2000 09 dh,mm,mts,mz m (xml world 2000) wf-xml tutorial

XML-based standards
for B2B Process Integration

David Hollingsworth, ICL
Mike Marin, FileNET Corp.
Marc-Thomas Schmidt, IBM UK Ltd.
Michael zur Muehlen, University of Muenster

WfMC, September 2000, Slide 1

Overview

 Process Automation and the WfMC
 Standards
 Wf-XML
 Applications


Process Automation and the WfMC

David Hollingsworth


Agenda

 Workflow, Process Automation and business
integration considerations
 Background on the Workflow Management
Coalition
 Process Interoperability Models
 WfMC Standards & ongoing work


What is Workflow

The automation of a business process, in whole
or part, during which documents, information or
tasks are passed from one participant* to
another for action, according to a set of
procedural rules.

*participant = resource (human or machine)


Process Automation
Overview
Process Business Process Analysis,
Designer Modelling & Definition Tools
Process Design
& Definition
Process
Definition
Process Execution
Process
changes
Administrator
/ Supervisor Workflow Management System

Distributed Infrastructure Environment

Work Application
Presentation Launch

Users Applications
& IT Tools

The Process Definition
1. Activity Network - Nodes & Transitions
A2

A1
A6
A3 A5 A8 A10 A11

A7

A4 A9

• Options for Sequential, Parallel & Conditional paths

2. Activity Definitions
• Resource Requirement
• Work Items
• Applications

3. Data Definitions
• Workflow Relevant Data
• (Application Specific Data)

Production & Ad-hoc Workflow

A loose distinction is sometimes drawn between
 Production Workflow
– in which most of the procedural rules are defined in
advance

and

 Ad-hoc workflow
– in which the procedural rules may be modified or created
during the operation of the process.


Autonomous & Embedded
Workflow Products
 Autonomous
– Freestanding independent software package providing workflow
functionality
– Integration with different application systems (desktop or server)
which handle processing of the elementary workflow activities

 Embedded
– Workflow-functionality is part of the (application) software system
(ERP, DM, PPC etc.)
– Controls the sequence of elementary functions of the system
within the application

Differentiation: workflow-enabled versus workflow-based


Business Integration
Requirements

Process

Business Support
Systems Roles &
Responsibilities

Information Organisation

Access &
Ownership
Permissions

Wider Integration Issues

Process
Model

E-commerce Security
& Audit
Information Organisation
Model Model

Legacy Systems

Common Directory Distributed Systems
desktop Services Infrastructure
access WfMC, September 2000, Slide 11

Workflow - Past & Future

 First generation - disjoint applications, human
interface
– Call Centre management
– Correspondence handling
– Claims authorisation, etc

 Second generation - infrastructure, broker /
agent interfaces:
– E-process support (B2Anything)
– Enterprise Application Integration


WfMC Background
 Founded in 1993, to develop & promote
workflow integration capability
 Non profit-making, open to all
 Working arrangements with AIIM, OMG and IETF
 Current membership is c. 220, made up of:
User S. America
Japan / Asia
Analyst / Consultant
US / Canada
Academic &
Research Europe

Vendor
Integrator/VAR


The Workflow Reference Model

Process
Definition Tools

Interface 1 Process Definition Import/Export

Interface 5 Other Workflow
Workflow Enactment Service
Enactment Service(s)
Administration
& Monitoring
Tools Workflow
Workflow
Engine(s)
Engine(s)

Interface 2 Interface 3 Interface 4
- Interoperability
Client Worklist Tool Agent
Apps Handler
Invoked Legacy,
Applications Desktop, etc


Process Definition Interchange

 Purpose
– Exchange of info between BPR tools, workflow systems, process
definition repositories

 Process Definition Meta-Model
– Defines objects, attributes & relationships
– Core Set plus extensible attributes

 WPDL / XML
– Syntax for encoding the process definition

 Process Definition Manipulation APIs
– APIs for reading & writing object & attribute data


Client Application Interface

 Purpose
– To allow applications portability & re-use

 APIs to support
– Process & Activity Control
– Worklist Handling
– Supervisory Process & Activity Control
– Process Definition manipulation

