Architecture Flow Descriptions

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Architecture Flow Architecture Flow Description
alarm acknowledge Confirmation that alarm was received, instructions and additional information for the alarm initiator, and requests for additional information.
alarm notification Notification of activation of an audible or silent alarm by a traveler in a public area or by a transit vehicle operator using an on-board device.
alert notification Notification of a major emergency such as a natural or man-made disaster, civil emergency, or child abduction for distribution to the public. The flow identifies the alert originator, the nature of the emergency, the geographic area affected by the emergency, the effective time period, and information and instructions necessary for the public to respond to the alert. This flow may also identify specific information that should not be released to the public.
alert notification coordination Coordination of emergency alerts to be distributed to the public. This includes notification of a major emergency such as a natural or man-made disaster, civil emergency, or child abduction for distribution to the public and status of the public notification.
alert status Information indicating the current status of the emergency alert including identification of the traveler and driver information systems that are being used to provide the alert.
alerts and advisories Assessments (general incident and vulnerability awareness information), advisories (identification of threats or recommendations to increase preparedness levels), and alerts (information on imminent or in-progress emergencies). This flow also provides supporting descriptive detail on incidents, threats, and vulnerabilities to increase preparedness and support effective response to threats against the surface transportation system.
amber alert confirmation_ud Confirmation that the amber alert system commands have been received. Confirmation may include the messages that was activated and displayed.
amber alerts_ud Amber alert information to be placed on dynamic message signs controlled by a traffic management element.
archive requests A request to a data source for information on available data (i.e. "catalog") or a request that defines the data to be archived. The request can be a general subscription intended to initiate a continuous or regular data stream or a specific request intended to initiate a one-time response from the recipient.
archive status Notification that data provided to an archive contains erroneous, missing, or suspicious data or verification that the data provided appears valid. If an error has been detected, the offending data and the nature of the potential problem are identified.
archived data product requests A user-specified request for archived data products (i.e. data, meta data, or data catalogs). The request also includes information that is used to identify and authenticate the user and support electronic payment requirements, if any.
broadcast traveler information General traveler information that contains traffic and road conditions, link travel times, incidents, advisories, restrictions, transit service information, weather information, parking information, and other related traveler information.
broadcast traveler information_ud General traveler information that contains traffic and road conditions, link travel times, incidents, advisories, transit service information, weather information, parking information, and other related traveler information.
current asset restrictions Restrictions levied on transportation asset usage based on infrastructure design, surveys, tests, or analyses. This includes standard facility design height, width, and weight restrictions, special restrictions such as spring weight restrictions, and temporary facility restrictions that are imposed during maintenance and construction.
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.
demand response passenger and use data Data collected on board a demand response vehicle relating to the picking up and discharging of passengers.
demand responsive transit plan Plan regarding overall demand responsive transit schedules and deployment.
demand responsive transit request Request for paratransit support.
device control request Request for device control action
device data Data from detectors, environmental sensor stations, and traffic control devices including device inventory information.
device status Status information from devices
driver information Regulatory, warning, and guidance information provided to the driver while en route to support safe and efficient vehicle operation.
emergency archive data Logged emergency information including information that characterizes identified incidents (routine highway incidents through disasters), corresponding incident response information, evacuation information, surveillance data, threat data, and resource information. Content may include a catalog of available information, the actual information to be archived, and associated meta data that describes the archived information.
emergency dispatch requests Emergency vehicle dispatch instructions including incident location and available information concerning the incident.
emergency dispatch response Request for additional emergency dispatch information and provision of en route status.
emergency traveler information Public notification of an emergency such as a natural or man-made disaster, civil emergency, or child abduction. This flow also includes evacuation information including evacuation instructions, evacuation zones, recommended evacuation times, tailored evacuation routes and destinations, traffic and road conditions along the evacuation routes, traveler services and shelter information, and reentry times and instructions.
emergency traveler information request Request for alerts, evacuation information, and other emergency information provided to the traveling public.
