ECOO: Environment and COOperation

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ECOO Environment and COOperation

• Hala Skaf-Molli
• Assistant Professor University Nancy1
• LORIA-INRIA lorraine
• skaf_at_loria.fr

• Pascal Molli
• Assistant Professor University Nancy1
• LORIA-INRIA lorraine
• molli_at_loria.fr

www.loria.fr
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ECOO Members
Responsable Claude Godart, Prof. UHP, ESSTIN
Phd students(8) Karim Baina, Julia Bitcheva
Christophe Bouthier Abdelmajid
Bouazza Daniela Grigori Benoît Sonntag
Samir Tata Olivier Zendra
Ingenieur(3) Philippe Canalda Saâd El
Hadri Marc Patten
Permanents (10) Khalid Benali, MC Nancy
2 Nacer Boudjlida, Prof UHP Gérôme Canals, MC
Nancy 2 François Charoy, MC Nancy 2, CR INRIA
(sept 00 -- sept 02) Dominique Colnet, MC UHP, CR
INRIA (sept 99 -- sept 01) Luigi Liquori, MC
INPL, Jacques Lonchamp, Prof. Nancy 2 Pascal
Molli, MC UHP, CR INRIA (sept 00 -- sept
02) Olivier Perrin, MC Nancy 2 Hala Skaf-Molli ,
MC UHP
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Applications

• Cooperative work
• Co-conception, co-authoring, co-engineering,
  virtual teams, virtual enterprises
• Keywords
• CSCW, Workflow, Software Engineering, Distributed
  systems, Databases Systems

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Industrial Relations...

• AEE (Renault, Valéo,..)
• Interoperability of processes
• CNET (France-Télécom)
• Virtual teams for architects
• Hitachi Japan
• Flexible workflow
• ...

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Virtual Teams

• Team
• A group of people interact through interdependent
  tasks guided by a common goal
• Virtual
• Distributed across the time, space and the
  organizations
• Linked by webs of communications technologies

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Introduction

• Why virtual teams ?
• Quickly gathered core competencies of different
  organizations
• Work is achieved in a competitive time
• High-productivity, Mobility
• Examples
• Research project (AAE, CNET, Hitachi )
• Co-authoring (web), co-design

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Introduction

• Providers host virtual teams
• BSCW Reference of CSCW community for shared
  workspace, a commercial product now
• SourceForge 10000 open source projects, 70 000
  virtual members
• HotOffice, TeamCenter, Egroups, Instant!TEAMROOM
  Commercial products

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Virtual team services

• Shared data
• Object and dependencies, Concurrency, versioning,
  annotation, Access Control, Notification
• Communication Services
• Synchronous video-conference, application
  sharing, collaborative tools, shared whiteboard,
  chat
• Asynchronous Mailing list, web pages, forums,
  persistent notification

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Virtual Team Services

• Coordination Tasks management
• Manual Project Management
• Enacted ToDo List
• Defined in a process and enacted Workflows
• Awareness pertinent
• Activity awareness, Availability awareness,
  Process awareness.

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Problems

• Shared data consistency
• Concurrent access to shared data
• Coordination
• Implicit coordination (informal)
• Explicit coordination (formal)

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Shared Data in Virtual Teams
Private Workspace
Private Workspace
Private Workspace
Shared Workspace
Private Workspace
Private Workspace
Private Workspace
Private Workspace
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Shared Data and Copy-Modify-Merge
Private Workspace
Private Workspace
Private Workspace
Shared Workspace
Private Workspace
Private Workspace
Private Workspace
Private Workspace
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Shared Data and Consistency
a
b
C
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Data Consistency

• Transactional approach
• Encapsulate activities in transactions.
• The system will take in charge the problem of
  concurrent access

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Data Consistency
Private Workspace
Private Workspace
Private Workspace
Shared Workspace
Private Workspace
Private Workspace
Private Workspace
Private Workspace
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Data Consistency

• Results
• Coo-serializability new correction criterion
  for cooperative executions
• Coo-transactions new advanced transaction model
  based on coo-serlializability
• COO prototype a cooperative development
  environment based on the coo-transactions.