 Language Support
– “C”, IDL & OLE (V2),

 WAPI Specification
– V1 - Published Nov 95, now at V1.4
– V2 - 1998 (joint OMG / WfMC spec)


Applications Invocation
 Purpose
– To provide a common framework for 3rd parties to integrate other
industry application APIs & services
– To support an interface to access legacy applications

 APIs for use by Workflow Engine or Worklist Handler
– Connect/Disconnect
– Invoke Application, Request Status, Terminate

 Status
– Included in WAPI V2


Applications Interoperability

 Purpose
– To allow a business process to be implemented over two or more
workflow systems

 Interchange protocol
– Abstract (functional) specification in IDL for nested & chained
subprocesses
– Binding specification for Internet Mail using MIME
– CORBA version included in OMG submission

 Status
– Full Specification released Q1 97, now with abstract spec, MIME
binding and Wf-XML versions all at current level.
– IDL & CORBA version provided in OMG proposal
– XML version released Q1 2000


Administration & Monitoring

 Purpose
– To allow consistent administration across diverse systems

 Audit specifications
– Audit event identification, formats & recording
– Formal released as full specification Q1 97

 WAPI - Administrative APIs
– Group operations on Processes & Activities Instances
– Status retrieval - Process & Activity instances
– Operations on Process Definitions

 Administration - wider aspects
– - Draft spec of admin functions (audit retrieval APIs and
monitoring policy controls)


Process Interoperability

 Scope may be:
– Local / Departmental
– Enterprise
– Inter-Enterprise

 Style may be:
– Sub-process - hierarchic or chained
– Parallel synchronised

 Purpose:
– EAI
– Web integration, B2B, B2C, etc
– Trading Frameworks / Hub


Distributing the Business Process
Definition Execution

Sub-Process C ? Organisation C

C Organisation A
Process A
B

export

Sub-Process B Organisation B


1. Sub-Process Interoperability Model

A2
A1 A5

A3 A4
B2
B1

B3
B4
C1 C2 C3 C4

WAPI Initiate
Sub-process
Workflow Enactment Service WAPI
#1 WAPI
Return Workflow Enactment Service
#2
Workflow Enactment Service
#3


2. Parallel Synchronised
Interoperability Model

Synchpoint across processes
A1 A2 A3 A4

B1 B2 B3 B4

C1 C2 C3 C4

• To support inter-process dependencies
• Uses Synch Event and optional Confirm

WAPI WAPI
Sync. Event
Workflow Enactment Service Workflow Enactment Service
#1 #2
optional
Confirm


Process Naming & Context

 Activities may be atomic, sub-process call, or in-line
block
 A sub-process inherits characteristics from its process
definition and has its own name space apart from “Root
Process Id” (from initiating process)
 A sub-process call may be specified as synchronous or
asynchronous, binding prefixed or late
 An in-line block operates within the name space and
characteristics of its local process
 Activity and Transition Ids are unique within a process
definition
 Resource naming may use an Organisational Model -
typically unique to a workflow enactment service


The Supply Chain Process Model
Manufacturer Distributor

Place Receive Order Place
Order MRP Order Order DRP

2
QA Confirm Order Schedule Update Update
Order Acknowledgment Receipt Inventory DRP

Schedule Ship Order Advance Receive Ship Order
Shipment Shipment Notice Goods
5

Transport 4 Transport Advance 1 Replenishment
Request Confirmation Shipment Notice

Transportation Company
Request Confirm Receive Update Replenish
Vehicle Transport Goods Inventory Inventory Inventory

Determine Dispatch Release Prepare
International Truck Payment Payment
Order

Advance
Shipment Notice
Transportation Retailer A/P
Prepare Cross
Border
Documentation Company
International Documentation

3

Receive Update Ship Order
Order Inventory

Inventory Third Party
Warehouse Company

Specifications - Context Diagram
Process Definition
Resource Model Tool / Task Process Definition
Interface Interface
creates /
modifies
may
Organisational Model Process Definition
refer to
inherits
is instantiated by properties Audit Specifications
may
refer to

External create, Workflow create & maintain Process Instance
destroy
destroy
Process Instance audit
S/W object modify Manager History
trail
may use
Process & Activity may invoke provides
generates Workflow invocation
Control / Interoperability context
Interface Relevant Data
Workflow Enactment
Work Item
Service

