In Section 2, we make the assumptions of the AEGIS design explicit. Section 3 is the core of the paper, giving an overview of the AEGIS design, and then plunging into details of the IBM PC boot process and its modifications to support AEGIS. A model and logical dependencies for integrity chaining are given in Section 4, and a calculation of the complete bootstrap performance is given; performance is surprisingly good. Section 5 discusses related work and critically examines some alternative approaches to those taken in AEGIS. We discuss the system status and our next steps in Section 6, and conclude the paper with Section 7.