< < PT09.5 : PT09.6 : PT09.7 > >
PT09.6: Wide Area Wireless Implementation
Signal Priority is requested via wide-area wireless (e.g., cellular) to a third-party provider that coordinates with the Traffic Management Center to grant signal priority to the transit vehicle.
Relevant Regions:
- 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
(hide)
| Source | Destination | Role/Relationship |
|---|---|---|
| TIC Operator | Transportation Information Center | Operates |
| 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 | TIC Operator | Application Usage 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 Maintainer | Maintenance Data Exchange Agreement |
| Traffic Management Center Owner | Transportation Information Center Owner | Information Provision Agreement |
| Traffic Management Center Owner | Transportation Information Center User | Service Usage Agreement |
| Traffic Management Center Supplier | Traffic Management Center Owner | Warranty |
| Traffic Operations Personnel | Traffic Management Center | Operates |
| Transit Vehicle OBE Maintainer | Transit Vehicle OBE | Maintains |
| Transit Vehicle OBE Manager | Transit Vehicle OBE | Manages |
| Transit Vehicle OBE Manager | Transit Vehicle Operator | System Usage Agreement |
| Transit Vehicle OBE Owner | Transit Vehicle OBE Maintainer | System Maintenance Agreement |
| Transit Vehicle OBE Owner | Transit Vehicle OBE Manager | Operations Agreement |
| Transit Vehicle OBE Supplier | Transit Vehicle OBE Owner | Warranty |
| Transit Vehicle Operator | Transit Vehicle OBE | Operates |
| Transportation Information Center Maintainer | Transportation Information Center | Maintains |
| Transportation Information Center Manager | TIC Operator | System Usage Agreement |
| Transportation Information Center Manager | Transportation Information Center | Manages |
| Transportation Information Center Owner | Transit Vehicle OBE Maintainer | Maintenance Data Exchange Agreement |
| Transportation Information Center Owner | Transit Vehicle OBE Owner | Information Provision Agreement |
| Transportation Information Center Owner | Transit Vehicle OBE User | Service Usage Agreement |
| Transportation Information Center Owner | Transit Vehicle Operator | Application Usage Agreement |
| 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 |
|---|---|---|
| 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. |
| 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. |
| Transit Management Center | Center | The 'Transit Management Center' manages transit vehicle fleets and coordinates with other modes and transportation services. It provides operations, maintenance, customer information, planning and management functions for the transit property. It spans distinct central dispatch and garage management systems and supports the spectrum of fixed route, flexible route, paratransit services, transit rail, and bus rapid transit (BRT) service. The physical object's interfaces support communication between transit departments and with other operating entities such as emergency response services and traffic management systems. |
| Transit Operations Personnel | Center | 'Transit Operations Personnel' represents the people that are responsible for fleet management, maintenance operations, and scheduling activities of the transit system. These different roles represent a variety of individuals in the transit industry. Within the transit industry the person responsible for fleet management is known by many names: Street Supervisor, Starter, Dispatcher, Supervisor, Traffic Controller, Transportation Coordinator. This person actively monitors, controls, and modifies the transit fleet routes and schedules on a day to day basis (dynamic scheduling). The modifications will take account of abnormal situations such as vehicle breakdown, vehicle delay, detours around work zones or incidents (detour management, connection protection, and service restoration), and other causes of route or schedule deviations. Transit operations personnel are also responsible for demand responsive transit operation and for managing emergency situations within the transit network such as silent alarms on board transit vehicles, or the remote disabling of the vehicle. In addition the Transit Operations Personnel may be responsible for assigning vehicle operators to routes, checking vehicle operators in and out, and managing transit stop issues. This object also represents the personnel in the transit garage that are responsible for maintenance of the transit fleets, including monitoring vehicle status, matching vehicles with operators, and maintenance checking of transit vehicles. Finally, it represents the people responsible for planning, development, and management of transit routes and schedules. |
