SimplexTM in a Hostile Communications Environment : The Coordinated Prototype

vii 1 Problem Statement 1 2 A Prototype for Coordinated Control 3 3 Simplex Concepts 7 3.1 Dynamic Component Binding 8 3.1.1 Replacement Units 8 3.1.2 Fault Containment 9 3.2 Analytic Redundancy 10 3.2.1 Analytic Redundancy as Applied to Control 11 3.2.2 The Decision Module 12 3.2.3 Trusted and Untrusted Elements 13 3.2.4 Software Upgrade 13 3.2.5 Analytic Redundancy Compared to Other Methods 14 3.3 Rate-Monotonic Scheduling Theory 14 3.4 Simplex and COTS 15 3.5 The Benefits of Simplex 16 4 Prototype Design and Implementation 17 4.1 Technical Challenges 17 4.2 Hardware and Software Architecture 18 4.2.1 Real-time Device Control and Coordination 19 4.2.2 Computation and Communication Topology 20 4.2.3 Software Components 20 4.2.4 Communications Attack Modes 21 4.3 Prototype Implementation 22 4.3.1 Long Track Pendulums 23 4.3.2 Pendulum Coordination 24 4.3.3 Communications Support 24 4.3.3.1 Dtag Communications 24 4.3.3.2 Inter-node Communications 25