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Architecture Flows

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Architecture Flow Architecture Flow Description
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.
archive analysis requests A user request that initiates data mining, analytical processing, aggregation or summarization, report formulation, or other advanced processing and analysis of archived data. The request also includes information that is used to identify and authenticate the user and support electronic payment requirements, if any.
archive analysis results Processed information products, supporting meta data, and any associated transaction information resulting from data mining, analytical processing, aggregation or summarization, report formulation, or other on-line processing and analysis of archived data.
archive coordination Catalog data, meta data, published data, and other information exchanged between archives to support data synchronization and satisfy user data requests.
archive request confirmation Confirmation that an archive request has been received and processed with information on the disposition of the request.
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.
archived data products Raw or processed data, meta data, data catalogs and other data products provided to a user system upon request. The response may also include any associated transaction information.
bad tag list List of invalid transit user tags which may have previously failed a fare payment transaction.
broadcast information General broadcast information that contains link travel times, incidents, advisories, transit services and a myriad of other traveler information.
care facility status Information regarding facility type and capabilities, facility status, and its ability to admit new patients.
care facility status request Request for information regarding care facility availability and status.
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.
data collection and monitoring control Information used to configure and control data collection and monitoring systems.
demand responsive transit plan Plan regarding overall demand responsive transit schedules and deployment.
demand responsive transit request Request for paratransit support.
E 9-1-1 PSAP data_ud
E 9-1-1 system administration data_ud
emergency acknowledge Acknowledge request for emergency assistance and provide additional details regarding actions and verification requirements.
emergency ackownledge_ud
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 (e.g., a suggested route) and provision of en route status.
emergency notification An emergency request for assistance originated by a traveler using an in-vehicle, public access, or personal device or originated by a transit vehicle operator using an on-board device.
emergency notification_ud
emergency plan coordination Information that supports coordination of emergency management plans, continuity of operations plans, emergency response and recovery plans, evacuation plans, and other emergency plans between agencies. This includes general plans that are coordinated prior to an incident and shorter duration tactical plans that are prepared during an incident.
emergency resource request_ud
emergency resource response_ud
emergency traffic control information Status of a special traffic control strategy or system activation implemented in response to an emergency traffic control request, a request for emergency access routes, a request for evacuation, a request to activate closure systems, a request to employ driver information systems to support public safety objectives, or other special requests. Identifies the selected traffic control strategy and system control status.
emergency traffic control request Special request to preempt the current traffic control strategy in effect at one or more signalized intersections or highway segments, activate traffic control and closure systems such as gates and barriers, activate safeguard systems, or use driver information systems. For example, this flow can request all signals to red-flash, request a progression of traffic control preemptions along an emergency vehicle route, request a specific evacuation traffic control plan, request activation of a road closure barrier system, or place a public safety or emergency-related message on a dynamic message sign.
emergency transit schedule information Information on transit schedule and service changes that adapt the service to better meet needs of responders and the general public in an emergency situation, including special service schedules supporting evacuation.
emergency transit service request Request to modify transit service and fare schedules to address emergencies, including requests for transit services to evacuate people from and/or deploy response agency personnel to an emergency scene. The request may poll for resource availability or request pre-staging, staging, or immediate dispatch of transit resources.
emergency transit service response Response indicating changes to transit service, fares, and/or restrictions that will be made and status of transit resources to be deployed to support emergency response and/or evacuation.
emergency vehicle tracking data The current location and operating status of the emergency vehicle.
equipment maintenance status Current status of field equipment maintenance actions.
evacuation coordination Coordination of information regarding a pending or in-process evacuation. Includes evacuation zones, evacuation times, evacuation routes, forecast network conditions, and reentry times.
evacuation information Evacuation instructions and information including evacuation zones, evacuation times, and reentry times.
event plans Plans for major events possibly impacting traffic.
fare and payment status Current fare collection information including the operational status of the fare collection equipment and financial payment transaction data.
field device status Reports from field equipment (sensors, signals, signs, controllers, etc.) which indicate current operational status.
field equipment status Identification of field equipment requiring repair and known information about the associated faults.