emergency traveler information_ud Public notification of an emergency such as a natural or man-made disaster, civil emergency, or child abduction. This flow also includes evacuation information including evacuation instructions, evacuation zones, recommended evacuation times, tailored evacuation routes and destinations, traffic and road conditions along the evacuation routes, traveler services and shelter information, and reentry times and instructions.
emergency vehicle tracking data The current location and operating status of the emergency vehicle.
environmental conditions data Current road conditions (e.g., surface temperature, subsurface temperature, moisture, icing, treatment status) and surface weather conditions (e.g., air temperature, wind speed, precipitation, visibility) as measured and reported by fixed and/or mobile environmental sensors and aggregated by the data collector. Attributes relating to the data collection (and aggregation) are also included.
environmental conditions data status Status of the data quality of environmental conditions data provided by a data contributor. Includes not only status by sensor, but statistical data regarding the quality checking of data provided.
environmental sensor data Current road conditions (e.g., surface temperature, subsurface temperature, moisture, icing, treatment status) and surface weather conditions (e.g., air temperature, wind speed, precipitation, visibility) as measured and reported by fixed and/or mobile environmental sensors. Operational status of the sensors is also included.
environmental sensors control Data used to configure and control environmental sensors.
evacuation information Evacuation instructions and information including evacuation zones, evacuation times, and reentry times.
external reports Traffic and incident information that is collected by the media through a variety of mechanisms (e.g., radio station call-in programs, air surveillance).
fare collection data Fare collection information including the summary of on-board fare system data and financial payment transaction data.
hri operational status Status of the highway-rail grade crossing equipment including both the current state or mode of operation and the current equipment condition.
hri status Status of the highway-rail intersection equipment including both the current state or mode of operation and the current equipment condition.
incident information Notification of existence of incident and expected severity, location, time and nature of incident. As additional information is gathered and the incident evolves, updated incident information is provided. Incidents include any event that impacts transportation system operation ranging from routine incidents (e.g., disabled vehicle at the side of the road) through large-scale natural or human-caused disasters that involve loss of life, injuries, extensive property damage, and multi-jurisdictional response. This also includes special events, closures, and other planned events that may impact the transportation system.
incident information for media Report of current desensitized incident information prepared for public dissemination through the media.
incident report Report of an identified incident including incident location, type, severity and other information necessary to initiate an appropriate incident response.
incident report_ud Report of an identified incident including incident location, type, severity and other information necessary to initiate an appropriate incident response.
incident response coordination Incident response procedures and current incident response status that are shared between allied response agencies to support a coordinated response to incidents. This flow provides current situation information, including a summary of incident status and its impact on the transportation system and other infrastructure, and current and planned response activities. This flow also coordinates a positive hand off of responsibility for all or part of an incident response between agencies.
incident response coordination_ud Incident response procedures and current incident response status that are shared between allied response agencies to support a coordinated response to incidents. This flow provides current situation information, including a summary of incident status and its impact on the transportation system and other infrastructure, and current and planned response activities. This flow also coordinates a positive hand off of responsibility for all or part of an incident response between agencies.
incident response status Status of the current incident response including a summary of incident status and its impact on the transportation system, traffic management strategies implemented at the site (e.g., closures, diversions, traffic signal control overrides), and current and planned response activities.
incident status Information gathered at the incident site that more completely characterizes the incident and provides current incident response status.
interactive traveler information Traveler information provided in response to a traveler request. The provided information includes traffic and road conditions, advisories, incidents, payment information, transit services, parking information, weather information, and other travel-related data updates and confirmations.
lane management control Information used to configure and control dynamic lane management systems.
lane management information System status including current operational state, violations, and logged information.
