Summary

Relationship to Other Components

As shown in the figure below, ITS standards are mapped directly to interfaces. While not shown on the diagram standards have also been mapped when available to physical and functional objects so there could also be a line between the Inventory and Standards. Note that not all of the physical/functional objects or interfaces in the architecture have defined ITS standards but most do.

Regional ITS Architecture Components – Standards

Approach

Whether this is an update to an existing architecture or the development of a completely new architecture the approach for the architecture's standards involves making use of the latest information from ARC-IT to identify the appropriate and current standards and communications solutions for the selected inventory and interfaces. A discussion with the core stakeholders is also good to review the choices available and devise or update the strategy or plan for choosing, tailoring, and implementing standards-based solutions.

The next sections describe the different activities involved in each approach:

-         Updating ITS Standards

-         Defining ITS Standards

Updating ITS Standards  

Updating the standards selections for an existing architecture are straight-forward once the inventory, services and interfaces are complete.

The new or modified interfaces represent potential new standardization opportunities. In addition, the standards identified with the other unchanged interfaces will likely have been updated since the previous version of the architecture. In addition, it is useful to gather information from regional stakeholders about their current use of standards.

ITS Standards primarily address interfaces between ITS elements, so updating the identification of ITS standards depends upon the update of the definition of the Interfaces. There are some basics to know prior to updating the list of communications solutions and ITS Standards. In general, each information flow has up to three types of standards that are relevant: a message set standard, a data element standard, and communications protocol standards. These are combined into a data profile and a communications profile which are then combined to make up a communications solution.

In the area of communications protocols, there are various technology choices that a region can make. Making the best choices depends on multiple factors, including throughput (how much data must be transmitted or received on the interface), maturity of the technology, network topology (how the ITS systems are connected together), infrastructure (fiber optic lines, leased land lines, etc.), and communications services (broadcast, publish/subscribe, etc.), among others.

In addition to communications standards to apply to interfaces a number of standards have been developed pertaining to the devices themselves. In ARC-IT these standards have been mapped as appropriate to the physical and functional objects. When RAD-IT is used and outputs are generated these standards will be shown alongside the Inventory pages.

The representation of standards in ARC-IT has been revised significantly from earlier versions of the National ITS Architecture and now provides more complete profiles of the set of standards applicable to different interfaces.

As described in the RAD-IT Tab for Standards, there are two primary ways standards are represented in regional ITS architectures:

-         Overall list of standards for the region

-         Standards applicable to particular information flows between elements.

The overall list of standards is an output that can be created from RAD-IT and is commonly found in a section on standards in a document describing the architecture. The standards related to specific information flows cannot be edited in RAD-IT, but the information flow to standards mapping is available in tabular, document, and website outputs.

During the update process, consider creating a regional standards strategy or plan, if the original architecture does not include it (or updating any existing strategies or plans). This document shows how the region will migrate toward ITS standards. As part of that effort, stakeholders could reach consensus on an approach for ITS standards applicable to the region's interfaces. In addition, consider adding a discussion of the process for specifying standards for application in specific projects.

In determining when and how to incorporate ITS standards for a given interface, it's critical to understand the relative maturity of the standards. For each potential standard, consider asking:

-         Has the ITS standard been approved or published by the Standards Development Organizations (SDOs)?

-         Has the ITS standard been adopted by multiple vendors or system integrators?

-         Has the ITS standard been tested, either informally by the vendor, or through the formal ITS Standards Testing Program funded by FHWA?

-         Is there an amendment to the ITS standard or is a new version currently in the works, and if so, how much of the standard will change as a result?

Developing ITS Standards for the Architecture

For a new architecture there are some additional steps to consider when it comes time to identify the device and communications standards for the deployments of ITS in the region that are defined in the architecture. As with updating standards for an existing architecture this process comes after the inventory, services, and interfaces have been defined and agreed upon by the stakeholders.

Engage and Educate Stakeholders

The identification of ITS standards for a region occurs later in the development process, once inventory, services, and interfaces have been identified, but it can be helpful when developing an ITS architecture for the first time, to provide education to the stakeholders early on regarding ITS Standards. This can be done via a presentation on standards as part of engaging stakeholders in the architecture development process. The presentation can address the importance of standards, especially with respect to cost, risk, and interoperability issues both within a region and when connecting to neighboring regions.

