TM18: Drawbridge Management
This service package supports systems that manage drawbridges at rivers and canals and other multimodal crossings (other than railroad grade crossings which are specifically covered by other service packages). The equipment managed by this service package includes control devices (e.g., gates, warning lights, dynamic message signs) at the drawbridge as well as the information systems that are used to keep travelers apprised of current and forecasted drawbridge status.
Relevant Regions: Australia, Canada, European Union, and United States
- Enterprise
- Functional
- Physical
- Goals and Objectives
- Needs and Requirements
- Sources
- Security
- Standards
- System Requirements
Enterprise
Development Stage Roles and Relationships
Installation Stage Roles and Relationships
Operations and Maintenance Stage Roles and Relationships
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Source | Destination | Role/Relationship |
---|---|---|
ITS Roadway Equipment Maintainer | ITS Roadway Equipment | Maintains |
ITS Roadway Equipment Manager | ITS Roadway Equipment | Manages |
ITS Roadway Equipment Owner | ITS Roadway Equipment Maintainer | System Maintenance Agreement |
ITS Roadway Equipment Owner | ITS Roadway Equipment Manager | Operations Agreement |
ITS Roadway Equipment Owner | Multimodal Crossing Equipment Owner | Information Exchange and Action Agreement |
ITS Roadway Equipment Owner | Traffic Management Center Owner | Information Exchange Agreement |
ITS Roadway Equipment Supplier | ITS Roadway Equipment Owner | Warranty |
Multimodal Crossing Equipment Maintainer | Multimodal Crossing Equipment | Maintains |
Multimodal Crossing Equipment Manager | Multimodal Crossing Equipment | Manages |
Multimodal Crossing Equipment Owner | ITS Roadway Equipment Owner | Information Exchange and Action Agreement |
Multimodal Crossing Equipment Owner | Multimodal Crossing Equipment Maintainer | System Maintenance Agreement |
Multimodal Crossing Equipment Owner | Multimodal Crossing Equipment Manager | Operations Agreement |
Multimodal Crossing Equipment Owner | Traffic Management Center Owner | Information Exchange Agreement |
Multimodal Crossing Equipment Supplier | Multimodal Crossing Equipment Owner | Warranty |
Traffic Management Center Maintainer | Traffic Management Center | Maintains |
Traffic Management Center Manager | Traffic Management Center | Manages |
Traffic Management Center Manager | Traffic Operations Personnel | System Usage Agreement |
Traffic Management Center Owner | ITS Roadway Equipment Owner | Information Exchange Agreement |
Traffic Management Center Owner | Multimodal Crossing Equipment Owner | Information Exchange Agreement |
Traffic Management Center Owner | Traffic Management Center Maintainer | System Maintenance Agreement |
Traffic Management Center Owner | Traffic Management Center Manager | Operations Agreement |
Traffic Management Center Owner | Transportation Information Center Owner | Information Provision Agreement |
Traffic Management Center Supplier | Traffic Management Center Owner | Warranty |
Traffic Operations Personnel | Traffic Management Center | Operates |
Transportation Information Center Maintainer | Transportation Information Center | Maintains |
Transportation Information Center Manager | Transportation Information Center | Manages |
Transportation Information Center Owner | Transportation Information Center Maintainer | System Maintenance Agreement |
Transportation Information Center Owner | Transportation Information Center Manager | Operations Agreement |
Transportation Information Center Supplier | Transportation Information Center Owner | Warranty |
Functional
This service package includes the following Functional View PSpecs:
Physical
The physical diagram can be viewed in SVG or PNG format and the current format is SVG.SVG Diagram
PNG Diagram
Includes Physical Objects:
Physical Object | Class | Description |
---|---|---|
Driver | Vehicle | The 'Driver' represents the person that operates a vehicle on the roadway. Included are operators of private, transit, commercial, and emergency vehicles where the interactions are not particular to the type of vehicle (e.g., interactions supporting vehicle safety applications). The Driver originates driver requests and receives driver information that reflects the interactions which might be useful to all drivers, regardless of vehicle classification. Information and interactions which are unique to drivers of a specific vehicle type (e.g., fleet interactions with transit, commercial, or emergency vehicle drivers) are covered by separate objects. |
ITS Roadway Equipment | Field | '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. |
