Multilevel design validation in a secure embedded system

We present a simulation-based methodology to support secure embedded design. The methodology is explained through a case study, the Thumbpod-2 portable embedded fingerprint authenticator. By using multilevel validation, we can observe the flow of sensitive information through the system as it takes on multiple forms, from software variables to hardware bus-signals. This allows shielding off of unwanted side-channel information leaks at the protocol, software, or hardware level. We discuss how the ThumbPod-2 design is partitioned into a side-channel-free implementation, and how a codesign environment called GEZEL is used to validate this partitioning process at each abstraction level.