Emergency Vehicle Subsystem

This subsystem resides in an emergency vehicle and provides the sensory, processing, storage, and communications functions necessary to support safe and efficient incident response. The subsystem represents a range of vehicles including those operated by police, fire, and emergency medical services. In addition, this subsystem represents other incident response vehicles including towing and recovery vehicles and freeway service patrols. The Emergency Vehicle Subsystem includes two-way communications to support coordinated response to emergencies in accordance with an associated Emergency Management Subsystem. Emergency vehicles are equipped with automated vehicle location capability for monitoring by vehicle tracking and fleet management functions in the Emergency Management Subsystem. Using these capabilities, the appropriate emergency vehicle to respond to each emergency is determined. Route guidance capabilities within the vehicle enable safe and efficient routing to the emergency. In addition, the emergency vehicle may be equipped to support signal preemption through communications with the Roadway Subsystem.

Security Considerations

The Emergency Vehicle Subsystem (EVS) is the communications lifeline that connects emergency personnel in the field with emergency dispatch, other emergency personnel, and other resources that support emergency response. The EVS handles potentially sensitive information, must "operate through" and be available in distressed environments, and is exposed to numerous threats including eavesdropping (disclosure), unauthorized access or control, and disruption of services. Although confidentiality is a concern, the most critical security objectives for EVS are availability and integrity - the services and information provided by EVS must be available and accurate so that incident response is not degraded. Although the EVS provides the same basic driver communications, tracking, and routing functions that are provided by the other fleet vehicle subsystems, these functions are frequently safety critical for this subsystem since they directly impact the ability to provide an effective response to emergencies, which in turn impacts public safety.

The EVS represents a wide range of vehicles including police cruisers, command vehicles, various types of fire apparatus, service patrol vehicles, ambulances, towing and recovery vehicles, and many different specialized response vehicles. This collection of vehicles may have very different security requirements, depending on the functions supported, the data that is stored, and the mission criticality of the services provided. For example, maintaining confidentiality of police vehicle locations is a public safety concern and frequently a key security objective. Tow vehicle locations are generally not a public safety concern, but tow truck operators may still want to prevent unauthorized vehicle location disclosure for business reasons. Finally, the current location of a service patrol vehicle may not be considered to be particularly sensitive.

There are also other variables that impact security that are independent of vehicle type. For example, initial EVS data services will supplement voice communications that frequently will continue to carry all mission critical information. The security requirements for these initial implementations might be less robust until the agency gains experience with the EVS data services and begins to rely on them for mission critical information. As the role of the data services evolves and expands, the security requirements and the systems themselves must be revised so that mission critical systems are available and reliable when they are needed most. The specific analysis of the security objectives, threats, vulnerabilities to those threats, and appropriate security services to address the vulnerabilities should be undertaken for systems associated with the EVS.

Functionality: Equipment Packages and PSpecs

• On-board EV Barrier System Control
  
  • 5.3.5 - Provide Emergency Personnel Interface
  • 5.3.8 - Control Barrier Systems From Emergency Vehicle
  
  
• On-board EV En Route Support
  
  • 5.3.3 - Provide Emergency Vehicle Location
  • 5.3.5 - Provide Emergency Personnel Interface
  
  
• On-board EV Incident Management Communication
  
  • 5.3.5 - Provide Emergency Personnel Interface
  
  

Inputs/Outputs: Architecture Flows and Data Flows

Care Facility > Emergency Vehicle Subsystem

• care facility status - Information regarding facility type and capabilities, facility status, and its ability to admit new patients.
  Data Flows:
  • fcf-care_facility_vehicle_status_response
  
  

Emergency Management > Emergency Vehicle Subsystem

• decision support information - Information provided to support effective and safe incident response, including local traffic, road, and weather conditions, hazardous material information, and the current status of resources that have been allocated to an incident.
  Data Flows:
  • local_decision_support
  
  
• emergency dispatch requests - Emergency vehicle dispatch instructions including incident location and available information concerning the incident.
  Data Flows:
  • emergency_vehicle_dispatch_request
  
  
• suggested route - Suggested route for a dispatched emergency or maintenance vehicle that may reflect current network conditions and the additional routing options available to en route emergency or maintenance vehicles that are not available to the general public.
  Data Flows:
  • emergency_vehicle_suggested_route
  
  

Emergency Personnel > Emergency Vehicle Subsystem

• emergency personnel inputs - User input from emergency personnel in the field including dispatch coordination, incident status information, and remote device control requests.
  Data Flows:
  • fep-emergency_dispatch_acknowledge
  • fep-incident_status
  • fep-barrier_system_control
  
  

Emergency Vehicle Subsystem > Care Facility

• care facility status request - Request for information regarding care facility availability and status.
  Data Flows:
  • tcf-care_facility_vehicle_status_request
  
  
• patient status - Information that supports assessment of the patient's condition. Information could include general categorization of patient status, patient vital signs, pertinent medical history, and emergency care information.
  Data Flows:
  • tcf-emergency_vehicle_patient_status_update
  
  

Emergency Vehicle Subsystem > Emergency Management

• emergency dispatch response - Request for additional emergency dispatch information and provision of en route status.
  Data Flows:
  • emergency_vehicle_dispatch_response
  
  
• emergency vehicle tracking data - The current location and operating status of the emergency vehicle.
  Data Flows:
  • emergency_vehicle_tracking_data
  
  
• incident status - Information gathered at the incident site that more completely characterizes the incident and provides current incident response status.
  Data Flows:
  • incident_status_update
  
  

Emergency Vehicle Subsystem > Emergency Personnel

• 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.
  Data Flows:
  • tep-decision_support
  • tep-emergency_dispatch_order
  • tep-barrier_system_status
  
  

Emergency Vehicle Subsystem > Roadway Subsystem

• barrier system control - Information used to configure and control barrier systems that are represented by gates, barriers and other automated or remotely controlled systems used to manage entry to roadways.
  Data Flows:
  • barrier_system_control_from_emerg_veh
  
  
• local signal preemption request - Direct control signal or message to a signalized intersection that results in preemption of the current control plan and grants right-of-way to the requesting vehicle.
  Data Flows:
  • emergency_vehicle_preemptions
  
  

Emergency Vehicle Subsystem > Vehicle

• emergency vehicle alert - Notification to vehicles in the area that an emergency vehicle is in the vicinity. The number of responding vehicles, their status, location, speed, and direction are provided.
  Data Flows:
  • emergency_vehicle_proximity
  
  
• vehicle signage data - In-vehicle signing data that augments regulatory, warning, and informational road signs and signals. The information provided would include static sign information (e.g., stop, curve warning, guide signs, service signs, and directional signs) and dynamic information (e.g., current signal states, grade crossing information, local traffic and road conditions, advisories, and detours).
  Data Flows:
  • em_to_vehicle_incident_scene_information
  
  

Location Data Source > Emergency Vehicle Subsystem

• position fix - Information which provides a traveller's or vehicle's geographical position.
  Data Flows:
  • From_Location_Data_Source
  
  

Roadway Subsystem > Emergency Vehicle Subsystem

• barrier system status - Current operating status of barrier systems. Barrier systems represent gates, barriers and other automated or remotely controlled systems used to manage entry to roadways. Status of the systems includes operating condition and current operational state.
  Data Flows:
  • barrier_system_status_to_emerg_veh