Multimodal Crossing Equipment | Field | 'Multimodal Crossing Equipment' represents the control equipment that interfaces to a non-road based transportation system at an interference crossing with the roadway. The majority of these crossings are railroad grade crossings that are more specifically addressed by the "Wayside Equipment" terminator. This multimodal crossing terminator addresses similar interface requirements, but for other specialized intersections like draw bridges at rivers and canals. These crossings carry traffic that may take priority over the road traffic at the intersection. The data provided will in its basic form be a simple "stop road traffic" indication. However more complex data flows may be provided that give the time at which right-of-way will be required and the duration of that right-of-way requirement. |
Traffic Management Center | Center | 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. |
Traffic Operations Personnel | Center | 'Traffic Operations Personnel' represents the people that operate a traffic management center. These personnel interact with traffic control systems, traffic surveillance systems, incident management systems, work zone management systems, and travel demand management systems. They provide operator data and command inputs to direct system operations to varying degrees depending on the type of system and the deployment scenario. |
Transportation Information Center | Center | The 'Transportation Information Center' collects, processes, stores, and disseminates transportation information to system operators and the traveling public. The physical object can play several different roles in an integrated ITS. In one role, the TIC provides a data collection, fusing, and repackaging function, collecting information from transportation system operators and redistributing this information to other system operators in the region and other TICs. In this information redistribution role, the TIC provides a bridge between the various transportation systems that produce the information and the other TICs and their subscribers that use the information. The second role of a TIC is focused on delivery of traveler information to subscribers and the public at large. Information provided includes basic advisories, traffic and road conditions, transit schedule information, yellow pages information, ride matching information, and parking information. The TIC is commonly implemented as a website or a web-based application service, but it represents any traveler information distribution service. |
Includes Functional Objects:
Functional Object | Description | Physical Object |
---|---|---|
Roadway Multimodal Crossing Control | 'Roadway Multimodal Crossing Control' monitors multimodal crossings and monitors and controls traffic control equipment in the vicinity of the crossing. Equipment controlled includes warning lights, gates, dynamic message signs, and other systems associated with multimodal crossings. It manages draw bridges and miscellaneous other crossings between highway traffic and other modes. Railroad grade crossings are covered by other functional objects. | ITS Roadway Equipment |
TMC Multimodal Crossing Management | 'TMC Multimodal Crossing Management' remotely monitors and manages multimodal crossings, including draw bridges and other crossings between highway traffic and other modes. Equipment controlled includes warning lights, gates, dynamic message signs, and other systems that provide driver information and control traffic at multimodal crossings. Railroad grade crossings are covered by other functional objects. | Traffic Management Center |
Includes Information Flows:
Information Flow | Description |
---|---|
driver information | Regulatory, warning, guidance, and other information provided to the driver to support safe and efficient vehicle operation. |
highway control status | Current traffic control equipment status that indicates operational status and right-of-way availability to the non-highway transportation mode at a multimodal crossing. |
multimodal crossing inhibit | It contains commands that will inhibit the operation of a multi-modal crossing so that it will not stop or restrict the normal flow of road traffic. |
multimodal crossing status | Indication of operational status and pending requests for right-of-way from equipment supporting the non-highway mode at multimodal crossings. |
right-of-way request notification | Notice that a request has occurred for signal prioritization, signal preemption, pedestrian call, multi-modal crossing activation, or other source for right-of-way. |
road network conditions | Current and forecasted traffic information, road and weather conditions, and other road network status. Either raw data, processed data, or some combination of both may be provided by this flow. Information on diversions and alternate routes, closures, and special traffic restrictions (lane/shoulder use, weight restrictions, width restrictions, HOV requirements) in effect is included. |
