WOS@UniZH 17.08.991 The Web Operating System Towards Wide Area Ubiquitous Computing Joint work of P. Kropf, G. Babin, (University of Laval, Canada) J

WOS@UniZH 17.08.99 1

The Web Operating System Towards Wide Area Ubiquitous

Computing

Joint work of

P. Kropf, G. Babin, (University of Laval, Canada)J. Plaice (University of Sydney, Australia)

H. Unger (University of Rostock, Germany)A. Mikler (University of North Texas, USA)

S. Schubiger (University of Fribourg, Switzerland)O. Krone (Swisscom CT, Switzerland)


Overview

• Motivation

• The WOS Approach– Resources

– Warehouses

– Eductive Engine

– WOSNode, WOSpace

• Web Components (WebComs)

• Current Research Issues

• Related, and Future Work, Conclusion


Motivation

• Success of the WWW is tremendous

• Why not using WWW as platform for ubiquitous computing ?

• Today: resources found on the Web are information only; interaction is limited

• Tomorrow: use WEB as a Service Space: “The network is the computer”


Motivation (cont.)

Service Provider: e-mail stock quotes GSM gateway supercomputer

Supercomputer

Residential userusing e-mail at home

Legend:

connecting services

using services

WOS compliant e-mailservice

User travelingReceiving stock quotes ande-mail via GSM

At workusing supercomputer cycles

Stock quotes

WOS Service SpaceGSM Service


Motivation (cont.)

• Network Applications– WWW, email, video

• Computational Applications– number crunching, distributed simulation

• Virtual Entities– classrooms, companies

• Knowledge based Applications– data mining, databases

• Real Time Applications– process control real-time multimedia


The WOS Approach

• 5 Universities involved: Laval, Rostock, Texas, Sydney, Fribourg

• “Operating System” for the Web

• Runs on top of existing OS, Java

• Bringing the resource-richness of the Web to the user

• Bringing the computational potential of the Web to the user

• Distributed and versioned


Web Operating System - Warehouses

• Resource database• Resource management• Resource cache• Passive Warehouses

– storage for service information– information out of date, must be replaced

• Active Warehouses– information obtained from which other warehouse

• Adaptive Warehouses– user profiles and access statistics: update of information


Web Operating System - Resources

• Versioned Services• Applications• Platforms• Hardware• …


Web Operating System - Eductive Engines

?

• Provides services using a warehouse • Reactive system• Responds to requests• Eduction (Oxford English Dictionary):

“The action of drawing forth, eliciting, or developing from a state of latent, rudimentary, or potential existence; the action of educing (principles, results or calculations) from the data.”

WOS@UniZH 17.08.99 10

Web Operating System - WOS Node

?

Eductive engine + Warehouse

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Web Operating System - WOSNet

?

?

?

?

?

?

?

?

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Network of WOS Nodes

• Eductive engine• Warehouse

?

?

?

WOS@UniZH 17.08.99 12

Web Operating System - Operation

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WebComponents (WebComs)

• Resource Representation Interaction [Schubiger, Krone] – Based on data flow networks

hello.c

hello.exe

?

semantic

semantic

=

file

name

path

content

c-source

file

name

path

content

os

architecture

hello.c

hello.exe

?

WOS@UniZH 17.08.99 17

WebComs (cont.)

• Attribute schemes– capture real world representations (concepts) e.g. files,

programs, source-code,…

– are constructed

–by description

– set operations (union, intersection,…)

– an attribute scheme is either

– implicit

–native

– relation based on other attributes

file

name

path

content

c-source

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WebComs (cont.)• Passive WebComs

– representations for non-executable resources

– passive WebComs have an attribute scheme

• Active WebComs– representations for executable resources

– active WebComs are passive WebComs with an action

– an action has two sets of plugs

– input plugs

–output plugs

– each plug has an associated attribute scheme

file

name

path

content

c-source

semantic hello.c

compiledebug

=

content

semantic

c-sourcecontent

semantic

o-file

optimized

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WebComs (cont.)

hello.c

hello.exe

?

semantic

semantic

=file

name

path

content

c-source

compiledebug

semanticsemantic

optimized

=

file

name

path

content

c-source

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WebComs (cont.)

hello.c

hello.exe

compile

link

debug

=

=

semanticsemantic

semantic

semanticsemantic

semantic

optimized

name

=

true

false

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WebComs (cont.)

compiledebug

=

content

semantic

c-sourcecontent

semantic

o-file

optimizedhello.c

file

name

path

content

c-source

semantic

link

=content

semantic

o-file

content

semantic

executable

compiledebug

=

content

semantic

c-sourcecontent

semantic

o-file

optimized

=

Attribute scheme of a plug has to be equal to attribute scheme of the other plug

The attribute scheme of the plug has to be a subset of the attribute scheme of the passive WebCom

WOS@UniZH 17.08.99 22

WebComs (cont.)

