Framework for cyber-physical systems: volume 2, working group reports
Edward Griffor, Chris L. Greer, David A. Wollman, Martin Burns · 2017
Sub-group 4, Timing and Synchronization -This sub-group evaluated timing and synchronization needs cyber-physical systems, including large-scale, distributed systems.This sub-group included an existing organization, Time Aware Applications, Computers and Communications Systems (TAACCS), also led by NIST.Topics addressed by the sub-group included fundamental timing concepts and time awareness in CPS, timing and latency, and the interactions between timing and security.Sub-group 5, Use Cases -This sub-group explored CPS use cases, both current and envisioned, in specific sectors, domains, and applications.Use cases provide a means for understanding how actors within CPS interact as well as inform functional requirements for the Framework.Manufacturing and food production use cases are provided as examples in Section 6 below. Organization of This DocumentBeyond the introductory material in this section, this Framework document is organized as follows:• Section 2: Report of the Cybersecurity and Privacy Sub-group: Trustworthiness • Section 3: Report of the Data Interoperability Sub-group • Section 4: Report of the Timing Sub-group • Section 5: Report of the Use Case Sub-group • Appendix A: References • Appendix B: Definitions and Acronyms • Department of Homeland Security, US Customs and Border Protection, Container Security Initiative (CSI) program [41] • Department of Homeland Security, US Customs and Border Protection, C-TPAT (Customs Trade Partnership Against Terrorism) program [43] • Department of Homeland Security, US Customs and Border Protection, Bonded Warehouse Manual for CBP Officers and Bonded Warehouse Proprietors [44] • Department of Homeland Security, US Customs and Border Protection, Amendment to the Current Reporting Requirements for the Ultimate Consignee at the Time of Entry or Release, [45] • Department of Homeland Security, US Customs and Border Protection, International Carrier Bonds for Non-Vessel Operating Common Carriers (NVOCCs) [46] 3.2.3.3Summary analysis Data-driven interactions between dependent and interdependent CPS require a precise unambiguous set of definitions to describe and regulate these interactions.Some of the needed definitions include roles of actors, control processes and procedures, and monitoring mechanisms.There may be an opportunity to describe and standardize these definitions to enable robust interactions between dependent and interdependent CPS.Assurance Possible via Enhancement PTP [77] nanoseconds No No Yes Yes NTP [76] milliseconds No No Yes Yes eLoran [115] nanoseconds No No Yes Yes WWVB [118] microseconds No No Yes Yes *Galileo is not yet a fully operational GNSS constellation, but has indicated strong support for source channel and data assurance via navigation message authentication.