1. High-productivity development environments for certifiably dependable systems Dr. Darren Cofer Staff Scientist Honeywell Laboratories Minneapolis MN darren.cofer@honeywell.com 612-951-7279 NITRD / HCSS National Workshop on Aviation Software Systems: Design for Certifiably Dependable Systems

2. 2 File Number The problem with software… [-1] software = time * money [-2] time = money [-3] money = SQRT(evil) |–––––––––––– [ 1] software = evil

3. 3 File Number Is it really evil? Imagine building the mechanical components of an aircraft today without structural & aerodynamic analyses - “We’ll just build it and see if it flies.” - no consistent design discipline to support the level of system complexity currently implemented in software - CS grads trained as programmers but doing systems engineering All software-related failures are due to design errors - doesn’t break or wear out - testing and HW fault-models inadequate Software is too easy to change - susceptible to new errors at all life-cycle stages Software errors are logical errors - obscured by representation - difficult to detect errors by inspection

4. 4 File Number 000101101010001001 100101110110000010111101011 101001111011101100111011111111 1010100111011001010001111101 11001000101011010111111000 10010010001010101001001011111 10101110100010111011100110101 110010101010101000111110111 1111010011010001001000011 000101010001001101010001 00010010010101110000111000 1100010100100100000011 1111011101011101 The solution… SOFTWARE ELIMINATION

5. 5 File Number Well not really… Literally: Use custom hardware where it makes sense - reusable soft cores, FPGA/ASIC, SoC technologies - multicore processors = true concurrency - translate data flow models to data flow HW (not seq’l SW) Figuratively: Emulate what’s good about hardware - well-defined and scoped languages with well-established semantics - well-defined and constrained interfaces - composability (with predictable results) - standard reusable components and subsystems (ex: OS, comm) - analyzable

6. 6 File Number www.honeywell.com