Correspondence Rules
Several correspondence rules guide the relationships between viewpoints. Generally speaking, elements in one view may be referenced in some fashion in at least one other view. Specific correspondence rules are:
- Physical Objects are defined with scope such that they are under the control of a single Enterprise Object. Enterprise Objects have defined roles with Physical Objects.
- Functional Objects provide functionality to Physical Objects, as defined by PSpecs.
- Information Flows are characterized by Communications Characteristics, which imply various communications protocol standards.
- Information Flows are further defined by Data Flows.
- Information Flow and Data Flow definitions suggest ITS Application Layer standards.
- Security characteristics characterize Information Flows and Physical Objects; these characteristics in turn suggest physical and cybersecurity standards.
- Information Flows are always accompanied by a provision agreement relationship. Such relationships are formal if both participants are centers or field equipment. They are nearly always informal if between two mobile objects. If between mobile and fixed, the relationship may be formal if personalized or individually targeted information is exchanged.
- Coordination relationships may imply Communications Characteristics:
- An expectation of guaranteed delivery drives non-repudiation of receipt.
- An expectation of information provision may drive regularity and periodicity.
- An expectation of personal information exchange drives a high confidentiality requirement.
- Physical object context may constrain Communications Characteristics:
- Information flows between two mobile objects (vehicle or personal) are always restricted to wireless media.
- Communications involving one mobile object and one fixed object involve wireless media, but may also include fixed media backhaul.
- Communications between two vehicles always use short range wireless communications.