Worklist
Handler I/F may Tool Agent
set
processed by
Application
Worklist Invocation I/F
Application
Handler may
presented invoke 1. Workflow Manager may be distributed, but is
for action by assumed to maintain consistent internal state

Participant 2. Scope of a Process Definition is the enactment service

WfMC - Specifications

 Reference Model (1995)
 Glossary (1994, 1996, 1999)
 Workflow APIs
– “C” (1995)
– IDL / CORBA (1998)
 Interoperability Protocol & Bindings
– MIME (Email) (1995)
– IDL / CORBA (1998)
– Wf-XML (April 2000)
 Audit specification (1997, 1999)
 Process Definition Import/Export Specification
– WPDL (1999)
– UML/XML (planned Q4 2000)
 OMG Submission (Object Model & IDL, 1998)
– Ratified 1999


Ongoing Work Areas

 Security
 Events & parallel synchronised interoperability
standards
 Multiple concurrency workflows (EDI batches)
 XML integration (process definition,
frameworks, data models, etc)


Contacts & Further Information

http://www.wfmc.org
email: wfmc@wfmc.org

david.hollingsworth@icl.com


Process Integration
XML Standardization Initiatives

Mike Marin
FileNet


Introduction

 XML is the universal language of B2B
 Today ad-hoc implementations of B2B abound
– Based on data interchange
– High development cost
 Business start looking into standards
– Decrease cost
– Decrease risk
– Increase potential partners


XML Standards

 Explosion of XML standards
– XML is becoming the language of standardization

 Overlapping functionality
– Some industry segments have competing XML standards

 Emergence of for-profit standardization organizations

 It will take time for the dust to settle


Classifying B2B Standards

 Transport level
 Vertical market vocabularies
 Specific functionality area
 Framework based
 Process based


Transport level

 Moving XML content around
 Examples
– XML-RPC
• Request/Response
– Simple Object Access Protocol (SOAP)
• Unidirectional messages
– Web Distributed Data Exchange (WDDX)
• Exchanging structured data in a generic, cross-platform way


Vertical market vocabularies

 XML standardization for specific industries
 XML Repositories
– XML.org
– BizTalk.org
 Examples
– Chemical Markup Language (CML)
– Text Encoding Initiative (TEI)
– Mathematical Markup Language (MathML)


Specific functionality area

 XML standardization of specific business functions
 Examples
– eBIS-XML
• Order and invoice interchange
– iCalendar
• Calendaring and scheduling
– Directory services markup language (DSML)
• Based on LDAP


Framework based

 Formalized exchange of XML content
 Examples
– BizTalk
– RosettaNet
– ICE
– ebXML


BizTalk

 Horizontally oriented
– Works with vertical market vocabularies that adhere to the
BizTalk conventions
 BizTalk framework is based on SOAP


RosettaNet

 Vertically oriented
– Information technology (IT) supply chain standardization
– Electronic components (EC) supply chain standardization
 Some process
– Predefined partner interface process (PIP)


ICE

– Work with vertical market vocabularies
 Syndicator/Subscriber model
– Request/Response model
 No process concept


ebXML

– Based on a repository
 Goal is to create a single global electronic
market
 Compatible with EDI
 Some process concepts


Process based

 Business process oriented
– General workflow functionality is horizontal
 Example
– Wf-XML


Summary

 A crowded field
 Research your vertical market first
 Talk with the partners you intent to engage


Wf-XML Interoperability Standard

Marc-Thomas Schmidt
IBM UK, Business Integration Architecture
mts@uk.ibm.com


Wf-XML Scenario

 Enable interaction between Requesters and Providers of
‘workflow-type’ Business Services
– Standardise minimum set of operations for managing interactions
with potentially long running services

 Service Requester
– Requests service to be performed
– Inquires about status of execution

 Service Provider
– Processes service requests
– Informs requester on status of the request

 One Party can play both roles

Wf-XML Scenario Illustrated
Requester Provider Requester
Provider
Do It

Done It
Query &
Control

Party A Party B Party C


Multi-Party Interactions

Party A Party B

Party C


Interaction Partner Checklist
Services Repository
 Provider advertises service
– Service interface definition, including in/out data, potential
transports, Quality of Service, service constraints, ...
 Requester selects service matching their needs
Trading Partner Agreement
– Required business function, requested Quality of Service, ...

