310 likes | 451 Views
TSIP: Real Time Situational Status Profile. Real Time & Service RSTWG 23 September 2009. Discussion Items. Context for Real Time SDP Extension Real Time Status “Profile” / “Method” Needs Architecture and Data Flows Existing APIs TriMet MTC Methods and Context / Sequence Diagrams.
E N D
TSIP: Real Time Situational Status Profile Real Time & Service RSTWG 23 September 2009
Discussion Items • Context for Real Time SDP Extension • Real Time Status “Profile” / “Method” Needs • Architecture and Data Flows • Existing APIs • TriMet • MTC • Methods and Context / Sequence Diagrams
TSIP Project Purpose “a framework to provide a single point of storage, discovery, and access to a variety of transit service information and tools” Including Real Time Situational Status Information And the Transit Service Data that supports Real Time data
Task 2: SDP Extensions • Planning Data • Real Time / Status Data • Fare Data • Task 3: TSIP Requirements • Task 4: External TSIP Requirements • Task 5: Procurement Approach Task & Schedule Task 2 & 3 – 11 Months Task 4 – about Month 6 Task 5 – 11th Month
Real-Time Status Extension – RT TWG (Tasks and Deliverables) White paper: -- Industry scan: Issues, architectures, standards -- Survey on Situational Data Needs for region
“Situational Status” Definition Estimated impact (estimated arrival, estimated departure, schedule adherence, etc.) on actual service at a transit stop.
Real Time Status “Profile” Needs • Efficiently gather, process, and disseminate real time status information and deliver it to the customer. • Ensure that the dissemination method (syntax, semantics and encoding) specified uses conventional and industry-accepted standards or specifications. The semantics should conform to the current version of the SDP functional requirements. • Provide transit operator current status information that meets downstream customer information needs (see Table 1 below)
Real Time Status “Profile” Needs • Provide and identify quality and descriptive information about real time status • Ensure the logical consistency of the data in the Real Time Status “method” (RTSM) • Ensure data persistence or access to references included in the RTSM • Ensure the quality data is incorporated into the RTSM.
Real Time Status “Method” Needs • Method descriptions should • support request/response (one time), stored request/response, and subscription request/response capabilities • be structured as “elemental” requests and developed to be “chained” into more complex requests • support error handling and processing • be extensible and easy to maintain. • be extensible and easy to convert to other channel encoding formats
TSIP Integration Model: Centralized Approach • Transfer “AVL” Locations • (TrMS to TSIP via RT Application) • Current (persistent) Daily operator status • (TrMS to TSIP via SDP) • API for Data Consumer Access • (TSIP to Traveler)
Transfer “AVL” Locations TrMS to TSIP via RT Application
“AVL” Location Data Needs • Information should include: • Current Location (spatial, distance traveled along route configuration, heading, speed-avg, other public information) • Updated Route Configuration (block for bus, layovers, pattern, running times, dwell times, etc. or changes to scheduled route configuration) • Updated system detour and disruption information (congestion along tracks going into station, fire in tunnel, detour route for bus due to construction, etc.) • Performance requirements • Frequency, file size, quality measures
API for Data Consumer Access TSIP to Traveler
TriMet Methods • Request AppID
TriMet Arrivals API Request: up to 10 location identifiers, each associated with a transit stop (in a comma delimited list). resultSet includes -- attribute (queryTime) -- errorMessage -- location -- arrival -- routeStatus
Arrivals resultSet for “6849” & “6850” <?xml version="1.0" encoding="UTF-8"?> <resultSetxmlns="urn:trimet:arrivals" queryTime="1249652690996"> <locationdesc="SE 17th & Center" dir="Northbound" lat="45.4935714921804" lng="-122.64825645346" locid="6849"/> <locationdesc="SE 17th & Center" dir="Southbound" lat="45.4942619500587" lng="-122.64841793104" locid="6850" /> …. <arrivalblock="1708“ departed="true" dir="0“ estimated="1249654360000“ fullSign="17 Holgate to 136th Ave“ piece="1“ route="17“ scheduled="1249654380000“ shortSign="17 To 136th Ave“ status="estimated“ locid="6850“ detour="false"> <blockPositionat="1249652656000“ feet="27670“ heading="177“ lat="45.5309937“ lng="-122.6945941"> <tripdesc="Holgate & 134th Dr" destDist="65898“ dir="0“ pattern="1“ progress="38228“ route="17“ tripNum="1060" /> </blockPosition> </arrival> </resultSet> Note: API supports stop and route persistence
Response to GetDepartureTimeList <?xml version="1.0" encoding="utf-8" ?> <departureTimeList> <stop name="19th St. Oakland" stopID="73214" routeName="RICHMOND | A“> <departureTime>7</departureTime> <departureTime>10</departureTime> <departureTime>14</departureTime> </stop> </departureTimeList> MTC API: GetDepartureTimeList() Request: -- agency (GetAgencyList), -- route (GetRouteList), -- stop (GetStopList) Response: “GetDepartureTimeList retrieves a list of departure times for a given list of stop IDs. Each departure time is represented by an integer minutes value.”
Current Daily Operator Status TrMS to TSIP via SDP
Current Daily Operator Status Data Needs • Special service • Can the SDP revision element support this requirement? • Actual detours and disruptions to regular service and stop/station (including parking) • Changes to schedule -- Ad Hoc Schedule in the form of SDP Revision • For Buses: including Block information, information for public (e.g., headsign, bus ID) • For Trains: number of cars, etc. • Changes to Stops and Stations Configuration • E.g., Portal closed, stop under construction, platform supports only first two cars in consis…
Errors & Exceptions Methods and Messages
Errors and ExceptionsPotential error messages from TCIP 3.0.2 nullData (1), intentionalBlank (2), deletedByDevice (3), msgUnavailable (4), illegalCalc (5), deviceMalfunction (6), msgExpired (7), suppressedSecurity (8), suppressedPrivacy (9), unspecified (10), vehicle Shutdown (11), unknownFile (12), receiverCantProcess(13), incompleteMessage (14), fileCorrupt (15), invalidPriority (51), invalidFrequency (52), invalidMode (53), invalidDeliveryVerification (54), cantDecrypt (55), accessDenied (56), excessLatency (57), invalidMsgRef (58), timeExpired (59), dataUnavailable (60), dataExpired (61), valueOutOfRange (62)
Detour and Disruption Information TRMS to TSIP Detours/ Disruptions
Disruption Information Needs Severity, security, privacy Disruption Type Description Passenger mitigation procedures Passenger instructions for alternate transportation Impact to other routes/lines Time disruption occurred Estimated time to complete mitigation, response, recovery
Detour Information Needs Use SDP with Revision as Ad Hoc Schedule
Data Quality Measures
Next Steps • Agree on data requirements and exchange procedures (will post early Nov on wiki) • UML Class Diagram and Definitions • UML Context and Sequence Diagrams and descriptions • Develop Requirements Document -- composed of API descriptions in XML (due early Dec – will post on wiki) • XML Schema • Plain Old XML (POX) • REST • Or other format