Architecture

A framework within which a system can be built. Requirements dictate what functionality the architecture must satisfy. An architecture functionally defines what the pieces of the system are and the information that is exchanged between them. An architecture is functionally oriented and not technology-specific which allows the architecture to remain effective over time. It defines "what must be done", not "how it will be done'.

Architecture Flow

Information that is exchanged between ITS entities in the physical architecture view of the U. S. National ITS Architecture V7.0. Architecture flows are the primary tool that is used to define the New York City Sub-Regional ITS Architecture interfaces. The terms "information flow" and "architecture flow" are used interchangeably.

Element

ITS elements are specific instances of either stakeholder centers, or stakeholder field equipment, or stakeholder vehicles with ITS equipment, or traveler equipment. ITS elements have customized functional requirements and customized interface requirements that are based on the stakeholder needs.

Information Flow

See Architecture Flow.

Intelligent Transportation System

The system defined as the electronics, communications or information processing used singly or integrated to improve the safety and efficiency of surface transportation.

Inventory

See System Inventory.

ITS Architecture

Defines the functional dependencies between stakeholder ITS elements that work together to deliver transportation services. An ITS architecture defines how stakeholder ITS elements functionally operate and the interconnection of information exchanges that must take place between these systems to accomplish transportation services. An ITS Architecture can be the technical foundation for institutional agreements between stakeholders to share in the deployment of future ITS services.

Logical Architecture

The logical architecture is represented by the set of functional requirements that implement services to meet user needs.

Physical Architecture

The physical architecture is derived from the part of the US National ITS Architecture V7.0 that provides stakeholder ITS elements with a physical representation (though not a detailed design) and the ITS interfaces to other ITS elements necessary to implement ITS services. The ITS elements and the architecture flows between them are the components of the physical architecture. ITS elements have ITS functions allocated to them. Each function has information inputs and one or more information outputs. Where the inputs of a function allocated to one ITS element have a dependency on an output from another ITS element, this functional dependency is represented by an architecture flow between the physical ITS elements in the New York City Sub-Regional ITS Architecture. These architecture flows and their communication requirements define the interfaces required between ITS elements, which are encoded using open standards (where available) that are used in other stakeholder ITS architectures worldwide.

Service Package

The service packages provide an accessible, service-oriented perspective to the New York City Sub-Regional ITS Architecture. They are tailored to fit, separately or in combination, real world transportation needs for New York City. Service packages collect stakeholder ITS elements that must work together to deliver a given transportation service and the architecture flows that connect them and other important external ITS elements.

Stakeholders

A widely used term that notates a public agency, private organization or the travelling public with a vested interest, or a "stake" in one or more transportation elements within the New York City Sub-Regional ITS Architecture.

Standards

Documented technical specifications sponsored by a Standards Development Organization (SDO) to be used consistently as rules, guidelines, or definitions of characteristics for the interchange of data.

System

A collection of hardware, software, data, processes, and people that work together to achieve a common goal. Note the scope of a "system" depends on one's viewpoint. To a sign manufacturer, a dynamic message sign is a "system". To NYSDOT, NYCDOT, MTA, or PANYNJ, the same sign may be only a component of a larger Freeway Management "System". In the New York City Sub-Regional ITS Architecture, a Freeway Management System is a part of the overall surface transportation intelligent transportation "system" for the New York City.

System Inventory

The collection of all ITS-related elements in the New York City Sub-Regional ITS Architecture.

U. S. National ITS Architecture

A common, established framework for developing regional integrated transportation system architectures. This framework was developed and continues to be maintained by an open consensus driven process with the participation of a diverse set of ITS stakeholders in the US. The US National ITS Architecture V7.0 is comprised of related logical and physical architecture components, which together satisfy a broad and defined set of legacy and future user service requirements. The US National ITS Architecture's allocation of functional requirements to physical ITS entities and the resultant functional dependencies between ITS entities have been adopted by standards development organizations as the foundation for many open ITS standards, and adopted by many ITS equipment manufacturers and their customers worldwide. The US National ITS Architecture is maintained and periodically updated by the United States Department of Transportation (USDOT).

User Needs

User Needs document what ITS should do from the stakeholder's perspective. A broad range of stakeholders were considered, including the travelling public as well as many different types of system developers, operators, maintainers and stakeholders with a dependency on the surface transportation system in New York City. User needs form the basis for the New York City Sub-Regional ITS Architecture development effort. The initial user needs were defined by stakeholders during interviews.