 Provider & Requester agree on interaction contract
– Transport, Security, Quality of Service, Data Representation,
Wf-XML
…
 Requester and Provider perform interaction
– Requester initialises and starts service
– Provider accepts request and initiates service
– Requester may query status or cancel service request
– Provider completes request and returns results

Trading Partner Agreements
Examples
Overall properties // Contract duration
Identification // Business partner info.
Communication properties // HTTP, SMTP, etc.
Security properties
// Authentication, non-repudiation
Roles // Buyer, seller, broker, etc.
Actions // Reserve, modify, etc.
Responsiveness // Timeout
Sequencing rules // Modify after reserve
Constraints // Modify before 6 p.m
Recourse actions // Refund, etc.
Error handling // Retries, actions invoked
Legal text // Penalty if unreachable


Wf-XML Specification
 XML Message Set for Interactions between requesters and
providers of Workflow Business Services
 Based on existing Workflow Interoperability Standards
initiatives
– WfMC Workflow Interoperability Specification, OMG Workflow
Management Facility (a.k.a jointFlow), Simple Workflow Access
Protocol (SWAP)
 Main Features
– A structured and well-formed XML message set encoding
– Synchronous or asynchronous message-handling capability
– Independence from transport mechanism
– Easy extensibility through the use of XML and dynamic workflow
context data


Wf-XML Resource Model
Observer
 Resources Create
– … are identified by URI-type keys Instance
– … provide a set of operations
 Process Definition Provide
Feedback
– Factory for service providers
 Process Instance
– Realises a workflow business service Control &
– Parametrised by workflow context Query
Context
data data
 Observer
– Represents service requester
Process
Definition
Process
Instance


Workflow Context Data

 Define the workflow relevant instance variables of a
workflow process business service
– Initialised during instantiation of the process
– Provide context for tasks in a workflow process
– Updated by workflow tasks

 Example
– Process Product Order takes Order Request as input
– Stepwise completion of the Order Request during process
execution, documenting progress of the workflow process
– Order Completion notice upon process termination


Process Definition Resource

 Resource used to instantiate a particular workflow
business service
– Represents particular workflow process template
– May be located via Service Repository
– Internals of workflow process realisation not exposed

 CreateProcessInstance Operation
– Takes workflow context data for process instance as input
– Optionally allws for registration of process instance observer
– Returns Process Instance identifier for future reference

 Example
– Process Product Order Process
– Takes specific Order details as input


Process Instance

 Resource representing a particular instance of a workflow
business process
– Execution state - basic, extensible state model
– Workflow context data - input data plus intermediary results
– Informs its observer about state or context data changes
 GetProcessInstanceData operation
– Retrieves current content of workflow context data set
– Can be used to retrieve final or intermediary results of process
 ChangeProcessInstanceState operation
– Changes the execution state of the process instance
– Can be used to suspend or terminate process instance
 Example
– Process Product Order of 42 pencils for Marc-Thomas Schmidt


Process Instance State Model

 Defines basic set of execution states
– Nested states
– Level 1 and 2 mandatory, level 3 optional

 Can be extended by workflow service specialisations

closed
open
abnormalCompleted
notRunning
aborted
suspended
terminated

running
completed


Observer

 Resource representing a service requester
– Registered with process instance during creation
– Receives notifications on change of execution state and changes
in workflow context data of a process instance
– Up to service provider to determine which status changes are
propagated
– Future extensions may extend role to represent any party
interested in process instance

 ProcessInstanceStateChanged operation
– Takes current execution status and workflow context data as
input

 Example
– Initiator of a workflow process; may be another process


Wf-XML Message Set

 Messages represent operations on Wf-XML resources
– Message pairs representing request-response model
 XML encoding of message content
 Transport Header
– For future use
 Message Header
– Indicates message type (request or response) and identifies
resource which is target of request or source of response
 Message Body
– Identifies operation, provides operation-specific parameters and
eventual error codes
– Pattern: OperationName.Request or OperationName.Response


Workflow Context Data Encoding
 Context Data encoding outside of Wf-XML scope
– Message definitions use placeholders for context data
– ContextData tag in request, ResultData tag in response messages
with content model ANY

