© 2004Kizoom

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Structured Travel Incidents & Situations

SIRI - Service Interface for Real Time

Information (CEN-OO278181 )

http://www.siri.org.uk

CENTC278 WG3

27- 29 Cursitor StreetLondon, EC4A 1LT

nick_knowles@kizoom.com

Siri 0.1g v3.6c

© 2004Kizoom

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Topics

• SIRI

• UK Guidance

• Possible Further CEN Work Items– Additional Functional Services

• Further convergence / interoperability– TIH, Datex ?

© 2004Kizoom

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SIRI Structured Incidents - Rationale

• SIRI GMS is currently agnostic on incident structure.– Can embed any message structure – But Can’t relate incident content to SIRI functional service payload / location

model • Want a richer semantics

• Need to choose an incident structure model– TPEG is popular standard for PT & ROAD incidents, with TpegML – Has message identity management suitable for distributed model– Has systematic classification scheme of causes & effects– Has NL translations

• Why not just use TPEG as it is? – Function

• Is missing some function e.g.control action and distribution data that experience shows we need

– Technology • Predates TransModel –• Model derived from binary optimised form – complex rules to endcode/decode• DTD based

– Process

© 2004Kizoom

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Structured Situations - Concept

– XML schema designed with semantics tied to SIRI model & other functional services

• Effects / Location Model• Control Actions: eg cancellation, addition, short working• Equipment

– TransModel concepts and termonology– Full TPEG interoperability : can translate into /out of

TPEG, retaining message identity– Exchange with GMS

• Other services use existing support for Situation References

© 2004Kizoom

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Distributed Computerised Incident Processing

7 56

121110

8 4

21

9 3

Line, Section, Station, AreaReason, Severity

Start, End, Duration/ Expiry

Trackable : Timestamp, Id, Cross-references

Actions, Channels, Workgroups, etc

Summary, Detail

Summary, Detail

AdvisoryAdvisory

Computer-generated, computer readable

Human readable

Effect

• Processing by Computers– XML & other renderings

• Presenting to Humans – Multi-channel delivery

• Incident is self describing object

• Rich Structured Model– Identity Management– Standards based Classification– Standards based Location

Model– Distribution Actions & directives– Quality data

• Many Distribution “Rules Engine” Business Rules Relate to This Model

© 2004Kizoom

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Distributed Message (ie Incident) Management

Applications

IncidentDatabase

Interface

Applications

IncidentDatabase

Interface

Applications

IncidentDatabase

Interface

Applications

IncidentDatabase

Interface

Applications

IncidentDatabase

Interface

•Solution Architecture•Store & Forward•Write only + Cross-reference •XML Exchange Interface•Interface versioning•Structured Distribution rules

Life Cycle Events•New message•Publish message•Update to message•Expiry of message

•Challenges•Many different participants & sources•Heterogeneous systems•Multi-way flow•Real time, mission critical •Many point of failure

© 2004Kizoom

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The Incident Lifecycle • All participants need to apply the

same rules to incidents – E.g. How long valid, precedence of

update, location model interpretation.

– Identity & version management rules allow reconciliation of updates

– State Model incident describes allowed states and transitions.

• Eg once published must be closed

– Cross referencing allows linking of independent into causal chains

© 2004Kizoom

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Situation Contents

• Message Identity– Identity & version– Cross reference

• Message Content– Status– Temporal Scope– Classification: TPEG – Textual Descriptions (where different from derived)– Network Scope (Affects)

• Location Model: Lines, VehicleJourneys, StopPoints, Operators– Resulting Disruption (Effects)

• Location Model• Delays, Mobility, Blocking, : TPEG• Textual Advice

– Distribution Channel Directives (Actions)• Guidance to delivery systems: for content management

© 2004Kizoom

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Related Additional Work Items• Situation/Event Structured Incident model UK/FR

– Enhance GMS to have preferred structured incident model for describing disruptions to services, model relates to SIRI, Based on TPEG + TransModel

• Real-time Facility Changes Service FR– Allows changes to availability of facilities and equipment of stop,

vehicle and service to be exchanged in real time . This can be used for example to communicate equipment changes affecting impaired access to PT such as lift or escalator changes. Information is of use to real-time journey-planning and alert services. Should consider interchange aspects.

• Control Actions Server Interface SE – Service for distributing control actions amongst participants, for example

for coordinating management of late services. •

© 2004Kizoom

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XTIS – An “Existence proof”

• Incident Situation Schema – Encoded using SIRI elements & terms– TPEG categories – In use with SIRI GMS in TfL. (Kizoom/MDV)

• Open Points– Road– Relationship to Control Actions– Relationship to Facility/Equipment – Textual Descriptions (where different from derived)

• Categorisation TPEG

© 2004Kizoom

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SIRI - Separation of concerns

DataContent

ExchangeBehaviour

TransportProtocol

well-defined interactionswith XML schemaRepresentations parameterising behaviour

Independent e.g.HTTP POST,SOAP.

definedXML SchemaFor payload

© 2004Kizoom

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TIH

DataContent

ExchangeBehaviour

TransportProtocol

definethroughregistry

simple GETrequest/response(+ allows morecomplex if required,but does not define)

HTTP GET(or CORBA)