eceg group. ispace room before ispace room after

ECEG Group

iSpace Room Before

iSpace Room After

Abstract

• Event Heap• Solution: ECEG

ECEG System Features

• Resource Discovery



• Generic Application Platform




• Remote Control




• Remote Control

• Instant Messenger

ECEG System – How to Use

ECEG System

http://2g1319.ssvl.kth.se/~csd2002-forumispace/download/eceg.htm



System Overview

Application

P2P Communication

Discovery

JXTA

TCP/IP

Wave LAN

BlueTooth

Infrared

Wave LAN

Transport layer solutions

• Event Heap• Jini• Jxta

• Definition– Transport layer’s responsibility is to define

how traffic should be sent over inter-networks

Event HeapA centeral event dispatcher, all the message goes through the event

heap server.

Jini

Establishes a distributed system by moving interfaces of objects around the network

LookupService

LookupService

ServiceProvider

ServiceProvider

ClientClient

JiniJini

LookupService

LookupService

ServiceProvider

ServiceProvider

ClientClient

JiniJini

LookupService

LookupService

ServiceProvider

ServiceProvider

ClientClient Service Object

Service Attribute

JiniJini

LookupService

LookupService

ServiceProvider

ServiceProvider

ClientClient

Jini

• Advantages– Simplicity.– Robustness.

• Disadvantages– Platform dependency.– IP based.

JXTA”A layered model solution for developing Peer 2 Peer

applications, consisting of protocols that are independent from underlying topology” -SUN

JXTA

Peer 2 Peer

Dynamic

Lightweight

Chosen Technology: JXTA

• Advantages– Interoperability.– Platform Independent.– Ubiquity

• Disadvantages– Under Development.– Inherently Chatty.

ECEG System

Application

P2P Communication

Discovery

Source Code• public void discoveryEvent(DiscoveryEvent ev)• {• Debug.trace("-> MyPeerGroupNeigborhood.discoveryEvent", 1);

• DiscoveryResponseMsg response = ev.getResponse();• int index = -1;• Peer peerTemp = null;

• try• {• String aResponse = response.getPeerAdv();

• /* First we can elicit what peer has published the advert, we can then• determine which groups it belongs to */• InputStream is = new ByteArrayInputStream((aResponse).getBytes());• peerAdvert = (PeerAdvertisement)AdvertisementFactory.newAdvertisement(• new MimeMediaType("text/xml"), is);• Debug.trace("Number of responses received from: " + peerAdvert.getName() + " is " +• response.getResponseCount(), 2);

• index = neighborhoodData.doesPeerExist(peerAdvert.getPeerID());

• Debug.trace("Peer Description: " + peerAdvert.getDescription(), 2);

• Enumeration enum = response.getResponses();

• if (index >= 0) // the peer exists• {• Debug.trace("Peer exists", 1);• neighborhoodData.setPeerAliveFlag(peerAdvert.getPeerID());• ParsePeer.parse(• (Peer)neighborhoodData.vectorManip.elementAt(index),• peerAdvert, enum, this, true);• Debug.writePeerHtmlFile(peerAdvert.getName());• ParsePeer.dealWithSubAdvertisements(enum, (Peer)neighborhoodData.vectorManip.elementAt(index), this);• Debug.trace("End of peer exists", 1);• }• else if (index < 0)• {• Debug.trace("Peer does not exist", 3);• peerTemp = new Peer();• neighborhoodData.addPeer(peerTemp);• ParsePeer.parse(peerTemp, peerAdvert, enum, this, false);• ParsePeer.dealWithSubAdvertisements(enum, peerTemp, this);• Debug.trace("End of peer does not exist", 1);

• discovery.getRemoteAdvertisements (null, DiscoveryService.ADV, null, null, 30, this);• discovery.publish(myPeer.pipeAdvertisement, DiscoveryService.ADV);• discovery.remotePublish(myPeer.pipeAdvertisement, DiscoveryService.ADV);• }• }• catch (IOException ioe)• {• Debug.error("An IO error occured!!");• Debug.error(ioe.toString());• ioe.printStackTrace();• }• catch (Exception e)• {• e.printStackTrace();• }

• Debug.trace("<- MyPeerGroupNeigborhood.discoveryEvent", 1);• }

Project Issues

• Project Scope• Project Plan

Adherence• Extra Frills:

– Mouse Sender/Receiver

– Instant Messenger– Dynamic IP Discovery– Inter iSpace

Communication

Problems Faced

• Team Member Loss• Tomorrow’s

Technology• Inter-Subnet• Peer Groups

Conclusion

• Wave LAN

• JXTA

• Layered Model

• Developed Application

• Future

Acknowledgements

• Li Wei

• Erik Eliasson

• Fredrik Kilander

• Teaching Team

Questions & Answers

?

eceg group. ispace room before ispace room after

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