 Examples
– Name-value pairs
<name>item01</name><value>foo</value>
– Structured, tagged data
<vehicle>
<vType>Car</vType>
<vMake>BMW</vMake>
</vehicle>
– XML Schema encoding
<xs:complexType name="length2">
<xs:element name="size" type="dt:non-positive-integer"/>
<xs:element name="unit" type="dt:NMTOKEN"/>
</xs:complexType>


CreateProcessInstance.Request
<?xml version=“1.0”?>
<WfMessage Version=“1.0”> Identifies process
<WfTransport/> definition
<WfMessageHeader>
<Request ResponseRequired =”Yes”/>
<Key>http://www.compInc.com/WfSrv?id=1199827</Key>
</WfMessageHeader> Request to create
<WfMessageBody> process instance
<CreateProcessInstance.Request StartImmediately =”true”>
<ObserverKey>http://www.Acme.com/wfx456</ObserverKey>
<ContextData>
<Computer>
<Type>thinkpad</Type> Observer to be
Context data for
<Series>600X</Series> notified of process
this process
<Option>DVD</Option> updates
instance
</Computer>
</ContextData>
</CreateProcessInstance.Request>
</WfMessageBody>
</WfMessage>


CreateProcessInstance.Response -
Success
<WfMessage Version=“1.0”> Identifies process
<WfTransport/> definition that
<WfMessageHeader> performed request
<Response/>
<Key>http://www.computerInc.com/WfSrv?id=1199827</Key>
</WfMessageHeader>
<WfMessageBody>
<CreateProcessInstance.Response>
<ProcessInstanceKey>http://www.compInc.com/pi42</ProcessInstanceKey>
</CreateProcessInstance.Response>
</WfMessageBody>
</WfMessage>

Identifier of newly
created process
instance


CreateProcessInstance.Response -
Errors
<WfMessage Version=“1.0”>
<WfTransport/>
<WfMessageHeader>
<Response/>
<Key>http://www.comInccom/WfSrv?id=1199827</Key>
</WfMessageHeader>
<WfMessageBody>
<CreateProcessInstance.Response>
<Exception>
<MainCode>502</MainCode>
<Type>F</Type>
<Subject>Invalid Process Definition</Subject>
Exception <Description>Can not create instance</Description>
information </Exception>
</CreateProcessInstance.Response>
</WfMessageBody>
</WfMessage>


GetProcessInstanceData.Request
<WfTransport/> Process Instance ID
<WfMessageHeader> (from previous
create request)
<Key>http://www.compInc.com/pi42</Key>
</WfMessageHeader>
<WfMessageBody> Identifies context
<GetProcessInstanceData.Request> data we want to
know about
<ResultDataAttributes>
<Priority/>
</ResultDataAttributes>
</GetProcessInstanceData.Request>
</WfMessageBody>
</WfMessage>


GetProcessInstanceData.Response
<WfTransport/> Process Instance ID
<WfMessageHeader> we send the request
to
<Response/>
<Key>http://www.compInc.com/pi42</Key>
</WfMessageHeader>
<WfMessageBody> Returns only the
<GetProcessInstanceData.Response> properties we asked
for
<ResultDataAttributes>
<Priority>5</Priority>
</ResultDataAttributes>
</GetProcessInstanceData.Response>
</WfMessageBody>
</WfMessage>


ChangeProcessInstanceState.Request

<?xml version=“1.0”?> Process Instance ID
<WfMessage Version=“1.0”> (from previous
<WfTransport/> create request)
<WfMessageHeader>
<Key>http://www.compInc.com/pi42</Key> This is the state we
</WfMessageHeader> want the process
<WfMessageBody> instance to take on
<ChangeProcessInstanceState.Request>
<State>closed.abnormalCompleted.terminated</State>
</ChangeProcessInstanceState.Request>
</WfMessageBody>
</WfMessage>