An extensive series of standards training modules is available from the ITS Professional Capacity Building (PCB) Program (https://www.pcb.its.dot.gov/stds_training.aspx), which has developed a wide array of traffic and transit related training modules covering most of the currently deployed ITS standards. Information about these standards can be found at the USDOT ITS website at http://www.standards.its.dot.gov/. Also included on this website are contact numbers, standards advisories, fact sheets, deployment lessons learned, peer-to-peer support, and outreach material as well as links to websites maintained by the various Standards Development Organizations (SDOs).

Identify standards for Region

The interfaces of the architecture provide a list of possible standards to consider. The details connecting interfaces to standards can be found on the ARC-IT website and in the RAD-IT database. In general, each information flow has up to three types of standards that are relevant: a message set standard, a data element standard, and communications protocol standards. These are combined into a data profile and a communications profile which are then combined to make up a communications solution.

In the area of communications protocols, there are various technology choices that a region can make. Making the best choices depends on multiple factors, including throughput (how much data must be transmitted or received on the interface), maturity of the technology, network topology (how the ITS systems are connected together), infrastructure (fiber optic lines, leased land lines, etc.), and communications services (broadcast, publish/subscribe, etc.), among others.

In addition to communications standards to apply to interfaces a number of standards have been developed pertaining to the devices themselves. In ARC-IT these standards have been mapped as appropriate to the physical and functional objects. When RAD-IT is used and outputs are generated these standards will be shown alongside the Inventory pages.

Decisions on technologies are generally not done while developing an architecture. They are usually done as part of ITS Strategic Plans, or when projects are deployed.

As part of this identification, review the standards currently used by the stakeholders. It's possible that many industry standards are already in use in the region. Encourage stakeholders to examine their existing interfaces and determine whether this is indeed the case. Discuss options for converting or translating these interfaces to make use of standards-based solutions over time.

Along with understanding ITS Standards and how they might apply to the region, consider also what others are doing. There may be decisions regarding certain standards made by a DOT that are to be applied across the entire state. Also, look at what neighboring jurisdictions and states may be doing. Working together and sharing resources will reduce risk for everyone and increase the integration between systems across the state and between states.

In addition to the interface standards that are being defined for ITS, a range of other regional standards may be considered that would facilitate interoperability and implementation of the regional ITS architecture. For example, standard base maps, naming conventions, measurement characteristics, georeferenced location standards, and organizational structure identifiers can all facilitate the meaningful exchange of information between systems in the region. These types of regional standards should also be considered and can be included in the standards documentation at the discretion of the region.

Regions may also want to consider creating a regional standards strategy or plan that shows how the region will migrate toward ITS standards. Documenting this strategy can help identify those standards currently deployed, those already planned for deployment, and identify issues that the region will need to address.

RAD-IT

ARC-IT maintains a mapping of information flows to ITS standards development activities. The Communications View pages of the ARC-IT website. Go to www.arc-it.net and select Architecture / Views / Communications. This includes the latest mapping between ARC-IT and the ITS communications standards. RAD-IT accesses this mapping information and makes it available for customization and tailored standards activity tables. The "Communications" tab in RAD-IT provides the opportunity to decide which of the communications solutions and ITS Standards activities best applies to the region. Use the Communications tab in RAD-IT to see the full list of standards are part of the architecture and use it when there are unique situations for your region, e.g. your state/region requires a certain standard interface for certain elements and you need to show that at the regional level.

Communications Tab in RAD-IT

RAD-IT provides an ITS Standards Report based on all of the information flows selected in the region. The report lists all standards associated with each architecture flow, either sorted by standard or by interface. Select the specific ITS standards that reflect the regional standards strategy. When using RAD-IT, try to minimize the number of user-defined information flows unique to the region. Since ITS Standards are created using ARC-IT as a framework, any user defined information flows in your architecture will not have these industry consensus-based communications solutions and ITS Standards identified for them.

When you are developing a project, export the project architecture information from RAD-IT into SET-IT and use SET-IT to build the physical view (e.g. customized service package diagram with elements and flows) and then use the Communications View to review the ARC-IT defined communications standards for each layer of the relevant communications profile. By Using SET-IT you will be able to see and customize the full interface protocols and standards associated with each communications layer on an interface.

Examples

Examples of Standards can be found in every regional ITS architecture either in tables in an architecture document or on the architecture websites. For those architectures that create a website based on the RAD-IT tool, the following standards information is provided (the example is from the Central Ohio Regional ITS Architecture). The first example is the summary of standards applicable to the architecture.

Standards Output Web Page Example

Selecting one of the standards identifies the flows to which this standard applies. The example below is a subset of the flows for the standard NTCIP 1203.

Interfaces per Standards Output Example