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Problems

• Shared data consistency
• Concurrent access to shared data
• Coordination
• Implicit coordination (informal)
• Explicit coordination (formal)

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Informal Coordination

• Gutwin, Roseman and Greenberg in CSCW96
• "Workspace awareness reduces the effort needed
  to coordinate tasks and resources, help people to
  move between individual and shared activities,
  provides a context in which interpret utterance,
  and allows anticipation of others actions

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Informal Coordination

• Coordination based on group awareness
• Keep team members informed about the project
  activity..
• So they will communicate...
• And auto-coordinate.
• Essential problem
• Providing pertinent information.
• Which information ? when ? To whom ?

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Informal Coordination

• A pertinent source of information
• The measurement group divergence.
• Group divergence
• Measure the quantity of disorder between the
  different copies of shared data...

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Divergence
Divergence concurrent modifications on the
different copies of the object. Convergence
integration of parallele modifications ...
Divergence

time

User1

User2

synchro. Points
User3
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Divergence/convergence

• Divergence phase Monitor...
• Convergence phase Accelerate...
• Convergence points COO-SR

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Divergence

• How to measure divergence?
• How to propagate it ? According to which model ?
• How to visualize it in a real time ?

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How to Measure Divergence?

• Configuration management approach
• Copy/modify/merge calculate the difference
  between the different copies of an object
  flexible merge, diff
• Transactional approach
• Number of dirty reads ?-serializability
• Operational transformation
• Number of conflict operations Ellisgibbs,
  SOCT4.

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Divergence Propagation

• Divergence is the quantity of disorder in objects
  network
• It propagates through dependencies between
  objects ...

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Divergence Visualization

• User must be able to monitor divergence
  variation like CPU load or network activity.
• Peripheral, scalable, customizable...

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Divergence Visualization
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Divergence Visualization
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Divergence Visualization
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Experimentation

• Prototype
• MOTU prototype is under realization in an
  advanced step..
• motu.sourceforge.net
• Hypothesis
• If users visualize divergence in a real time so
  they will communicate to auto-coordinate.
• Experience
• Clinical studies on virtual teams disposed on
  information about divergence.
• This is the objective of the project COCAO with
  CNET.

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Conclusion on Informal Coordination

• Divergence is a pertinent source of notification
• A peripheral visualization allows user to
  monitor divergence like CPU load or network
  activity..
• Auto-coordination

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Problems

• Shared data consistency
• Concurrent access to shared data
• Coordination
• Implicit coordination (informal)
• Explicit coordination (formal)

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Formal Coordination

• Approach based on workflow (explicit
  coordination)
• Workflow is used in several domains to coordinate
  works
• Example coordinate tasks in office automation
• Use it to coordinate virtual teams !

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Workflow Management System

• Two components
• Process definition (declarative or/and visual)
• Define tasks ...
• Who must accomplish the task
• Define transitions between tasks.
• Process execution engine
• Execution environment
• Users tasks appear on their desktop...

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Example Loan Request Handling

• Activities
• Collect credit information
• Assess risk (amount lt 10 000 FF)
• Request approval (amount gt 10 000 FF or high
  risk)
• Accept credit
• Reject credit

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Control flow of activities
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My activities
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Workflow

• Actual workflow systems are rigid
• End-gtbegin dependency
• Execute in isolation
• Add flexibility to workflow systems

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Cooperative Workflow

• Two methods
• Change the execution engine
• Keep the model simple (minimal modifications)
• Accept cooperative executions (break isolation)
• Change the process model
• Add cooperative operators to the model

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Change the Execution Engine

• Anticipation..
• If intermediate results are available you can use
  them
• To start tasks as soon as
• Example process of write/ review a document

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Conclusion on Anticipation

• Easy to do, to understand
• No modifications on the process's model
• According to the users needs

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Cooperative Workflow

• Two methods
• Change the execution engine
• Keep the model simple (minimal modification)
• Take in consideration cooperative executions
• Change the process model
• Add cooperative operators to the model