ProcessInstanceStateChanged
Message
Observer ID
<WfMessage Version=“1.0”> (registered with
<WfTransport/> process instance
<WfMessageHeader> during create)
<Request ResponseRequired =”No”/>
<Key>http://www.Acme.com/wfx456</Key> Process Instance
</WfMessageHeader> that sends the
<WfMessageBody> notification
<ProcessInstanceStateChanged.Request>
<ProcessInstanceKey>http://www.compInc.com/pi42</ProcessInstanceKey>
<State>closed.abnormalCompleted.terminated</State>
<ResultData>
<Order>ACM00456</Order>
<Account>ACM-400-2460</Account> State of the
<Amount>150.00</Amount> process instance
Context data of
</ResultData> process instance
<LastModified>1999-12-25T15:10:35Z</LastModified>
</ProcessInstanceStateChanged.Request>
</WfMessageBody>
</WfMessage>


Transport Bindings

 Wf-XML does not mandate binding to a particular
transport protocol
– Potential transport protocols include HTTP, SMTP, MOM
 HTTP binding
– Operations map to HTTP POST
– Resource key is the URI to which a Post method is directed
– The Wf-XML request is the request message body for input
– The Wf-XML response is the response message body for output
– Both request and response specify “Content-type: text/xml” in the
HTTP message header.
– Authentication is accomplished through the standard HTTP
mechanisms


Summary

Michael zur Muehlen
University of Muenster
Department of Information Systems
ismizu@wi.uni-muenster.de


Use of Wf-XML

 (Currently) Peer-to-Peer Communication
 Encapsulation of local process logic
– Observe ACID Principles of Database Management
– Syntactic abort of remote process may not equal a
semantic abort
– Change of local process logic may lead to global
deadlocks: Observe partial serialization of process
interfaces
 Wf-XML is very suitable for Service Outsourcing
approaches
– Academic research: WISE, CrossFlow
– Commercial projects


Wf-XML in the Business Scenario

 Prerequisites
– HTTP is initial transport binding, but Wf-XML is not limited
to this
– Workflow Management System is not necessarily required
• Wf-XML Adapters for ERP systems
• Wf-XML Adapters for Web Application Servers
• Wf-XML Adapters for EJB Services
– Few operations, well defined API – (relatively) little
implementation effort
– Wf-XML workflow-enables existing business infrastructure


Wf-XML Status and Outlook

 First version of the standard published by
WfMC May 2000
– Basic set of Interoperablity messages
– HTTP binding available
 Future work areas
– Additional bindings
– Generalisation of Observer role
– Process Definition introspection and link to Service
Repositories
– Process Instance update operations and execution
monitoring
– Link to Trading Partner Agreements and similar interaction
contract definitions


Process Instance Update
Operations and Execution Monitoring
 Re-send (additional) context data during remote
process execution
 Monitoring of fine-grain process structure
– Currently only coarse granularity of state changes
– Filtering and/or translation of monitoring data
– Integration of monitoring data from different sources
(cascaded monitoring)
– WfMC Interface 5 as a starting point for monitoring data
specification


Execution Monitoring

 Currently: “push“ of coarse state change
information to observer

Process
Observer
Instance

 Future: Integration of fine grain monitoring data
over several involved parties

Process Process
Observer
Instance Instance


Example: Web-based Helpdesk


Observer for User Monitoring Data


Details of Cascaded Processes


Re-Querying of Process Context Data


Workflow Standards Timeline

Keith SWAP
Swenson IETF Standardization
et al. Initiative
WfMC
Reference WfMC (1998) SWAP
Model IF 4 V 1.0 Working Wf-XML
V 1.0
Group
WfMC
founded
WfMC
(1993) jointFlow IF 4 V 2.0
Working Group Interoperability
Challenge
OMG Resource Ass. Int. RFP
founded Process Modeling RFP
(1989) OMG OMG OMG
Object CORBA 2.0 Workflow
Management Specification Facility (8/98)
Architecture
1993
1989

1995

1999

2000

Wf-XML

 Adds the process dimension
 Has evolved from a solid foundation
– WfMC
– OMG
 Does not overlap with other XML standards
 Is complementary to most XML standards
 Has industry support


Wf-XML Future

 Establish a dialog with other XML standards
– Context data providers
– Process providers/users
 Show how it complements other XML standards
– Integration of vertical data sets as context data
– Analysis of requirements of standards with process
components (e. g. RosettaNet PIPs)


2000 09 dh,mm,mts,mz m (xml world 2000) wf-xml tutorial

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