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21st Century Operations Using twenty-first Century Technologies

5.1 System Architecture Concept

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Currently, all agencies operate their systems in an isolated manner. None are electronically integrated. However, they do share a great deal of information via telephone, fax, or by viewing ARTIMIS information on public Internet sites.

A variety of agencies in the OKI region have determined that they can benefit from electronically integrating with ARTIMIS. In this way, they can share data and video images, and enable shared control of video cameras, Dynamic Message Signs (DMS) and Highway Advisory Radio (HAR). There are some agencies that do not believe they can derive benefits from this electronic integration, and others that want to share data but do not wish to share device control.

The system architecture concept that was developed serves this diversity of needs. Through a series of workshops, various system architecture conceptual models were presented for regional stakeholder review. Each model was developed to accomplish the objective of ensuring flexibility, and each has its various pros and cons. Based on the discussion, a system architecture called the Membership Model was selected. This model relies on the ARTIMIS system to:

  • Collect data from ARTIMIS' data gathering systems (as is currently accomplished).
  • Collect data sent from regional partners via phone, fax and/or electronic means (as is done with several partners today).
  • Automatically merge ARTIMIS and partner data to create a regional view of the multimodal transportation network.
  • Automatically disseminate the merged regional information to regional partners in a format suitable for public sector use.
  • Disseminate the merged regional information to the general public, in a format suitable for public use.
  • Serve as a regional communications portal to enable agencies to share control of other agencies' field devices. The agencies that own the field devices will be able to choose whether they wish to allow other agencies to use their field devices.

Under this system architecture concept, there will be three possible levels of participation (membership) in regional data sharing, as shown in Table 5-1.

Table 5-1 Membership Model System Architecture Concept Member Functions
Function Tier 1
Member 		Tier 2
Member 		Tier 3
Member
Joint operations, shared/tiered control of field devices X - This function is enabled under the Tier 1 membership empty cell empty cell
Regional video image access and sharing (input and receive) X - This function is enabled under the Tier 1 membership empty cell empty cell
Regional non-public data access and sharing (input and receive) X - This function is enabled under the Tier 1 membership X - This function is enabled under the Tier 2 membership empty cell
Regional non-public data and video image viewing only X - This function is enabled under the Tier 1 membership X - This function is enabled under the Tier 2 membership empty cell
Internet access - same as public information X - This function is enabled under the Tier 1 membership X - This function is enabled under the Tier 2 membership X - This function is enabled under the Tier 3 membership

X indicates that the function is enabled

Tier 1 Members will not only receive data from ARTIMIS, but will also provide data to ARTIMIS. This data exchange will improve interagency coordination for regional incident management. It will also enable ARTIMIS to create a richer congestion/operations database for the regional multi-modal system than the one existing today.

A large amount of the data to be exchanged between Tier 1 members and ARTIMIS is considered "non-public" data in its unfiltered form, and not currently accessible to the general public. However, it is useful for transportation operations. An example of this type of non-public data is detailed crash and other incident location and severity data that is input to computer-aided dispatch systems.

Tier 1 members will also have the option to operate each other's cameras, DMS and HAR, based on the owning agency's discretion. Several agencies have noted that they are not inclined to allow others to share control of DMS or HAR. These same agencies have indicated that they may allow access to pan/tilt/zoom controls for CCTV, but are not committed to the concept. Other agencies have fewer reservations with regard to sharing device control. The plan allows for adding shared control of specific devices over time.

The Membership Model enables shared control, which is known as shared and tiered control in the ITS community. This type of system has been implemented in Atlanta by the Georgia DOT (and at other locations such as Salt Lake City that use GDOT software), and in Phoenix, Arizona. Under shared and tiered control, the system and software are configured so that the agency that owns the devices has the capability to permanently or temporarily prevent individual or all other users from accessing device control. This is similar to the role of a computer network manager in an office environment. An agency can allow access to their devices with the confidence that they will be able to override other users at any time, or permanently lock out other users.

For example, Agency A can be zooming Agency B's camera to view an incident located on Agency B's roadway, which is adjacent to Agency A's roadway. If Agency B needs to use that same camera to focus on an incident on their own facility, they will have the capability to take over camera control from Agency A. Agency A will be considered a "secondary" user of the camera, since they do not own it. In practice, operators typically phone one another to explain why they took control of the camera and to determine if they can help each other gather information. A set of rules and protocols will need to be established that dictate which agencies can control whose devices and when this can be done.

Tier 2 Members will receive the full set of ARTIMIS data, including the unfiltered, non-public data. They are not required to transmit data (either because they have no data to send or are simply unwilling to do so), but will be able to transmit data to ARTIMIS if they wish. Tier 2 members will not have the capability to control other agency's devices.

Tier 3 Members will have the same access to ARTIMIS information as the public. They will be able to view information on the Internet, or choose not to view information. Because Tier 3 members are the same as the general public, they are no longer described in this document as a separate tier member. All references to public access to ARTIMIS data via the Internet apply to Tier 3 users.

Each agency will determine the membership level that best suits their needs. The concept of operations, described below, provides more detail on data flows between agencies, and shows how different types of agencies will operate under each membership level.

5.1.1 Funding and Institutional Implications of the Membership System Architecture Concept

The integrated system architecture of the Membership Model will require both capital and maintenance funding to deploy, operate, and maintain. Historically, State DOTs have taken on capital costs to deploy ITS systems and field devices, including integrating with partners. One reason for this is that these projects are ranked higher when multiple agency partners are involved, so the very existence of a partnership is considered the contribution from the partners. The Membership Model places the OKI region at the forefront of current FHWA policy encouraging integration between multiple partners. Various other funding sources can be made available. Because the ARTIMIS future system architecture integrates the emergency response community with the freeway management system, it may be eligible for funding from the Department of Justice (DOJ). The DOJ has indicated their readiness to fund these types of projects.

A majority of the regional agencies that participated in developing this Plan have agreed that sharing maintenance and operations costs between participating agencies is a reasonable expectation, since all will share in the system's benefits. Tier 1 members will logically have a larger cost burden than Tier 2 members. Tier 3 members can view public data at no cost, since this is already a free public service. All agencies felt that a reasonable one-time or annual cost can be assessed to defray maintenance and operations costs. They also agreed that sharing the funding of the system will increase the participating agencies' commitment to sharing data and operating together.

The system architecture concept also has institutional implications. Currently, all members of the various ARTIMIS committees have an equal voice in discussions regarding ARTIMIS policy and operations. In the future, a committee structure will need to be developed that recognizes the financial and operating partnership of the Tier 1 and Tier 2 members of ARTIMIS, which is distinct from the Tier 3 members.

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