roadway dynamic signage data | Information used to initialize, configure, and control dynamic message signs. This flow can provide message content and delivery attributes, local message store maintenance requests, control mode commands, status queries, and all other commands and associated parameters that support remote management of these devices. |
roadway dynamic signage status | Current operating status of dynamic message signs. |
signal control commands | Control of traffic signal controllers or field masters including clock synchronization. |
signal control status | Operational and status data of traffic signal control equipment including operating condition and current indications. |
signal fault data | Faults reported by traffic signal control equipment. |
traffic operator data | Presentation of traffic operations data to the operator including traffic conditions, current operating status of field equipment, maintenance activity status, incident status, video images, security alerts, emergency response plan updates and other information. This data keeps the operator appraised of current road network status, provides feedback to the operator as traffic control actions are implemented, provides transportation security inputs, and supports review of historical data and preparation for future traffic operations activities. |
traffic operator input | User input from traffic operations personnel including requests for information, configuration changes, commands to adjust current traffic control strategies (e.g., adjust signal timing plans, change DMS messages), and other traffic operations data entry. |
Goals and Objectives
Associated Planning Factors and Goals
Planning Factor | Goal |
---|---|
A. Support the economic vitality of the metropolitan area, especially by enabling global competitiveness, productivity, and efficiency; | Improve freight network |
D. Increase the accessibility and mobility of people and for freight; | Reduce congestion |
E. Protect and enhance the environment, promote energy conservation, improve the quality of life, and promote consistency between transportation improvements and State and local planned growth and economic development patterns; | Protect/Enhance the Environment |
G. Promote efficient system management and operation; | Improve efficiency |
Associated Objective Categories
Associated Objectives and Performance Measures
Needs and Requirements
Need | Functional Object | Requirement | ||
---|---|---|---|---|
01 | Traffic Operations need to be able to manage traffic control equipment at drawbridges at rivers, canals and other multimodal crossings. | Roadway Multimodal Crossing Control | 01 | The field element shall include sensors to monitor requests from non-highway traffic to cross at multimodal crossings for specified durations (such as draw bridges and miscellaneous other interference crossings between highway traffic and other modes such as river traffic, aircraft, etc.); the sensors are under center control. |
02 | The field element shall include signals to control traffic at multimodal crossings on surface streets, under center control. | |||
04 | The field element shall provide operational status for the sensors, signals, and driver information systems equipment at multimodal crossings to the center. | |||
05 | The field element shall provide fault data for the sensors, signals, and driver information systems equipment at multimodal crossings to the center for repair. | |||
06 | The field element shall forward all requests for right-of-way at multimodal crossings to the controlling center. | |||
TMC Multimodal Crossing Management | 01 | The center shall remotely control traffic signal controllers for use at major multimodal crossings. | ||
03 | The center shall collect operational status for the equipment at multimodal crossings. | |||
04 | The center shall collect fault data for the equipment at multimodal crossings for repair. | |||
02 | Traffic Operations need to be able to issue drawbridge crossing status information for drivers. | Roadway Multimodal Crossing Control | 03 | The field element shall include driver information systems (such as dynamic messages signs, highway advisory radios (HAR), and equipment that controls warning lights and gates) that advise drivers at multimodal crossings, under center control. |
TMC Multimodal Crossing Management | 02 | The center shall remotely control driver information systems (such as dynamic messages signs, highway advisory radios (HAR), and equipment that controls warning lights and gates) to notify drivers of closure durations and times at multimodal crossings. | ||
05 | The center shall distribute multimodal crossing information to other centers for dissemination to travelers. |
Security
In order to participate in this service package, each physical object should meet or exceed the following security levels.