hazmat information Information about a particular hazmat load including nature of the load and unloading instructions. May also include hazmat vehicle route and route update information.
hazmat information request Request for information about a particular hazmat load.
hazmat spill notification This data flow is used by the on-board cargo monitoring equipment package to contact emergency response organizations when the cargo sensors detect a release of hazardous material. This information will include the vehicle location discussed above as well as identifying the carrier. The information may be provided as a response to a real-time query or proactively by the source. The query flow is not explicitly shown.
hri advisories Notification of Highway-Rail Intersection equipment failure, intersection blockage, or other condition requiring attention, and maintenance activities at or near highway rail intersections.
hri control data Data required for HRI information transmitted at railroad grade crossings and within railroad operations.
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 request A request for highway-rail intersection status or a specific control request intended to modify HRI operation.
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.
incident information for media Report of current desensitized incident information prepared for public dissemination through the media.
incident information for rail_ud
incident notification The notification of an incident including its nature, severity, and location.
incident notification response Interactive acknowledgement and verification of the incident information received, requests for additional information, and general information on incident response status.
incident report 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 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.
ISP coordination Coordination and exchange of transportation information between centers. This flow allows a broad range of transportation information collected by one ISP to be redistributed to many other ISPs and their clients.
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 dispatch information Information used to dispatch maintenance and construction vehicles, equipment, and crews and information used to keep work zone crews informed. This information includes routing information, traffic information, road restrictions, incident information, environmental information, decision support information, maintenance schedule data, dispatch instructions, personnel assignments, alert notifications, and corrective actions.
maint and constr dispatch status Current maintenance and construction status including work data, operator status, crew status, and equipment status.
maint and constr resource coordination 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.
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 vehicle conditions Vehicle diagnostics information that is collected, filtered, and selectively reported by a maintenance and construction vehicle. The information includes engine temperature, mileage, tire wear, brake wear, belt wear, and any warnings or alarms concerning the operational condition of the vehicle and ancillary equipment.
maint and constr vehicle location data The current location and related status (e.g., direction and speed) of the maintenance/construction vehicle.
maint and constr vehicle operational data Data that describes the maintenance and construction activity performed by the vehicle. Operational data includes materials usage (amount stored and current application rate), operational state of the maintenance equipment (e.g., blade up/down, spreader pattern), vehicle safety status, and other measures associated with the operation of a maintenance, construction, or other special purpose vehicle. Operational data may include basic operational status of the vehicle equipment or a more precise record of the work performed (e.g., application of crack sealant with precise locations and application characteristics).
maint and constr vehicle system control Configure and control data that supports remote control of on-board maintenance and construction vehicle systems and field equipment that is remotely controlled by the vehicle. For example, the data can be used to adjust material application rates and spread patterns.
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.
multimodal service data Multimodal transportation schedules and other service information.
parking coordination_ud
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 equipment control_ud
parking equipment status_ud
parking information General parking information and 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.
passenger data and use_ud
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.
payment Payment of some kind (e.g., toll, parking, fare) by traveler which, in most cases, can be related to a credit account.
payment request Request for payment from financial institution.
rail incident information_ud
rail incident response status Status of the rail systemís response to current incidents.
railroad advisories Real-time notification of railway-related incident or advisory.
railroad schedules Train schedules, maintenance schedules, and other information from the railroad that supports forecast of HRI closures.
remote surveillance control The control commands used to remotely operate another center's sensors or surveillance equipment so that roadside surveillance assets can be shared by more than one agency.
request for right-of-way Forwarded request from signal prioritization, signal preemption, pedestrian call, multi-modal crossing activation, or other source for right-of-way.
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 deployment status Status of traffic management 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 traffic management 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.
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.
road network conditions Current and forecasted traffic information, road and weather conditions, traffic incident information, 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 also included.
road weather information Road conditions and weather information that are made available by road maintenance operations to other transportation system operators.
road weather information_ud
roadside archive data A broad set of data derived from roadside sensors that includes current traffic conditions, environmental conditions, and any other data that can be directly collected by roadside sensors. This data also indicates the status of the sensors and reports of any identified sensor faults.
