1. ABC - Ad-hoc collaboration - 24/03/2006 1 ABC Ad-hoc collaboration

2. ABC - Ad-hoc collaboration - 24/03/20062 Agenda  Activity Based Computing (short) What is ABC?What is ABC?  The current hybrid architecture Current architectureCurrent architecture Pros. et. cons.Pros. et. cons.  P2P infrastructure based on DOLCLAN Peer-to-peer Distributed Shared ObjectsPeer-to-peer Distributed Shared Objects  Ad-hoc ABC collaboration StatusStatus

3. ABC - Ad-hoc collaboration - 24/03/20063 Activity Based Computing

4. ABC - Ad-hoc collaboration - 24/03/20064 Activity Based Computing

5. ABC - Ad-hoc collaboration - 24/03/20065 Activity Based Computing  Activity-based Collection of related services Collection of related services Many concurrent activities Many concurrent activities  Session migration The user’s session is distributed across the hospital The user’s session is distributed across the hospital Suspend – Resume Suspend – Resume Heterogeneous devices Heterogeneous devices  Collaboration 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 Awareness The computer adapts itself to the user’s context (PACS) The computer adapts itself to the user’s context (PACS)

6. ABC - Ad-hoc collaboration - 24/03/20066 The current architecture  Client-Server Easy to create Easy to create Performance Performance Scalability Scalability  Hybrid architecture Accountable Accountable Ephemeral Ephemeral

7. ABC - Ad-hoc collaboration - 24/03/20067 Hybrid architecture  Pros Concurrency control Concurrency control Late joining Late joining Security Security Membership Membership Invitations Invitations Synchronous collaboration Synchronous collaboration Asynchronous collaboration Asynchronous collaboration Failure detection / handling / repairing Failure detection / handling / repairing Discovery service Discovery service  Cons Disconnected collaboration Disconnected collaboration Ad-hoc collaboration (Anywhere) Ad-hoc collaboration (Anywhere)

8. ABC - Ad-hoc collaboration - 24/03/20068 Shortcomings  Ad-hoc collaboration No infrastructure No infrastructure Collaboration anywhere Collaboration anywhere Disconnected collaboration Disconnected collaboration

9. ABC - Ad-hoc collaboration - 24/03/20069 P2P infrastructure - DOLCLAN  Distributed Objects in Loose Coupled Local Area Networks

10. ABC - Ad-hoc collaboration - 24/03/200610 PDSO and groups  Peer-to-peer Distributed Shared Objects OID OID PDSO PDSO Group Group

11. ABC - Ad-hoc collaboration - 24/03/200611 Model View Controller

12. ABC - Ad-hoc collaboration - 24/03/200612 Syntax public distributed class DistributedPoint { //A distributed Point private distributed ephemeral int x; private distributed ephemeral int y;... }

13. ABC - Ad-hoc collaboration - 24/03/200613 Syntax public distributed class DistributedPoint : Observable { //A distributed x position private int x; public distributed ephemeral int X{ get { return this.x; } set { this.x = value; //Notify observers this.stateChanged(); } //A distributed y position... }

14. ABC - Ad-hoc collaboration - 24/03/200614 Syntax public void start(){ OID[] oids = EaterModel.getOIDs(); if (oids.Length > 0){ model = join EaterModel(oids[0]); } else { model = new EaterModel("MyGame",10); }... }

15. ABC - Ad-hoc collaboration - 24/03/200615 Syntax public distributed class DistributedStone : Observable {... public void merge(object netState){ //Cast the object to a DistributedStone DistributedStone netStone = (DistributedStone)netState; //The position never change, so thats up to date //Figure out if the stone has been eaten either offline or online this.Eaten = (this.Eaten || netStone.Eaten); }

16. ABC - Ad-hoc collaboration - 24/03/200616 An example

17. ABC - Ad-hoc collaboration - 24/03/200617 Current status  ABC support Collaboration using a server and P2P Collaboration using a server and P2P Ad hoc collaboration using DOLCLAN Ad hoc collaboration using DOLCLAN Hybrid collaboration Hybrid collaboration P2P CENTRALIZED

18. ABC - Ad-hoc collaboration - 24/03/200618 Current status