| Transit Vehicle OBE | Vehicle | The 'Transit Vehicle On-Board Equipment' (OBE) resides in a transit vehicle and provides the sensory, processing, storage, and communications functions necessary to support safe and efficient movement of passengers. The types of transit vehicles containing this physical object include buses, paratransit vehicles, light rail vehicles, other vehicles designed to carry passengers, and supervisory vehicles. It collects ridership levels and supports electronic fare collection. It supports a traffic signal prioritization function that communicates with the roadside physical object to improve on-schedule performance. Automated vehicle location enhances the information available to the transit operator enabling more efficient operations. On-board sensors support transit vehicle maintenance. The physical object supports on-board security and safety monitoring. This monitoring includes transit user or vehicle operator activated alarms (silent or audible), as well as surveillance and sensor equipment. The surveillance equipment includes video (e.g. CCTV cameras), audio systems and/or event recorder systems. It also furnishes travelers with real-time travel information, continuously updated schedules, transfer options, routes, and fares. A separate 'Vehicle OBE' physical object supports the general vehicle safety and driver information capabilities that apply to all vehicles, including transit vehicles. The Transit Vehicle OBE supplements these general capabilities with capabilities that are specific to transit vehicles. |
| Transit Vehicle Operator | Vehicle | The 'Transit Vehicle Operator' represents the person that receives and provides additional information that is specific to operating the ITS functions in all types of transit vehicles. The information received by the operator would include status of on-board systems. Additional information received depends upon the type of transit vehicle. In the case of fixed route transit vehicles, the Transit Vehicle Operator would receive operator instructions that might include actions to take to correct schedule deviations. In the case of flexible fixed routes and demand response routes the information would also include dynamic routing or passenger pickup information. |
| 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 Signal Control | 'Roadway Signal Control' includes the field elements that monitor and control signalized intersections. It includes the traffic signal controllers, detectors, conflict monitors, signal heads, and other ancillary equipment that supports traffic signal control. It also includes field masters, and equipment that supports communications with a central monitoring and/or control system, as applicable. The communications link supports upload and download of signal timings and other parameters and reporting of current intersection status. It represents the field equipment used in all levels of traffic signal control from basic actuated systems that operate on fixed timing plans through adaptive systems. It also supports all signalized intersection configurations, including those that accommodate pedestrians. In advanced, future implementations, environmental data may be monitored and used to support dilemma zone processing and other aspects of signal control that are sensitive to local environmental conditions. | ITS Roadway Equipment |
| TIC Traffic Control Dissemination | 'TIC Traffic Control Dissemination' serves as intermediary between transportation operations centers (e.g., TMC, Transit MC) and transportation users (e.g., vehicles, personal devices). It collects and disseminates intersection status, lane control information, special vehicle alerts, and other traffic control related information that is real-time or near real-time in nature and relevant to vehicles in a relatively local area on the road network. It collects traffic control information from Traffic Management and other Center(s) and disseminates the relevant information to vehicles and other mobile devices. | Transportation Information Center |
| TMC Multi-Modal Coordination | 'TMC Multi-Modal Coordination' supports center-to-center coordination between the Traffic Management and Transit Management Centers. It monitors transit operations and provides traffic signal priority for transit vehicles on request from the Transit Management Center. | Traffic Management Center |
| TMC Signal Control | 'TMC Signal Control' provides the capability for traffic managers to monitor and manage the traffic flow at signalized intersections. This capability includes analyzing and reducing the collected data from traffic surveillance equipment and developing and implementing control plans for signalized intersections. Control plans may be developed and implemented that coordinate signals at many intersections under the domain of a single Traffic Management Center and are responsive to traffic conditions and adapt to support incidents, preemption and priority requests, pedestrian crossing calls, etc. This may include adaptive traffic control systems (ATCS) that adjust signal timings based on traffic conditions, demand, and system capacity. It also supports all signalized intersection configurations, including those that accommodate pedestrians. | Traffic Management Center |
