1. Independent Test Capability (ITC) ITC Synchronous Bus (ITCSB) 1553 and SpaceWire Interception Justin Morris Steven Seeger Brandon Bailey Scott Zemerick Mark Pitts Jeff Joltes Justin McCarty Dan Nawrocki Gary Carvell Peter Medley ITC Team Members Contact Us: ivv-itc@lists.nasa.govivv-itc@lists.nasa.gov Internal Website: http://itc.ivv.nasa.govhttp://itc.ivv.nasa.gov External Website: http://www.nasa.gov/centers/ivv/JSTAR/ITC.htmlhttp://www.nasa.gov/centers/ivv/JSTAR/ITC.html

2. Agenda ITCSB Description ITCSB Features ITCSB Interception Current Use – Demonstrations Conclusion NASA IV&V Facility Independent Test Capability 2

3. ITCSB Description Re-usable communication mechanism – Ensures consistent and correct data passing among distributed simulation components Provides synchronization between distributed applications Flexible and extensible design – Can be extended to incorporate any communication protocol NASA IV&V Facility Independent Test Capability 3

4. ITCSB Features Transport agnostic Cross platform C++ implementation Robust User API Specialized Layers: – MIL-STD-1553B – ESA SpaceWire – Time Sync Dynamic interception allows data manipulation – Without modification to software NASA IV&V Facility Independent Test Capability 4

5. ITCSB Interception Dynamically added and removed Priority-based Block, pass, and modify data – Fault injection – Bus monitoring Available utilities – 1553 Interceptor GUI – SpaceWire Interceptor GUI – Various command line utilities NASA IV&V Facility Independent Test Capability 5

6. Development & Interception ITCSB used to create simulation components – Useful for easy integration into simulation environment – Common libraries guarantee communication correctness Interception can come later – Development can occur without any consideration of interception – Dynamic nature of interception means it can be used later without modification to simulation component Interception is future-proofing – Any work can be done later without modification to code – Code can be augmented by insertion of interceptions on the network Development of interceptors separate from components NASA IV&V Facility Independent Test Capability 6

7. Data Flow With Interceptor Interceptor Modifying Data Interceptor Blocking Data ITCSB Interception NASA IV&V Facility Independent Test Capability 7 Node A Node B ITCSB Interceptor Normal Data Flow Modify Block

8. Current Use GPM Operational Simulator (GO-SIM) JWST IV&V Simulation and Test (JIST) Environment NASA IV&V Facility Independent Test Capability 8 ITCSB is the Main Communication Hub within GO-SIM and JIST

9. NASA IV&V Facility Independent Test Capability 9

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11. NASA IV&V Facility Independent Test Capability 11

12. Conclusion NASA IV&V Facility Independent Test Capability 12 ITCSB provides – Communications backbone for future simulation development – Synchronization for distributed simulation components Mitigates timing concerns – Interceptors that allow the changing of data without modification to software under test ITCSB interception is the most beneficial feature for the IV&V analysts – Provides mechanism for fault injection – Allows for testing scenarios that are often impossible with hardware