1 2 3 4 5 PRELIMINARY DISCUSSION DRAFT 6 Framework for Cyber-Physical Systems 7 Release 0.7 8 3/3/2015 5:27 PM 9 10 11 Cyber Physical Systems Public Working Group 12 13 14 15 16 Table of Contents 17 Table of Contents ............................................................................................................................ iii 18 Table of Figures ................................................................................................................................ v 19 Table of Tables ............................................................................................................................... vii 20 Disclaimer ...................................................................................................................................... viii 21 Executive Summary ......................................................................................................................... ix 22 1 Purpose and Scope................................................................................................................. 1 23 1.1 Overview and Background ............................................................................................... 1 24 1.2 Purpose............................................................................................................................. 2 25 1.3 Scope ................................................................................................................................ 3 26 1.4 Definitions ........................................................................................................................ 4 27 2 Reference Architecture [RA Subgroup] ............................................................................... 23 28 2.1 Overview ........................................................................................................................ 23 29 2.2 Derivation of the Framework ......................................................................................... 25 30 2.3 The Role of Use Cases in the Framework Development ................................................ 28 31 2.4 Related Standards and Activities.................................................................................... 29 32 2.5 Example -- Smart Traffic: an example to illustrate key architectural notions .............. 30 33 2.6 SUMMARY ......................................................................................................................... 31 34 3 Facets of the CPS Framework .............................................................................................. 33 35 3.1 System Facet [RA Subgroup] .......................................................................................... 33 36 3.2 Engineering Facet [RA Subgroup] .................................................................................. 41 37 3.3 Assurance Facet [TBD Subgroup] ................................................................................... 45 38 4 Aspects of the CPS Framework ............................................................................................ 46 39 4.1 Risk Aspect ..................................................................................................................... 46 40 4.2 Data Aspect [DI Subgroup] ............................................................................................. 66 41 4.3 Timing Aspect [Timing Subgroup] ................................................................................ 103 42 4.4 Performance Aspect [tbd] ............................................................................................ 128 43 4.5 Life Cycle Aspect [tbd] .................................................................................................. 128 44 4.6 Topology Aspect [tbd] .................................................................................................. 128 45 5 Use Case Analysis – Use Case Subgroup ............................................................................ 130 46 5.1 Background ................................................................................................................... 130 47 5.2 Analysis Method ........................................................................................................... 134 48 5.3 Supporting CPS Use Case Examples with Evaluation ................................................... 140 49 5.4 Black box use cases ...................................................................................................... 147 50 5.5 Current CPS Examples and Black Box Use Case ........................................................... 147 51 6 References ......................................................................................................................... 148 52 6.1 Reference Architecture ................................................................................................ 148 53 6.2 Security Viewpoint ....................................................................................................... 149 54 6.3 Data Integration Viewpoint .......................................................................................... 153 55 6.4 Timing Viewpoint ......................................................................................................... 158 56 6.5 Usage Viewpoint .......................................................................................................... 165 57 iv 58 Table of Figures 59 Figure 1: Simplified CPS conceptual domain model ....................................................................... 3 60 Figure 2: Sector map showing segmentation of M2M (machine-to-machine) market and 61 identifying 9 key service sectors, key applications groups, and examples of connected devices . 4 62 Figure 3: Analysis of CPS and derivation of Framework ............................................................... 26 63 Figure 4: CPS Framework Reference Architecture – Domains, Facets, Aspects ........................... 28 64 Figure 5: A CPS View: Systems of Systems .................................................................................... 35 65 Figure 6: CPS Functional Domains ................................................................................................ 36 66 Figure 7: Engineering Facet ........................................................................................................... 41 67 Figure 8 - Historically systems design occurred within disparate disciplines. The disciplines were 68 prioritized based on domain-specific (energy, manufacturing, transportation) requirements and 69 perspectives. ................................................................................................................................. 54 70 Figure 9. Cyber-Physical Systems Risk Disciplines ........................................................................ 60 71 Figure 10 - CPS Risk Analysis ......................................................................................................... 60 72 Figure 11: JDL Fusion Framework ................................................................................................. 71 73 Figure 12: Merger of Different Sources of Data ........................................................................... 74 74 Figure 13: Data Fusion Today........................................................................................................ 74 75 Figure 14: Simplified Topology of Networks for a Chemical Plant ............................................... 77 76 Figure 15: Continuous Refinement of Privacy Risk Management ................................................ 87 77 Figure 16: Double-blind Authentication Scheme.......................................................................... 88 78 Figure 17: Taxonomy of data ....................................................................................................... 98 79 Figure 18: On Time Marker ......................................................................................................... 105 80 Figure 19: Architecture of a CPS Node and Environment ........................................................... 111 81 Figure 20: Domains and Multiple Time-scales in Time-aware CPSs ........................................... 115 82 Figure 21: CPS Network Manager configuring a CPS ................................................................. 116 83 Figure 22: Time-Aware CPS Device Model .................................................................................. 118 84 Figure 23: Requirements Decomposition into Primitives ........................................................... 135 85 Figure 24: Example of Reference Architecture Model of "Manufacturing" System-of-Interest 140 86 87 Table of Tables 88 Table 1: Elements of Secure Timing ............................................................................................ 121 89 Table 2: Survey of Time Distribution Methods ........................................................................... 122 90 Table 3: Principal threat vectors in an unsecured time network ............................................... 125 91 Table 4: List of Stakeholders ....................................................................................................... 132 92 Table 5: Application Categories .................................................................................................. 133 93 Table 6: CPS Example Template .................................................................................................