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.
local signal priority request Request from a vehicle to a signalized intersection for priority at that intersection.
maint and constr archive data Information describing road construction and maintenance activities identifying the type of activity, the work performed, and work zone information including work zone configuration and safety (e.g., a record of intrusions and vehicle speeds) information. For construction activities, this information also includes a description of the completed infrastructure, including as-built plans as applicable. Content may include a catalog of available information, the actual information to be archived, and associated meta data that describes the archived information.
maint and constr resource request Request for road maintenance and construction resources that can be used in the diversion of traffic (cones, portable signs), clearance of a road hazard, repair of ancillary damage, or any other incident response. The request may poll for resource availability or request pre-staging, staging, or immediate dispatch of resources.
maint and constr resource response Current status of maintenance and construction resources including availability and deployment status. General resource inventory information covering vehicles, equipment, materials, and people and specific resource deployment status may be included.
maint and constr work plans Future construction and maintenance work schedules and activities including anticipated closures with anticipated impact to the roadway, alternate routes, anticipated delays, closure times, and durations.
parking demand management request Request to change the demand for parking facility use through pricing or other mechanisms.
parking demand management response Response to parking demand management change requests indicating level of compliance with request.
parking information General parking information and status, including current parking availability.
parking lot data request Request for parking lot occupancy, fares, and availability. The request can be a subscription that initiates as-needed information updates as well as a one-time request for information.
payment Payment of some kind (e.g., toll, parking, fare) by traveler which, in most cases, can be related to a credit account.
qualified environmental conditions data Current road conditions (e.g., surface temperature, subsurface temperature, moisture, icing, treatment status) and surface weather conditions (e.g., air temperature, wind speed, precipitation, visibility) that has had quality checks performed on it and has been formatted and consolidated by the Clarus system. Attributes relating to the data collection (and aggregation) are also included.
remote vehicle disable Signal used to remotely disable a transit vehicle.
request for payment Request to deduct cost of service from user's payment account.
request for vehicle measures Request for vehicle performance and maintenance data collected by onboard sensors.
request transit information Request for transit service information and current transit status.
resource coordination Coordination of resource inventory information, specific resource status information, resource prioritization and reallocation between jurisdictions, and specific requests for resources and responses that service those requests.
resource deployment status Status of resource deployment identifying the resources (vehicles, equipment, materials, and personnel) available and their current status. General resource inventory information and specific status of deployed resources may be included.
resource request A request for resources to implement special traffic control measures, assist in clean up, verify an incident, etc. The request may poll for resource availability or request pre-staging, staging, or immediate deployment of resources. Resources may be explicitly requested or a service may be requested and the specific resource deployment may be determined by the responding agency.
reversible lane control Control of automated reversible lane configuration and driver information systems.
reversible lane status Current reversible lane status including traffic sensor and surveillance data and the operational status and mode of the reversible lane control equipment.
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 architecture 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 along with a definition of the links, nodes, and routes that make up the road network.
road network traffic probe data Aggregated route usage, travel times, and other aggregated data collected from probe vehicles that can be used to estimate current traffic conditions.
road user protection data Current data as well as operational status from mixed roadway and right-of-way systems.
road user protection device control Control requests and operating parameters for mixed roadway and right-of-way systems.
road weather information Road conditions and weather information that are made available by road maintenance operations to other transportation system operators.
roadway equipment coordination The direct flow of information between field equipment. This includes transfer of information between sensors and driver information systems (e.g., DMS, HAR, variable speed limit signs, dynamic lane signs) or control devices (e.g., traffic signals, ramp meters), direct coordination between adjacent control devices, interfaces between detection and warning or alarm systems, and any other direct communications between field equipment.
roadway information system data Information used to initialize, configure, and control roadside systems that provide driver information (e.g., dynamic message signs, highway advisory radio, beacon systems). 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 systems.
roadway information system status Current operating status of dynamic message signs, highway advisory radios, beacon systems, or other configurable field equipment that provides dynamic information to the driver.
roadway maintenance status Summary of maintenance fleet operations affecting the road network. This includes the status of winter maintenance (snow plow schedule and current status).
roadway warning system control Information used to configure and control roadway warning systems.
roadway warning system status Current operating status of roadway warning systems.
secure area surveillance control Information used to configure and control audio and video surveillance systems used for transportation infrastructure security in secure areas. The provided information controls surveillance data collection, aggregation, filtering, and other local processing.
secure area surveillance data Data collected from surveillance systems used to monitor secure areas. Includes video, audio, processed surveillance data, equipment operational status, and alarm indicators when a threat has been detected.
selected routes Routes selected based on route request criteria.
shoulder management control Information used to configure and control systems that allow use of a shoulder as a lane for vehicular traffic.
shoulder management information System status including current operational state, violations and logged information.
