real time & service rstwg 23 september 2009 tsip: real time situational status profile
TRANSCRIPT
REAL TIME & SERVICE RSTWG23 SEPTEMBER 2009
TSIP: Real Time Situational Status Profile
Discussion Items
Context for Real Time SDP ExtensionReal Time Status “Profile” / “Method” NeedsArchitecture and Data FlowsExisting APIs
TriMet MTC
Methods and Context / Sequence Diagrams
“ A F R A M E W O R K T O P R OV I D E A S I N G L E P O I N T O F S T O R A G E , D I S C OV E RY, A N D A C C E SS T O A VA R I E T Y O F T R A N S I T S E RV I C E I N F O R M AT I O N A N D T O O L S ”
I N C LU D I N G
R E A L T I M E S I T UAT I O N A L S TAT U S I N F O R M AT I O NA N D T H E
T R A N S I T S E RV I C E D ATA T H AT S U P P O RT S R E A L T I M E D ATA
TSIP Project Purpose
Task & Schedule
Task 2 & 3 – 11 Months
Task 4 – about Month 6
Task 5 – 11th Month
Task 2: SDP Extensions Planning Data Real Time / Status Data Fare Data
Task 3: TSIP RequirementsTask 4: External TSIP
RequirementsTask 5: Procurement
Approach
Real-Time Status Extension – RT TWG (Tasks and Deliverables)
Input to TSIP Concept of
Operations
Architecture, Needs and 3 Use Case Topics
Functional/Data Requirements Document
(i) Real-time data from
Providers(2) Web Service
Typical Prediction Use Case
Incident/Disruption Use Case
Regional Transfer Scenario Use Case
Specifications for Web Services / Application
Programming Interfaces (APIs)
Demonstration(Technical Support)
Validate SDP XML Documents with Downstream Applications
Final Deliverables
(1) SDP Guidance Documents(2) SDP XML Schema and Web Service (final)
(3) Updated Functional Requirements Document & Conceptual Data Reference Model
TBD
White paper:-- Industry scan: Issues, architectures, standards-- Survey on Situational Data Needs for region
TSIP Project Systems Engineering Approach
Concept of Operationsfor
Regional Service Data Repository & Portal
(includes TSDEA Use Cases, Portal and SDP Extension
UC)
System RequirementsFor
TSIP Implementation Includes family of SDP data models and XML Schema
Trip Planning Use Cases & ConOps Addendum
RT Status Use Case
Fare Calculator Use Case
SDP, Calendar and Extension XML Schema &
open source code
Specifications and Request for Proposal
Final Deliverables
(1) SDP and Extension Guidance Documents(2) SDP XML Schemas(3) Requirements Document & Conceptual Data Reference Models for all SDP / SDP Extensions(4) Demonstration results (conversion software from native Agency data to SDP to downstream applications)
SDP / SDP Extension Requirements
Portal Use Cases
SDP Extensions
“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)
TRMS TO TSIP VIA RT APPLICATION
Transfer “AVL” Locations
“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
TSIP TO TRAVELER
API for Data Consumer Access
TriMet Methods
API Description
Arrivals:Reports next arrivals at a stop identified by location ID.
Detours:Retrieves a list of detours currently in effect by route.
RouteConfig:
Retrieves a list of routes being reported by TransitTracker from the active schedule, optionally a list of directions for those routes and stops in each of those directions.
Trip Planner:Plan trips between two locations programmatically.
• 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"?><resultSet xmlns="urn:trimet:arrivals" queryTime="1249652690996">
<location desc="SE 17th & Center" dir="Northbound" lat="45.4935714921804" lng="-122.64825645346" locid="6849" />
<location desc="SE 17th & Center" dir="Southbound" lat="45.4942619500587" lng="-122.64841793104" locid="6850" />….<arrival block="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"> <blockPosition at="1249652656000“ feet="27670“ heading="177“ lat="45.5309937“ lng="-122.6945941">
<trip desc="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
MTC “My 511” Methods
Service Name Category EndPoint DescriptionGetToken Security Transit.asmx Retrieves a security token for use with service
calls. (Planned)
GetVersion System Transit.asmx Retrieves the version of the service endpoint.
GetAgencyList Transit Transit.asmx Retrieves a list of the transit agencies in the MY 511 system.
GetDeparuteTimeList Transit Transit.asmx Retrieves a list of departure times for a given set of stop IDs.
GetDirectionList Transit Transit.asmx Retrieves a list of direction entries for an agency that supports direction information.
GetRouteList Transit Transit.asmx Retrieves a list of routes for a given agency.
GetStopList Transit Transit.asmx Retrieves a list of transit stops for a given route.
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.”
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>
SDP Real Time API Data Needs
Needs MTC / TriMet
Authorized User GetToken / request AppID via email
Agency Information GetAgencyList (no mixed status information messages) / not applicable (NA)
Service & Route Information GetDirectionList; GetRouteList; GetStopList / RouteConfigNote: MTC only includes stopIDs near requested intersection; no spatial reference information
Real Time Status (departure, arrivals, disruptions)
GetDepartureTimeList – by route & stop (no disruption information) / Arrivals by stop; Detours
Quality Information NA/ attribute = query time
Estimated Travel Time Not Available
Specific “train” information Not Available
Errors / Exceptions Included in both
Schedule Adherence or raw locations
No / may be derived* from Arrival@block
Supports Multiple Routes at a “Stop”
TRMS TO TSIP VIA SDP
Current Daily Operator Status
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…
METHODS AND MESSAGES
Errors & Exceptions
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)
TRMS TO TSIP
Detour and Disruption Information
Detours/Disruptio
ns
Disruption Information Needs
Severity, security, privacyDisruption TypeDescriptionPassenger mitigation proceduresPassenger instructions for alternate
transportationImpact to other routes/linesTime disruption occurredEstimated time to complete mitigation,
response, recovery
Detour Information Needs
Use SDP with Revision as Ad Hoc Schedule
MEASURES
Data Quality
Real Time Quality Measures
Quality Types Measure
Temporal (customer access API)
Published (valid, query time)RefreshedUpdated
Tracking(AVL location informati0n)
Accuracy and type of Sensor-- GPS-- dead reckoning and system clock
Frequency of updates
Detour and disruption information
Start timeLast update
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