| Transit Center Priority Management | 'Transit Center Priority Management' monitors transit schedule performance and generates requests for transit priority on routes and at certain intersections. It may coordinate with the Traffic Management Center to provide transit priority along the selected route, including allocation of dynamic lanes and granting signal priority. It also coordinates with the Transit Vehicle OBE to monitor and manage local transit signal priority requests at individual intersections. | Transit Management Center |
| Transit Vehicle Signal Priority | 'Transit Vehicle Signal Priority' provides the capability for transit vehicles to determine eligibility for priority and request signal priority at signalized intersections, ramps, and interchanges through short range communication with traffic control equipment at the roadside. | Transit Vehicle OBE |
| Vehicle Intersection Movement | 'Vehicle Intersection Movement' uses short-range wireless communications to monitor other connected vehicles at intersections and support the safe movement of the vehicle through the intersection by receiving and processing signal phase and timing messages from the intersection. Driver warnings are provided and the application may also optionally take control of the vehicle to avoid collisions, in coordination with Vehicle Control Automation. The application will also notify the infrastructure and other vehicles if it detects an unsafe infringement on the intersection. | Vehicle |
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. |
| intersection geometry | The physical geometry of an intersection covering the location and width of each approaching lane, egress lane, and valid paths between approaches and egresses. This flow also defines the location of stop lines, cross walks, specific traffic law restrictions for the intersection (e.g., turning movement restrictions), and other elements that support calculation of a safe and legal vehicle path through the intersection. |
| intersection status | Current signal phase and timing information for all lanes at a signalized intersection. This flow identifies active lanes and lanes that are being stopped and specifies the length of time that the current state will persist for each lane. It also identifies signal priority and preemption status and pedestrian crossing status information where applicable. It may also include future signal phase and timing information. |
| signal priority request | Request from a vehicle for priority at an intersection. The request may include the priority level, the desired time and duration of service, and the intended travel path through the intersection. This flow may also allow the originator to cancel a previously issued request for priority. |
| signal priority service request | A service request for vehicle priority issued to a traffic signal controller. The request includes the priority level, and may include other parameters such as the desired time and duration of service, and the intended travel path through the intersection. This flow also allows the originator to cancel a previously issued request for priority. |
| signal priority status | In response to a request for signal priority, this flow indicates the status of the priority or preemption request. |
| traffic control priority request | Request for signal priority at one or more intersections along a particular route. |
| traffic control priority status | Status of signal priority request functions at the roadside (e.g., enabled or disabled). |
| transit operations personnel input | User input from transit operations personnel including instructions governing service availability, schedules, emergency response plans, transit personnel assignments, transit maintenance requirements, and other inputs that establish general system operating requirements and procedures. |
| transit operations status | Presentation of information to transit operations personnel including accumulated schedule and fare information, ridership and on-time performance information, emergency response plans, transit personnel information, maintenance records, and other information intended to support overall planning and management of a transit property. |
Goals and Objectives
Associated Planning Factors and Goals
| Planning Factor | Goal |
|---|
Associated Objective Categories 
| Objective Category |
|---|
Associated Objectives and Performance Measures
| Objective | Performance Measure |
|---|
Since the mapping between objectives and service packages is not always straight-forward and often situation-dependent, these mappings should only be used as a starting point. Users should do their own analysis to identify the best service packages for their region.