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 from traffic signal control equipment.
speed monitoring control Information used to configure and control automated speed monitoring, speed warning, and speed enforcement systems.
speed monitoring information System status including current operational state and logged information including measured speeds, warning messages displayed, and violation records.
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.
threat information Threats regarding transportation infrastructure, facilities, or systems detected by a variety of methods (sensors, surveillance, threat analysis of advisories from outside agencies, etc.
threat information coordination Sensor, surveillance, and threat data including raw and processed data that is collected by sensor and surveillance equipment located in secure areas.
track status Current status of the wayside equipment and notification of an arriving train.
traffic archive data Information describing the use and vehicle composition on transportation facilities and the traffic control strategies employed. Content may include a catalog of available information, the actual information to be archived, and associated meta data that describes the archived information.
traffic characteristics Physical traffic characteristics which are monitored and translated into macroscopic measures like occupancy, volume, density, and average speed. Point measures support presence detection and individual vehicle measures like speed.
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).
traffic flow Raw and/or processed traffic detector data which allows derivation of traffic flow variables (e.g., speed, volume, and density measures) and associated information (e.g., congestion, potential incidents). This flow includes the traffic data and the operational status of the traffic detectors.
traffic images High fidelity, real-time traffic images suitable for surveillance monitoring by the operator or for use in machine vision applications.
traffic metering control Control commands and operating parameters for ramp meters, interchange meters, mainline meters, and other systems equipment associated with roadway metering operations.
traffic metering status Current operational status and operating parameters for ramp meters, interchange meters, mainline meters and other control equipment associated with roadway metering operations.
traffic probe data Vehicle data that is used to determine traffic conditions. In a basic implementation, the data could be limited to time stamped unique identifiers that can be used to measure a vehicle’s progress through the network. In more advanced implementations, the vehicle may report current position, speed, and heading and snapshots of recent events including route information, starts and stops, speed changes, and other information that can be used to estimate traffic conditions.
traffic sensor control Information used to configure and control traffic sensor systems.
transit and fare schedules Transit service information including routes, schedules, and fare information.
transit archive data Data used to describe and monitor transit demand, fares, operations, and system performance. Content may include a catalog of available information, the actual information to be archived, and associated meta data that describes the archived information.
transit demand management request Request to change the demand for transit facility use through pricing or other mechanisms.
transit demand management response Response to transit demand management change requests indicating level of compliance with request.
transit emergency data Initial notification of transit emergency at a transit stop or on transit vehicles and further coordination as additional details become available and the response is coordinated.
transit fare and passenger status Information provided from the traveler location that supports fare payments, passenger data, and associated record-keeping.
transit fare information Information provided by transit management that supports fare payment transactions and passenger data collection.
transit incident information Information on transit incidents that impact transit services for public dissemination.
transit information request Request for transit operations information including schedule and fare information. The request can be a subscription that initiates as-needed information updates as well as a one-time request for information.
transit information user request Request for special transit routing, real-time schedule information, and availability information.
transit probe data Aggregate probe data derived from tracking transit vehicles. Data collected could include transit vehicle speeds and travel times for a given link or collection of links.
transit schedule adherence information Dynamic transit schedule adherence and transit vehicle location information.
transit schedule information Current and projected transit schedule information used to initialize the transit vehicle with a vehicle assignment, monitor schedule performance, and develop corrective actions on-board.
transit service coordination Schedule coordination information shared between local/regional transit organizations.
transit system data Current transit system operations information indicating current transit routes, the level of service on each route, and the progress of individual vehicles along their routes for use in forecasting demand and estimating current transportation network performance.
transit traveler information Transit information prepared to support transit users and other travelers. It contains transit schedules, real-time arrival information, fare schedules, alerts and advisories, and general transit service information.