Physical Object Security | ||||
---|---|---|---|---|
Physical Object | Confidentiality | Integrity | Availability | Security Class |
ITS Roadway Equipment | Moderate | High | Moderate | Class 3 |
Multimodal Crossing Equipment | Moderate | Moderate | Moderate | Class 2 |
Traffic Management Center | Moderate | High | Moderate | Class 3 |
Transportation Information Center | Low | Low | Moderate | Class 1 |
In order to participate in this service package, each information flow triple should meet or exceed the following security levels.
Information Flow Security | |||||
---|---|---|---|---|---|
Source | Destination | Information Flow | Confidentiality | Integrity | Availability |
Basis | Basis | Basis | |||
ITS Roadway Equipment | Driver | driver information | Not Applicable | High | Moderate |
This data is sent to all drivers and is also directly observable, by design. | This is the primary signal trusted by the driver to decide whether to go through the intersection and what speed to go through the intersection at; if it's wrong, accidents could happen. | If the lights are out you have to get a policeman to direct traffic – expensive and inefficient and may cause a cascading effect due to lack of coordination with other intersections. | |||
ITS Roadway Equipment | Multimodal Crossing Equipment | highway control status | Moderate | High | Moderate |
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. | Control flows, even for seemingly innocent devices, should have MODERATE integrity at minimum, just to guarantee that intended control messages are received. Incorrect, corrupted, intercepted and modified control messages can or will result in target field devices not behaving according to operator intent. The severity of this depends on the type of device, which is why some devices are set MODERATE and some HIGH. | Control flow availability is related to the criticality of being able to remotely control the device. For most devices, this is MODERATE. For purely passive devices with no incident relationship, this will be LOW. All devices should have default modes that enable them to operate without backhaul connectivity, so no device warrants a HIGH. | |||
ITS Roadway Equipment | Traffic Management Center | right-of-way request notification | Low | Moderate | Moderate |
This can be reasonably guessed based on observing the ITS RE's environment. It is obvious when a bus approaches an intersection. | Invalid messages could lead to an unauthorized user gaining signal priority at an intersection. This could also be used to delay traffic, which could lead to a financial impact on the community. However, the traffic signal will have controls in place to ensure that it does not display an illegal configuration (such as green in every direction). | Even if all of the Right-of-way Requests are not passed along from an ITS RE, the intersection will still operate as normal. There are other existing methods to assist a right-of-way requesting vehicle safely traveling through an intersection, such as lights and sirens, which prevent this from being a HIGH. DISC: THEA and NYC believe this to be LOW: "not necessary for the app to work; can cope with not having immediately available data" | |||
ITS Roadway Equipment | Traffic Management Center | roadway dynamic signage status | Moderate | Moderate | Moderate |
Device status information should not be available, as those with criminal intent may use this information toward their own ends. | Data is intended to feed dissemination channels, either C-ITS messages or DMS or other channels, so it should generally be correct as it is distributed widely and any forgery or corrupted data will have widespread impact. | Failure of this flow affects traveler information dissemination, the importance of which varies with the data contained in the flow and the scenario. Could be LOW in many instances. | |||
ITS Roadway Equipment | Traffic Management Center | signal control status | Low | High | Moderate |
The current conditions of an ITS RE are completely observable, by design. | This influences the TMC response to a right-of-way request. It should be as accurate as the right-of-way request themselves. For some applications (ISIG) this need only be moderate. Per THEA: info needs to be accurate and should not be tampered to enable effective monitoring and control by the TMC. DISC: THEA believes this to be MODERATE: "info needs to be accurate and should not be tampered to enable effective monitoring and control by the TMC; should be as accurate as the right of way request". NYC:TMC doesn't play an active role in this application, i.e. even if the information contained in this flow were incorrect, it is unlikely to affect the outcome of this application one way or the other. On some applications NYC has this MODERATE though. RES: This value can obviously change a lot depending on the application context. | The TMC will need the current status of the ITS RE in order to make an educated decision. If it is unavailable, the system is unable to operate. However, a few missed messages will not have a catastrophic impact. From NYC: 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 value can change a lot depending on the application context. | |||
ITS Roadway Equipment | Traffic Management Center | signal fault data | Low | High | Moderate |