Needs and Requirements
| Need | Functional Object | Requirement | ||
|---|---|---|---|---|
Related Sources
| Document Name | Version | Publication Date |
|---|---|---|
| None |
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 | ||||
| Traffic Management Center | Not Applicable | High | Moderate | Class 3 |
| Transit Management Center | ||||
| Transit Vehicle OBE | ||||
| Transportation Information Center | Not Applicable | High | Moderate | Class 3 |
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 | Transit Vehicle Operator | 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 will happen. | If the lights are out you have to get a policeman to direct traffic – expensive and inefficient and may cause a knock-on effect due to lack of coordination with other intersections. | |||
| Traffic Management Center | ITS Roadway Equipment | signal priority service request | Not Applicable | Moderate | Low |
| There is no sensitive or confidential information within this messages. Additionally, it could be inferred by observing either the presence of a priority-requesting vehicle near an intersection, or the effect on the timing of the intersection. This is also transmitted as a result of broadcast data. | The TMC is transmitting a request to the ITS RE on behalf of a priority-requesting vehicle. It should only be making requests on behalf of an approved vehicle. A corrupted request may lead to a vehicle not receiving a green light after requesting it. In this case, this may lead to traffic delays. If an unapproved vehicle is able to forge these requests, they may cause larger scale traffic delays. | If the ITS RE does not receive any requests, the vehicle may not receive the priority it requested. In the worst case scenario the vehicle would be forced to wait at some lights until they turned green. It would be more useful for a device to support this application, and only have some messages received, than to not support this application at all. | |||
| Traffic Management Center | Transportation Information Center | intersection status | Not Applicable | High | Moderate |
| This data is distributed using a variety of mechanisms, some of which are localized broadcast; it is desireable that all potential users get this information. | If this flow is not accurate or delivered in a timely fashion then a large variety of mobility and safety services that depend on it will not work properly. | If this flow is not accurate or delivered in a timely fashion then a large variety of mobility and safety services that depend on it will not work properly. | |||
| Traffic Management Center | Transportation Information Center | traffic control priority status | Not Applicable | Moderate | Moderate |
| The result of this will be directly observable. | Invalid messages could lead to an unauthorized user gaining transit 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). | These messages are important to help with the transit signal priority application. Without them, it will not work. However, if these signals are not received, the ITS RE will continue to function using its default configuration. The Transit Management Center should have an acknowledgement of the receipt of a message. | |||
| Transit Management Center | Transit Operations Personnel | transit operations status | 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. | |||
| Transit Operations Personnel | Transit Management Center | transit operations personnel 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. | |||
| Transit Vehicle OBE | Transportation Information Center | signal priority request | Not Applicable | Moderate | Low |
| There is no sensitive or confidential information within this messages. Additionally, it could be inferred by observing either the presence of a priority-requesting vehicle near an intersection, or the effect on the timing of the intersection. This is also transmitted as a result of broadcast data. | Only specific vehicles that have been granted authorization to receive priority/preemption should be able to send this request. Allowing other vehicles to send it could negatively impact the performance of the traffic signal network, so authentication and integrity mechanisms must ensure the message cannot be forged or altered. | If the CVRSE does not receive any requests, the vehicle may not receive the priority it requested. In the worst case scenario the vehicle would be forced to wait at some lights until they turned green. It would be more useful for a device to support this application, and only have some messages received, than to not support this application at all. | |||
| Transportation Information Center | Traffic Management Center | traffic control priority request | Not Applicable | Moderate | Moderate |
| The result of this will be directly observable. | Invalid messages could lead to an unauthorized user gaining transit 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). | These messages are important to help with the transit signal priority application. Without them, it will not work. However, if these signals are not received, the ITS RE will continue to function using its default configuration. The Transit Management Center should have an acknowledgement of the receipt of a message. | |||
| Transportation Information Center | Transit Vehicle OBE | signal priority status | Low | Moderate | Low |
| Not much could be learned by observing this flow, just the state of the priority request and the identity of the requester. Both of those are information that can be gleaned by physical observation, and give little advantage to an observer. | Signal priority status information enables the receiving vehicle to proceed with more surety toward's its next stop; while there are obvious redundancies, a degree of confidence in the state of the message is required for user acceptance if nothing else. | The most important aspect of this flow is the initiating request and hopefull success of that priority message; if that succeeds then the signal will turn in the vehicle's favor, making this flow a 'nice-to-have' that should be correct if it arrives, but is not necessary for the priority application to function. | |||
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. These pages can be accessed directly from the SVG diagram(s) located on the Physical tab, by clicking on each information flow line on the diagram.
| Name | Title | Physical Object |
|---|---|---|
| ITE 5201 ATC | Advanced Transportation Controller | ITS Roadway Equipment |
| ITE 5202 ATC Model 2070 | Model 2070 Controller Standard | ITS Roadway Equipment |
| ITE 5301 ATC ITS Cabinet | Intelligent Transportation System Standard Specification for Roadside Cabinets | ITS Roadway Equipment |
| ITE 5401 ATC API | Application Programming Interface Standard for the Advanced Transportation Controller | 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 |
System Requirements
| No System Requirements |