transit traveler request Request by a Transit traveler to summon assistance, request transit information, or request any other transit services.
transit trip plan An origin-destination transit trip that may involve multiple modes and connections. (could use current trip plan that is PIAS to ISP, but since this is center to center a separate AF might be called for).
transit trip request Request for a transit trip plan that is responsive to traveler requirements such as schedule, cost, or duration.
transit user information Information about individual transit users boarding a transit vehicle, used to track a user's progress on a scheduled transit trip.
transit vehicle conditions Operating conditions of transit vehicle (e.g., engine running, oil pressure, fuel level and usage).
transit vehicle loading data Data collected on board the transit vehicle relating to passenger boarding and alighting.
transit vehicle location data Current transit vehicle location and related operational conditions data provided by a transit vehicle.
transit vehicle operator authentication information Information regarding on-board transit operator authentication
transit vehicle operator authentication update Results of authentication process or update of on-board authentication database.
transit vehicle operator information Transit service instructions, wide area alerts, traffic information, road conditions, and other information for both transit and paratransit operators.
transit vehicle operator information to center_ud Transit service confirmation, traffic information, road conditions, and other information from both transit and paratransit operators.
transit vehicle schedule performance Estimated times of arrival and anticipated schedule deviations reported by a transit vehicle.
transportation system status Current status and condition of transportation infrastructure (e.g., tunnels, bridges, interchanges, TMC offices, maintenance facilities). In case of disaster or major incident, this flow provides an assessment of damage sustained by the surface transportation system including location and extent of the damage, estimate of remaining capacity and necessary restrictions, and time frame for repair and recovery.
travel time data_ud Trip and travel time information.
traveler archive data Data associated with traveler information services including service requests, facility usage, rideshare, routing, and traveler payment transaction data. Content may include a catalog of available information, the actual information to be archived, and associated meta data that describes the archived information.
traveler information for media General traveler information regarding incidents, unusual traffic conditions, transit issues, or other advisory information that has been desensitized and provided to the media.
traveler profile Information about a traveler including equipment capabilities, personal preferences, and traveler alert subscriptions.
traveler request A request for traveler information including traffic, transit, toll, parking, road weather conditions, event, and passenger rail information. The request identifies the type of information, the area of interest, parameters that are used to prioritize or filter the returned information, and sorting preferences.
trip plan A travel itinerary identifying a route and associated traveler information and instructions identifying recommended modes and transfer information, ride sharing options, and transit and parking reservation information.
trip request Request for trip planning services that identifies the trip origin, destination(s), timing, preferences, and constraints. The request may also include a request for transit and parking reservations and ridesharing options associated with the trip.
variable speed limit control Information used to configure and control variable speed limit systems including the equipment used to provide current speed limits and other information to drivers and the equipment used to monitor traffic and environmental conditions along the roadway.
variable speed limit status Current operating status of the variable speed limit systems including the state of the equipment.
video surveillance control Information used to configure and control video surveillance systems.
weather information Accumulated forecasted and current weather data (e.g., temperature, pressure, wind speed, wind direction, humidity, precipitation, visibility, light conditions, etc.).
work plan coordination Coordination of work plan schedules and activities between maintenance and construction organizations or systems. This information includes the work plan schedules and comments and suggested changes that are exchanged as work plans are coordinated and finalized.
work plan feedback Comments and suggested changes to proposed construction and maintenance work schedules and activities. This information influences work plan schedules so that they minimize impact to other system operations and the overall transportation system.
work zone information Summary of maintenance and construction work zone activities affecting the road network including the nature of the maintenance or construction activity, location, impact to the roadway, expected time(s) and duration of impact, anticipated delays, alternate routes, and suggested speed limits. This information may be augmented with images that provide a visual indication of current work zone status and traffic impacts.
work zone warning status Status of a work zone safety monitoring and warning devices. This flow documents system activations and includes additional supporting information (e.g., an image) that allows verification of the alarm.

Last updated: 06-23-13