to guarantee a defense-in-depth approach.