ServicesResources

WebComs

Warehouses

hello.c gcc hello.o ld hello

hello.c compile link hello= =

• Example: Unified Messaging– input WebCom: message

– output WebCom: desired format of the message

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Current Research Issues

• WOS Node Architecture [Unger]

– node is client

– and server

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Current Research Issues (cont.)

• Communication Protocols [Babin, Kropf, Unger]

– Two level communication protocol

discovery/location protocol (WOSRP) location of specific WOS nodes

generic Service Protocol (WOSP)

* versioned protocol; bind node to appropriate instance of WOSP analyzer

* setup, execution, querycommands

t1

t2

Node

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• Service Search [Unger, Kropf, Babin, Boehme]

– information about local and remote services stored in WOS node

– broadcast or serial chain mechanism, search trees

– combination of both theoretical research performed: 6-10 chainsin parallel result in goodresponse time

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Research Issues (cont.)

• Fault Tolerance [Babin, Kropf, Unger]

– WOS server cannot serve the request after receiving it

– Network brake downs

– WOS nodes/machines crash

Acknowledge protocol developedreceive acknowledgment(RACK)termination acknowledgment(TACK)

node i-1

node i

node n-1

node n

MSGMSG

MSGMSG

RACK

RACK

RACK

TACK

TACK

TACK

RACK

t

t

t

((n-i-2)+(n-i-2)

2/n)*t

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• Load Management [Unger, Kropf, Plaice]

– global online resource prediction impossible

– transmission time: data might be outdated upon arrival

– reaction in case of failure of nodes

– off line learning and adaptation techniques cannot be used

user manager: statistical data of processes started by a specific user

machine manager: arranging allocation of local resources

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• Resource Representation & Interaction [Krone, Schubiger]

– how can resources be manipulated and shareduse desktop metaphor for explicitmanipulation: WebRes* based on RMI;* introduced novel technique (dynamic linking) for runtime linking of objects

implicit through (WebComs) data-flow driven

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WebRes

* resource set* user interface* resource servers

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• Coordination Issues (use Linda as inspiration)Manifold, STL, ...

• Negotiation Techniquesfor e-commerce

• Mobile Agent Technology

• Graphical User Interface

• Security Issues (!)

• Cost Model for Resources

Linda’s Tuple SpaceLinda’s Tuple Space

in()

out()

rd()

eval()

[x,12, y]

[“Hallo”,12, y]

WOS@UniZH 17.08.99 31

Related Work

• Inferno (Lucent Technologies)

• IBM’s T-Spaces

• Berkeley’s WebOS (part of NOW)

• SuperWeb and Charlotte

• Microsoft’s Millennium project

• and of course SUN’s Jini

• …

WOS@UniZH 17.08.99 32

Related Work (cont.)

Service Provider

Service ObjectService Attributes

Lookup Service

Service ObjectService Attributes

Client

Service Object

(1) registration(2) lookup

(3) use

WOS@UniZH 17.08.99 33

Related Work (cont.)• Jini

– services as resource encapsulation

– lookup service as resource directory

– leasing for access control

– events for notification

– based on JavaSpaces (Linda variant)

• WOS– warehouses with versioned services

– WOS’ “federations” are dynamically and autonomously created

– language independent (protocol)

WOS@UniZH 17.08.99 34

Future Work

• Extend WebRes to be used with WebComs– Definition of the network language

– Graphical network builder

– Interactive/automated resource selection (Agents/Web robots)

• Develop adapters for legacy software (CORBA)

• Validate Service Search Techniques

• Further investigate CORBA and Jini and her friends

• Look at Security Aspects

• Consolidation of already developed prototypes

WOS@UniZH 17.08.99 35

Conclusion

• Presented the WOS effort, ongoing research project, 5 Universities

• Goals– develop methods, frameworks for future interconnected

systems

– contribute to future global information infrastructure

• Both industry and academia is interested

• Version 1.0 is on its way

• Conference: Web Communities, June 2000, University of Laval

• Info: http://paradis.ift.ulaval.ca/projects/wos

Documents

WOS@UniZH 17.08.991 The Web Operating System Towards Wide Area Ubiquitous Computing Joint work of P. Kropf, G. Babin, (University of Laval, Canada) J