< < PS03.6 : PS03.7 : PS04.1 > >
PS03.7: MEC Supported Implementation
Multi-Access Edge Computing (MEC) at the local Wide-Area Wireless (WAW) node processes the signal preemption request at the edge of the WAW network, coordinating with the signal controller to preempt the signal for the emergency vehicle, reducing latency and WAW communications network traffic.
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 |
|---|---|---|
| Emergency Personnel | Emergency Vehicle OBE | Operates |
| Emergency Personnel | ITS Roadway Equipment | Operates |
| Emergency Vehicle OBE Maintainer | Emergency Vehicle OBE | Maintains |
| Emergency Vehicle OBE Manager | Emergency Personnel | System Usage Agreement |
| Emergency Vehicle OBE Manager | Emergency Vehicle OBE | Manages |
| Emergency Vehicle OBE Owner | Emergency Vehicle OBE Maintainer | System Maintenance Agreement |
| Emergency Vehicle OBE Owner | Emergency Vehicle OBE Manager | Operations Agreement |
| Emergency Vehicle OBE Supplier | Emergency Vehicle OBE Owner | Warranty |
| ITS Roadway Equipment Maintainer | ITS Roadway Equipment | Maintains |
| ITS Roadway Equipment Manager | Emergency Personnel | System Usage Agreement |
| 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 Supplier | ITS Roadway Equipment 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 |
|---|---|---|
| Emergency Personnel | Vehicle | 'Emergency Personnel' represents personnel that are responsible for police, fire, emergency medical services, towing, service patrols, and other special response team (e.g., hazardous material clean-up) activities at an incident site. These personnel are associated with the Emergency Vehicle during dispatch to the incident site, but often work independently of the Emergency Vehicle while providing their incident response services. |
| Emergency Vehicle OBE | Vehicle | The 'Emergency Vehicle On-Board Equipment' (OBE) resides in an emergency vehicle and provides the processing, storage, and communications functions that support public safety-related connected vehicle applications. It represents a range of vehicles including those operated by police, fire, and emergency medical services. In addition, it represents other incident response vehicles including towing and recovery vehicles and freeway service patrols. It includes two-way communications to support coordinated response to emergencies. A separate 'Vehicle OBE' physical object supports the general vehicle safety and driver information capabilities that apply to all vehicles, including emergency vehicles. The Emergency Vehicle OBE supplements these general capabilities with capabilities that are specific to emergency vehicles. |
| 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. |
| Multi-Access Edge Computing | Field | 'Multi-Access Edge Computing' ((MEC) previously known as mobile edge computing) represents computing devices that operate and are managed like a cloud server, but are deployed at the edge of a network (typically a cellular network, but it could be any network). While not in strict proximity to the transportation network, these systems do benefit from vastly decreased distances to the roadway compared to central systems, and so can provide lower latency than strictly backoffice systems |
| 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. |
Includes Functional Objects:
| Functional Object | Description | Physical Object |
|---|---|---|
| EV On-Board En Route Support | 'EV On-Board En Route Support' provides communications functions to responding emergency vehicles that reduce response times and improve safety of responding public safety personnel and the general public. It supports traffic signal preemption via short range communication directly with signal control equipment. | Emergency Vehicle OBE |
| MEC Intersection Management | 'MEC Intersection Management' uses cellular communications to support connected vehicle applications that manage signalized intersections. It communicates with nearby vehicles and ITS infrastructure (e.g., the traffic signal controller) to enhance traffic signal operations. There may be constraints related to performance related to communications with participants using network operators foreign to the MEC. | Multi-Access Edge Computing |
| 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 |
| 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 |
| Vehicle Basic Safety Communication | 'Vehicle Basic Safety Communication' exchanges current vehicle characteristics, location, and motion (including past and intended maneuver) information with other vehicles in the vicinity and the infrastructure, uses that information to calculate vehicle paths, and warns the driver when the potential for an impending collision is detected. If available, map data is used to filter and interpret the relative location and motion of vehicles in the vicinity. Information from on-board sensors (e.g., radars and image processing) are also used, if available, in combination with the V2V communications to detect non-equipped vehicles and corroborate connected vehicle data. This object represents a broad range of implementations ranging from basic Vehicle Awareness Devices that only broadcast vehicle location and motion and provide no driver warnings to advanced integrated safety systems that coordinate maneuvers and may, in addition to warning the driver, provide collision warning information to support automated control functions that can support control intervention. This object can also support broadcasting other vehicle information required for passing through a specific roadway segment such as variables that describe vehicle's characteristics and parameters, driver's preferences in terms of vehicle motion and behavior, etc. | Vehicle |
| 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. |
| emergency personnel information presentation | Presentation of information to emergency personnel in the field including dispatch information, incident information, current road network conditions, device status, and other supporting information. |
| emergency personnel input | User input from emergency personnel in the field including dispatch coordination, incident status information, and remote device control requests. |
| intersection control status | Status data provided by the traffic signal controller including phase information, alarm status, and priority/preempt status. |
| 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 management application info | Intersection and device configuration data, including intersection geometry, and warning parameters and thresholds. This flow also supports remote control of the application so the application can be taken offline, reset, or restarted. |
| intersection management application status | Infrastructure application status including current operational state and status of the field device and a log of operations. |