The current conditions of an ITS RE are completely observable, by design. | Control flows, even for seemingly innocent devices, should have MODERATE integrity at minimum, just to guarantee that intended control messages are received. Incorrect, corrupted, intercepted and modified control messages can or will result in target field devices not behaving according to operator intent. The severity of this depends on the type of device, which is why some devices are set MODERATE and some HIGH. | Control flow availability is related to the criticality of being able to remotely control the device. For most devices, this is MODERATE. | |||
Multimodal Crossing Equipment | ITS Roadway Equipment | multimodal crossing status | Low | Moderate | Low |
There should be no sensitive information in this flow. Raise to MODERATE if reverse engineering of a proprietary interface is a concern. | This information can indicate when a road is closed to due a drawbridge being raised, which has a significant effect on traffic. If this information were falsified, it could have a significant negative effect on mobility over a large area. | Should not require rapid response or frequent update. Raise to MODERATE if frequent real-time updates are part of the system scope. | |||
Multimodal Crossing Equipment | Traffic Management Center | multimodal crossing status | Low | Moderate | Low |
There should be no sensitive information in this flow. Raise to MODERATE if reverse engineering of a proprietary interface is a concern. | This information can indicate when a road is closed to due a drawbridge being raised, which has a significant effect on traffic. If this information were falsified, it could have a significant negative effect on mobility over a large area. | Should not require rapid response or frequent update. Raise to MODERATE if frequent real-time updates are part of the system scope. | |||
Traffic Management Center | ITS Roadway Equipment | roadway dynamic signage data | Moderate | Moderate | Moderate |
Device control information should not be available, as those with criminal intent may use this information toward their own ends. | Data is intended to feed dissemination channels, either C-ITS messages or DMS or other channels, so it should generally be correct as it is distributed widely and any forgery or corrupted data will have widespread impact. | Occasional outages of this flow will delay dissemination of the data to travelers (the eventual end user) which could have significant impacts on travel, both safety and mobility impacts. | |||
Traffic Management Center | ITS Roadway Equipment | signal control commands | Moderate | High | Moderate |
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. |
|||
Traffic Management Center | Multimodal Crossing Equipment | multimodal crossing inhibit | Low | Moderate | Low |
There should be no sensitive information in this flow. Raise to MODERATE if reverse engineering of a proprietary interface is a concern. | This information can indicate when a road is closed to due a drawbridge being raised, which has a significant effect on traffic. If this information were falsified, it could have a significant negative effect on mobility over a large area. | Should not require rapid response or frequent update. Raise to MODERATE if frequent real-time updates are part of the system scope. | |||
Traffic Management Center | Traffic Operations Personnel | traffic operator data | Moderate | Moderate | Moderate |
Backoffice operations flows should have minimal protection from casual viewing, as otherwise imposters could gain illicit control or information that should not be generally available. | Information presented to backoffice system operators must be consistent or the operator may perform actions that are not appropriate to the real situation. | The backoffice system operator should have access to system operation. If this interface is down then control is effectively lost, as without feedback from the system the operator has no way of knowing what is the correct action to take. | |||
Traffic Management Center | Transportation Information Center | road network conditions | Low | Moderate | Moderate |
No harm should come from seeing this data, as it is eventually intended for public consumption. | While accuracy of this data is important for decision making purposes, applications should be able to corroborate the data in many instances. Thus MODERATE generally. | Depends on the application; if mobility decisions that affect large numbers of travelers are made based on this data, then it is MODERATE. In more modest circumstances, it may be LOW. | |||
Traffic Operations Personnel | Traffic Management Center | traffic operator input | Moderate | High | High |
Backoffice operations flows should have minimal protection from casual viewing, as otherwise imposters could gain illicit control or information that should not be generally available. | Backoffice operations flows should generally be correct and available as these are the primary interface between operators and system. | Backoffice operations flows should generally be correct and available as these are the primary interface between operators and system. |
Standards
The following table lists the standards associated with physical objects in this service package. For standards related to interfaces, see the specific information flow triple pages.