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).
secure area sensor control Information used to configure and control threat sensors (e.g., thermal, acoustic, radiological, chemical), object, motion and intrusion detection sensors. The provided information controls sensor data collection, aggregation, filtering, and other local processing.
secure area sensor data Data provided by threat sensors (e.g., thermal, acoustic, radiological, chemical), and intrusion, motion, and object detection sensors in secure areas indicating the sensor's operational status, raw and processed sensor data, and alarm indicators when a threat has been detected.
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.
signal control data Information used to configure and control traffic signal systems.
signal control status Status of surface street signal controls.
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.
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 control coordination Information transfers that enable remote monitoring and control of traffic management devices. This flow is intended to allow cooperative access to, and control of, field equipment during incidents and special events and during day-to-day operations. This flow also allows 24-hour centers to monitor and control assets of other centers during off-hours, allows system redundancies and fail-over capabilities to be established, and otherwise enables integrated traffic control strategies in a region.
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).
traffic images High fidelity, real-time traffic images suitable for surveillance monitoring by the operator or for use in machine vision applications. This flow includes the images and the operational status of the surveillance system.
traffic information coordination Traffic information exchanged between TMCís. Normally would include incidents, congestion data, traffic data, signal timing plans, and real-time signal control information.
traffic sensor control Information used to configure and control traffic sensor systems.
transaction status Response to transaction request. Normally dealing with a request for payment.
transit and fare schedules Transit service information including routes, schedules, schedule adherence, and fare information. Includes transit service information during evacuation.
transit and fare schedules_ud
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 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 multimodal information Transit schedule information for coordination at modal interchange points.
transit schedule information Current and projected transit schedule adherence.
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 vehicle conditions Operating conditions of transit vehicle (e.g., engine running, oil pressure, or mileage).
transit vehicle location data Current transit vehicle location and related operational conditions data provided by a transit vehicle.
transit vehicle operator authentication update Results of authentication process or update of on-board authentication database.
transit vehicle operator instructions Transit service instructions, traffic information, road conditions, and other information for both transit and paratransit operators.
transit vehicle passenger and use data Data collected on board the transit vehicle pertaining to availability and/or passenger count.
transit vehicle schedule performance Estimated times of arrival and anticipated schedule deviations reported by a transit vehicle.
travel service information Information supplied by a service provider (e.g., a hotel or restaurant) that identifies the service provider and provides details of the service offering. This flow covers initial registration of a service provider and subsequent submittal of new information and status updates so that data currency is maintained.
travel service information request Requests for travel service information. This flow supports initial registration of service providers and requests for additional traveler service information from registered providers.
travel service reservation request Reservation request for traveler services (e.g. for a hotel or restaurant) including billing information when applicable.
travel service reservations Traveler service (e.g., for a hotel or restaurant) reservation information and status, including information on associated billing transactions, when applicable.
traveler card information The traveler personal information such as name, address, license number, and trip records and profile data.
traveler card update Information updated concerning traveler's personal data including items such as address, trip records, and profile data.
traveler information Traveler information comprised of traffic and road conditions, advisories, incidents, payment information, transit services, and many other travel-related data updates and confirmations.
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 recurring trip characteristics.
traveler request Request by a traveler to summon assistance, request information, make a reservation, or initiate any other traveler service.
trip confirmation Acknowledgement by the driver/traveler of acceptance of a route.
trip plan A sequence of links and special instructions comprising of a trip plan indicating efficient routes for navigating the links. Normally coordinated with traffic conditions, other incidents, preemption and prioritization plans.
trip request Request by a driver/traveler for special routing.
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 plans_ud
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 status Current work zone status including current location (and future locations for moving work zones), impact to the roadway, required lane shifts, expected time(s) and duration of impact, anticipated delays, alternate routes, and suggested speed limits.
yellow pages information Travel service information covering tourist attractions, lodging, restaurants, service stations, emergency services, and other services and businesses of interest to the traveler.
yellow pages request Request for information through a yellow pages type service.

Last updated: 04-22-05