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Change the Process Model

• Cooperation is defined and controlled explicitly
• 3 cooperation patterns
• Client server
• Redactor reviewer
• Cooperative writing
• Users can negotiate their cooperation strategy

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Cooperation Patterns

• Client/Server
• NO concurrent modifications on shared data

• Redactor/reviewer
• Cross reading of shared data

• Cooperative Writing
• Concurrent modifications

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Example Cooperative Write
A
Edit
Shared workspace
B
Edit
Cooperative Operator
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Application

• Project Corvette between Hitachi Japan and the
  ECOO team of Loria
• Cooperative patterns are implemented in Motu..
• Adding cooperative operators to the workflow
  system WorkCoordinator" developed by Hitachi
• Adding flexibility to WorkCoordinator

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Conclusion on Cooperative Workflow

• Cooperation is defined
• Explicitly
• With cooperation patterns
• Choice of cooperation strategy
• Flexible workflow

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General Conclusion

• Data consistency
• Coo-transactions
• Two approaches
• Informal coordination
• Auto-coordination based on group awareness
• Divergence metrics
• Formal coordination
• Cooperative workflow
• Flexible execution

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Cooperation with Universities of Sydney

• Integrating of Network Services for Virtual Teams

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Virtual Teams and Network Services

• Virtual teams services
• Shared Data, Coordination, Communication,
  Awareness
• But...
• Security, Predictive behavior, Quality of
  services are required to make it commercially
  viable...

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Limitations of Existing Virtual Teams Software

• Predictive behavior
• Not sure to access any virtual team service
• Servers downs, service interrupted by provider
• Software not designed to handle scalability

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Limitations of Existing Virtual Team Software

• Security
• Access are (poorly) authenticated, Web access use
  SSL
• Other kinds of connection use SSH

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Limitations of Existing Virtual Team Software

• Quality of service ?
• Video-conferencing relies on video-conferencing
  software
• File sharing through normal FTP
• Awareness notifications not delivered in
  bounded time

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Virtual Team Nature

• High productivity
• members have to start a virtual team as soon as
  possible
• Deployment of security, quality of service have
  to be compatible with this requirements
• Mobility
• Virtual team members are mobile
• Virtual team services HAVE TO be available with
  the same quality of service if people move

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Requirements for network services

• Security, Quality of service, predictive behavior
• Compatible with
• High-productivity and Mobility
• Virtual team business

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Experimentation

• Motu is a prototype for virtual team developed
  by the ECOO team at LORIA
• Shared Data Multi-version file system, long
  transactions, ACL, Notification API
• Coordination Workflow engine
• Awareness Presence awareness, State awareness,
  divergence awareness
• Communication instant message, built-in
  video/audio conference

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motu.sourceforge.net
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Experimentation

• Integrate in the Motu prototype Security, Quality
  of service
• Experiments the result between France and
  Australia
• Motu is 100 java software, communications use
  RMI, and IP-multicast for video-conference

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Conclusion

• Writing a paper about Integrating Network
  Services for Virtual Teams
• ECOO team, LORIA competencies in Virtual
  Teams..
• UNSW, UWS competencies in network
• Evaluate cost and complexity of integration Qos
  and Security on existing VT software
• Do it on the Motu prototype

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I N T E R N E T Q U A L I T Y
Coordination
A W A R E N E S S
Formal Informal Workflow Awareness
Communication
Synchrony Asynchrony Chat, email,
mailing-lists, Videoconference, forum
Shared whiteboards shared agenda
Shared Data
Versions, Replication, Configuration,
Concurrency, Consistency
TOOLS
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I N T E R N E T Q U A L I T Y
Coordination
A W A R E N E S S ??
Formal Informal Workflow Awareness
Communication
Synchrony Asynchrony Chat, email,
mailing-lists, Videoconference, forum
Shared whiteboards shared agenda
Shared Data
Versions, Replication, Configuration,
Concurrency, Consistency
TOOLS
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A W A R E N E S S
Communication
I N T E R N E T
Synchrony Asynchrony Chat email
Videoconference forum
Shared Data
Versions, replication, Configuration,
Concurrency, Consistency
TOOLS