Traffic Management Center --> ITS Roadway Equipment:
signal control commands

Definition
Included In
Communication Solutions
Characteristics
Security

Definitions

signal control commands (Information Flow): Control of traffic signal controllers or field masters including clock synchronization.

Traffic Management Center (Source Physical Object): The 'Traffic Management Center' monitors and controls traffic and the road network. It represents centers that manage a broad range of transportation facilities including freeway systems, rural and suburban highway systems, and urban and suburban traffic control systems. It communicates with ITS Roadway Equipment and Connected Vehicle Roadside Equipment (RSE) to monitor and manage traffic flow and monitor the condition of the roadway, surrounding environmental conditions, and field equipment status. It manages traffic and transportation resources to support allied agencies in responding to, and recovering from, incidents ranging from minor traffic incidents through major disasters.

ITS Roadway Equipment (Destination Physical Object): 'ITS Roadway Equipment' represents the ITS equipment that is distributed on and along the roadway that monitors and controls traffic and monitors and manages the roadway. This physical object includes traffic detectors, environmental sensors, traffic signals, highway advisory radios, dynamic message signs, CCTV cameras and video image processing systems, grade crossing warning systems, and ramp metering systems. Lane management systems and barrier systems that control access to transportation infrastructure such as roadways, bridges and tunnels are also included. This object also provides environmental monitoring including sensors that measure road conditions, surface weather, and vehicle emissions. Work zone systems including work zone surveillance, traffic control, driver warning, and work crew safety systems are also included.

Included In

This Triple is in the following Service Packages:

This triple is associated with the following Functional Objects:

This Triple is described by the following Functional View Data Flows:

indicator_control_data_for_signal_control

This Triple has the following triple relationships:

Relationship	Source	Destination	Flow
Interactive	ITS Roadway Equipment	Traffic Management Center	signal control status

Communication Solutions

Solutions are sorted in ascending Gap Severity order. The Gap Severity is the parenthetical number at the end of the solution.

Selected Solution

EU: UTMC Data - UTMC

Solution Description

This solution is used within the E.U.. It combines standards associated with EU: UTMC Data with those for I-F: UTMC. The EU: UTMC Data standards include upper-layer standards required to implement center-to-field communications using the UTMC Framework. The I-F: UTMC standards include lower-layer standards that support secure center-to-field and field-to-field communications using simple network management protocol (SNMPv2). While SNMPv2 offers some security capabilities, implementations are strongly encouraged to use SNMPv3 to ensure adequate security.

ITS Application Entity UTMC TS004.006			Click gap icons for more info.
Mgmt IETF RFC 1907	Facilities UTMC TS003	Security IETF RFC 9147
	TransNet IETF RFC 768 IP Alternatives
	Access Internet Subnet Alternatives

Note that some layers might have alternatives, in which case all of the gap icons associated with every alternative may be shown on the diagram, but the solution severity calculations (and resulting ordering of solutions) includes only the issues associated with the default (i.e., best, least severe) alternative.

Characteristics

Characteristic	Value
Time Context	Recent
Spatial Context	Local
Acknowledgement	True
Cardinality	Unicast
Initiator	Source
Authenticable	True
Encrypt	True

Interoperability	Description
Local	In cases where an interface is normally encapsulated by a single stakeholder, interoperability is still desirable, but the motive is vendor independence and the efficiencies and choices that an open standards-based interface provides.

Security

Information Flow Security
	Confidentiality	Integrity	Availability
Rating	Moderate	High	Moderate
Basis	Control flows, even for seemingly innocent devices, should be kept confidential to minimize attack vectors. While an individual installation may not be particularly impacted by a cyberattack of its sensor network, another installation might be severely impacted, and different installations are likely to use similar methods, so compromising one leads to compromising all. DISC: NYC believes this to be LOW: "The result of this will be directly observable."	Invalid messages could lead to an unauthorized user gaining control of an intersection. This could also be used to bring traffic to a standstill, which could lead to a large financial impact on the community. DISC: NYC believes this to be MODERATE: The signal timing is critical to the intersection operation; incorrect signal timing can lead to significant congestion and unreliable operation; while unsafe operation is controlled by the cabinet monitoring system, attackers could "freeze" the signal or call a preemption. RES: This will vary depending on the application and implementation.	These messages are important to help with preemption and signal priority applications. Without them, these applications mayl not work. However, if these signals are not received, the ITS RE will continue to function using its default configuration. The TMC should have an acknowledgement of the receipt of a message. DISC: NYC blieves this to be LOW: TMC doesn't play an active role in this application, i.e. even if it is unavailable, it is unlikely to affect the outcome of this application one way or the other. RES: This will vary depending on the application and implementation.

Security Characteristics	Value
Authenticable	True
Encrypt	True

Traffic Management Center --> ITS Roadway Equipment:signal control commands