| 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 preemption request | Direct request for preemption to a traffic signal controller that results in preemption of the current control plan and grants right-of-way to the requesting vehicle. This flow identifies the required phase and timing of the preemption. This flow may also cancel the preemption request (e.g., when the requesting vehicle clears the intersection). |
| signal priority status | In response to a request for signal priority, this flow indicates the status of the priority or preemption request. |
| vehicle location and motion | Data describing the vehicle's location in three dimensions, heading, speed, acceleration, braking status, and size. |
Goals and Objectives
Associated Planning Factors and Goals
| Planning Factor | Goal |
|---|
Associated Objective Categories 
| Objective Category |
|---|
Associated Objectives and Performance Measures 
| Objective | Performance Measure |
|---|
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 |
| Emergency Vehicle OBE | ||||
| ITS Roadway Equipment | ||||
| Multi-Access Edge Computing | ||||
| Traffic Management Center | ||||
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 | |||
| Emergency Personnel | Emergency Vehicle OBE | emergency personnel input | Moderate | Moderate | Moderate |
| Some of the information, such as incident status information, is sensitive, and should be protected. | The system must know that these requests came from actual Emergency Personal. Additionally, incorrect information here may lead to the system responding incorrectly to the incident | These messages are important for the system to operate properly. Additionally, the system must know if messages are not received so that it can act accordingly. | |||
| Emergency Vehicle OBE | Emergency Personnel | emergency personnel information presentation | Moderate | Moderate | Moderate |
| Some of this information, such as incident information, is sensitive and should be protected. | This information could affect how the Emergency Personnel respond to the event, and should be as accurate as possible. | This information needs to be available for the Emergency Personnel in order for them to respond accurately to the system. If they do not acknowledge this information, dispatch needs to know, so they can attempt to contact the Emergency Personnel via another channel, such as radio. | |||
| ITS Roadway Equipment | Emergency Personnel | driver information | Not Applicable | High | High |
| 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 | Multi-Access Edge Computing | intersection control status | Moderate | High | Moderate |
| This data is intentionally transmitted to everyone via a While this information is broadcast and can also be determined via other visual indicators, all communications between field infrastructure should be protected from viewing to prevent attackers from analyzing traffic and developing attack methods. | If this is compromised, the Roadway Equipment and Roadside Equipment will be sending messages that are inconsistent with each other, leading to confusion and possible accidents. | If this is down, the RSE doesn’t get the information it needs to stay in synch with the actual signal state, reducing or eliminating the value add from having this application. The RSE must detect a lack of availability and choose not to send out-of-date information, so a failure of availability could be interpreted as having the same value as Integrity. However, this data is semi-predictable and there are other indicators (such as the lights themselves) of the intersection status. From NYC, who believe this should be HIGH for some applications: If this is down, the RSE doesn’t get the information it needs to stay in synch with the actual signal state, reducing or eliminating the value add from having this application. The RSE must detect a lack of availability and choose not to send out-of-date information, so a failure of availability cannot have worse consequences than a failure of integrity which we have previously assessed at HIGH. | |||
| Multi-Access Edge Computing | Emergency 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. | |||
| Multi-Access Edge Computing | ITS Roadway Equipment | signal preemption request | Moderate | High | Moderate |
| It does not matter if someone is able to eavesdrop on this request. There will be many other more obvious indicators that the request was made, such as sirens and flashing lights on the emergency vehicle; however, all communications between field infrastructure should be protected from viewing to prevent attackers from analyzing traffic and developing attack methods. | The system must be able to trust these requests. Emergency Vehicles should be able to send these requests and know that they are being operated on by the receiving system. Additionally, if an unauthorized vehicle is able to send these requests it could bring traffic to a standstill by disrupting signal coordination citywide. | The alternative to this request is existing mechanisms – such as using the sirens to stop traffic. The difference between the emergency signal preemption application and existing practice is not significant enough to justify a HIGH availability requirement. | |||
| Multi-Access Edge Computing | Traffic Management Center | intersection management application status | Moderate | Moderate | Low |
| This information could be of interest to a malicious individual who is attempting to determine the best way to accomplish a crime. As such it would be best to not make it easily accessible. May be LOW in some cases. | If this is compromised, it could send unnecessary maintenance workers, or worse report plausible data that is erroneous. From THEA: should be able to cope with some bad information on the status and record of alerts/warnings; aggregate info; however could cause appearance of excessive traffic violations or unnecessary maintenance caused if data is compromised (operational state, status, log); should not affect the application functionality | Incident status information should be presented in timely fashion as large scale mobility and safety issues are related. There are other mechanisms for reporting this information however, thus MODERATE. From THEA: Only limited adverse effect of info is not timely/readily available | |||
| Traffic Management Center | Multi-Access Edge Computing | intersection management application info | Moderate | High | Low |
| Proprietary configuration data with warning parameters and thresholds. | should be accurate and not be tampered with; could enable outside control of application | This message is an indication of a potential hazard. If it isn’t received it increases the risk to other road users. If a vehicle is infringing on an intersection, it must report this. | |||
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 |