Name | Title | Physical Object |
---|---|---|
ITE ATC | Advanced Transportation Controller | ITS Roadway Equipment |
ITE ATC API | Application Programming Interface Standard for the Advanced Transportation Controller | ITS Roadway Equipment |
ITE ATC ITS Cabinet | Intelligent Transportation System Standard Specification for Roadside Cabinets | ITS Roadway Equipment |
ITE ATC Model 2070 | Model 2070 Controller Standard | ITS Roadway Equipment |
NEMA TS 8 Cyber and Physical Security | Cyber and Physical Security for Intelligent Transportation Systems | ITS Roadway Equipment |
Traffic Management Center | ||
NEMA TS2 Traffic Controller Assemblies | Traffic Controller Assemblies with NTCIP Requirements | ITS Roadway Equipment |
NEMA TS4 Hardware Standards for DMS | Hardware Standards for Dynamic Message Signs (DMS) With NTCIP Requirements | ITS Roadway Equipment |
System Requirements
System Requirement | Need | ||
---|---|---|---|
001 | The system shall remotely control traffic signal controllers for use at major multimodal crossings. | 01 | Traffic Operations need to be able to manage traffic control equipment at drawbridges at rivers, canals and other multimodal crossings. |
002 | The system shall remotely control driver information systems (such as dynamic messages signs, highway advisory radios (HAR), and equipment that controls warning lights and gates) to notify drivers of closure durations and times at multimodal crossings. | 02 | Traffic Operations need to be able to issue drawbridge crossing status information for drivers. |
003 | The system shall collect operational status for the equipment at multimodal crossings. | 01 | Traffic Operations need to be able to manage traffic control equipment at drawbridges at rivers, canals and other multimodal crossings. |
004 | The system shall collect fault data for the equipment at multimodal crossings for repair. | 01 | Traffic Operations need to be able to manage traffic control equipment at drawbridges at rivers, canals and other multimodal crossings. |
005 | The system shall distribute multimodal crossing information to other centers for dissemination to travelers. | 02 | Traffic Operations need to be able to issue drawbridge crossing status information for drivers. |
006 | The system shall include sensors to monitor requests from non-highway traffic to cross at multimodal crossings for specified durations (such as draw bridges and miscellaneous other interference crossings between highway traffic and other modes such as riv | 01 | Traffic Operations need to be able to manage traffic control equipment at drawbridges at rivers, canals and other multimodal crossings. |
007 | The system shall include signals to control traffic at multimodal crossings on surface streets, under center control. | 01 | Traffic Operations need to be able to manage traffic control equipment at drawbridges at rivers, canals and other multimodal crossings. |
008 | The system shall include driver information systems (such as dynamic messages signs, highway advisory radios (HAR), and equipment that controls warning lights and gates) that advise drivers at multimodal crossings, under center control. | 02 | Traffic Operations need to be able to issue drawbridge crossing status information for drivers. |
009 | The system shall provide operational status for the sensors, signals, and driver information systems equipment at multimodal crossings to the center. | 01 | Traffic Operations need to be able to manage traffic control equipment at drawbridges at rivers, canals and other multimodal crossings. |
010 | The system shall provide fault data for the sensors, signals, and driver information systems equipment at multimodal crossings to the center for repair. | 01 | Traffic Operations need to be able to manage traffic control equipment at drawbridges at rivers, canals and other multimodal crossings. |
011 | The system shall forward all requests for right-of-way at multimodal crossings to the controlling center. | 01 | Traffic Operations need to be able to manage traffic control equipment at drawbridges at rivers, canals and other multimodal crossings. |