abc - ad-hoc collaboration - 24/03/2006 1 abc ad-hoc collaboration

ABC - Ad-hoc collaboration - 24/03/2006ABC - Ad-hoc collaboration - 24/03/2006 11

ABCABC

Ad-hoc collaborationAd-hoc collaboration


AgendaAgenda

Activity Based Computing (short)Activity Based Computing (short)• What is ABC?What is ABC?

The current hybrid architectureThe current hybrid architecture• Current architectureCurrent architecture• Pros. et. cons.Pros. et. cons.

P2P infrastructure based on DOLCLANP2P infrastructure based on DOLCLAN• Peer-to-peer Distributed Shared ObjectsPeer-to-peer Distributed Shared Objects

Ad-hoc ABC collaborationAd-hoc ABC collaboration• StatusStatus


Activity Based ComputingActivity Based Computing



Activity-basedActivity-based Collection of related servicesCollection of related services Many concurrent activitiesMany concurrent activities

Session migrationSession migration The user’s session is distributed across the hospitalThe user’s session is distributed across the hospital Suspend – Resume Suspend – Resume Heterogeneous devices Heterogeneous devices

CollaborationCollaboration Shared activity (‘tele-conference’) (different places)Shared activity (‘tele-conference’) (different places) Synchronous (same time) + Asynchronous (different time)Synchronous (same time) + Asynchronous (different time) Ad-hoc (Any place, but synchronous)Ad-hoc (Any place, but synchronous)

Context AwarenessContext Awareness The computer adapts itself to the user’s context (PACS)The computer adapts itself to the user’s context (PACS)


The current architectureThe current architecture

Client-ServerClient-Server Easy to createEasy to create PerformancePerformance ScalabilityScalability

Hybrid architectureHybrid architecture AccountableAccountable EphemeralEphemeral


Hybrid architectureHybrid architecture

ProsPros Concurrency controlConcurrency control Late joiningLate joining SecuritySecurity MembershipMembership InvitationsInvitations Synchronous collaborationSynchronous collaboration Asynchronous collaborationAsynchronous collaboration Failure detection / handling / repairingFailure detection / handling / repairing Discovery serviceDiscovery service

ConsCons Disconnected collaborationDisconnected collaboration Ad-hoc collaboration (Anywhere)Ad-hoc collaboration (Anywhere)


ShortcomingsShortcomings

Ad-hoc collaborationAd-hoc collaboration No infrastructureNo infrastructure Collaboration anywhereCollaboration anywhere Disconnected collaborationDisconnected collaboration


P2P infrastructure - DOLCLANP2P infrastructure - DOLCLAN

Distributed Objects in Loose Coupled Distributed Objects in Loose Coupled Local Area NetworksLocal Area Networks


PDSO and groupsPDSO and groups

Peer-to-peer Distributed Shared ObjectsPeer-to-peer Distributed Shared Objects OIDOID PDSOPDSO GroupGroup


Model View ControllerModel View Controller


SyntaxSyntax

public distributed class DistributedPoint {

//A distributed Pointprivate distributed ephemeral int x;private distributed ephemeral int y;...

}


SyntaxSyntaxpublic distributed class DistributedPoint : Observable {

//A distributed x positionprivate int x;public distributed ephemeral int X{

get { return this.x; }set {

this.x = value;//Notify observersthis.stateChanged();

}}

//A distributed y position...

}


SyntaxSyntax

public void start(){OID[] oids = EaterModel.getOIDs();if (oids.Length > 0){

model = join EaterModel(oids[0]);} else {

model = new EaterModel("MyGame",10);}...

}


SyntaxSyntax

public distributed class DistributedStone : Observable {...public void merge(object netState){//Cast the object to a DistributedStoneDistributedStone netStone = (DistributedStone)netState;

//The position never change, so thats up to date

//Figure out if the stone has been eaten either offline or onlinethis.Eaten = (this.Eaten || netStone.Eaten);}

}


An exampleAn example


Current statusCurrent status

ABC supportABC support Collaboration using a server and P2PCollaboration using a server and P2P Ad hoc collaboration using DOLCLANAd hoc collaboration using DOLCLAN Hybrid collaborationHybrid collaboration P2P

CENTRALIZED


Current statusCurrent status

abc - ad-hoc collaboration - 24/03/2006 1 abc ad-hoc collaboration

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