JXTA. Master 2 IFI: Peer to Peer. Julian Monteiro. Project Mascotte CNRS/INRIA/Univ. of Nice-Sophia

Transcription

1 JXTA Master 2 IFI: to Julian Monteiro Project Mascotte CNRS/INRIA/Univ. of Nice-Sophia

2 Acknowledgements Bernard Traversat, Project JXTA, Sun Microsystems Gabriel Antoniu, IRISA/INRIA Rennes SébasEen Monnet, LIP6 Paris Ian J. Taylor, Cardiff Univeristy UK and some other presentaeons on the web. 2

3 Outline JXTA Overview JXTA Architecture JXTA s JXTA Groups JXTA AdverEsements JXTA Pipes JXTA Protocols and Services JXTA Examples 3

4 JXTA: background Sun Microsystems by Bill Joy - the creator of vi - contributor of NFS - co- founder of Sun JXTA was first released in 2001 Last release in Nov JXSE 2.5 4

5 JXTA: Goal Build a small, lightweight pla`orm as the foundaeon for peer to- peer massively scalable network compueng jux ta pose - tr. v.: To place side by side, especially for comparison or contrast. 5

6 EvoluEon of Distributed CompuEng TCP/IP HTTP JXTA Client-Server Web-based Source: Sun Microsystems -to- 6

7 What is Project JXTA? JXTA is a open set of XML- based generalized P2P protocols to enable communicaeon and collaboraeon of devices. 7

8 A Generic Framework for P2P CompuEng Project JXTA defines a set of six protocols, which allow peers to: Discover each other Self- organize into peer groups AdverEse and discover network services Communicate with each other Monitor each other and the protocols do not require the use of any parecular: programming language operaeng system network transport Topology authenecaeon Security encrypeon model. 8

9 JXTA Interoperability: Any Pla`orm, Any Network MyJXTA (J2SE on Windows) JXTA Chat (MIDP) JXTA Virtual Network JXTA-C Shell (C on Solaris) 9

10 JXTA Virtual Network Project JXTA Virtual Network Virtual Mapping Physical Network Firewall TCP/IP HTTP Physical Network NAT 10

11 JXTA: Design Constraints 1. Interoperability Common language to talk to each other (XML) Sojware vendors tend to create specific code for their services e.g. file sharing, instant messaging, etc. - > incompaeble systems 2. Pla:orm independence programming languages e.g. C or Java system pla`orms e.g. Microsoj Windows and UNIX networking pla`orms (such as TCP/IP or Bluetooth) 3. Ubiquity implementable on every kind of device, e.g. PDAs, phones, sensors, consumer electronics appliances, network routers, desktop computers, data- center servers, storage systems future proof e.g. such technologies should be extended to new pla`orms e.g. mobile phones using J2ME 11

12 JXTA Enables P2P ApplicaEons Content Delivery Distributed storage and data sharing Search, indexing and file sharing Large scale distributed compueng P2P messaging and collaboraeon tools Entertainment 12

13 Outline JXTA Overview * JXTA Architecture * JXTA s JXTA Groups JXTA AdverEsements JXTA Pipes JXTA Protocols and Services JXTA Examples 13

14 s A peer Networked devices: Desktops, Laptops, PDA s, Mobile Phones, Bluetooth enabled devices, Server clusters, etc that implements one or more JXTA protocols Unique idenefier (UUID) e.g. urn:jxta:uuid e Addressable independently of its locaeon (firewalls, NAT) MulEple endpoint addresses (TCP, HTTP, etc.) types Minimal, Edge, Rendezvous, Relay, and Proxy 14

15 s ClassificaEon Edge s: Minimal: send/receive (without caching, without roueng) Full: send/receive + caching (without roueng) Super- s: Rendezvous: Maintains global indexes of resources Support a distributed lookup service Handles message broadcaseng Relay: Route messages between peers that do not have direct real network connecevity (e.g. firewall) Proxy: Provide support to minimal- edge peers to get access to all the JXTA network funceonaliees 15

16 Relay s CommunicaEon between peers behind firewalls Firewall Firewall A Super Request Message B Send Message Relay Message Super Receive Message Source: Sun Microsystems 16

17 Groups A colleceon of peers that agreed upon a common set of services Why? Provide a group idenety (common interest) Create secure & protected domains Scope peer operaeons (discovery, search, communicaeons) Enable monitoring GroupA NetGroup ID ID ID ID ID ID ID GroupB ID 17

18 JXTA Main Components : A JXTA node. A Rendezvous : a meepng place e.g. gateway for JXTA peers Group: a set of JXTA nodes who share a common interest Rdv. Rdv. 18

19 Messages Basic unit of data exchange (objects sent between JXTA peers) Ordered sequence of named/typed contents called Elements Contains its own roueng informaeon Contains any type of data: strings, byte arrays, documents, input streams XML and binary representaeons are used 19

20 Pipe: Virtual CommunicaEon Channel Pipes are virtual conneceons to exchange Messages Uni- direcgonal Asynchronous Unreliable Connect to services independently of their locaeons (must be in the same group) Transparent fail- over by reconneceng pipe endpoints Pipeline muleple services to form complex service (i.e., like Unix pipes) There are JxtaSocket and JxtaBiDiPipe for reliable conns. 20

21 Pipe Types Input Pipe Output Pipe Point- to- Point Pipe Connects exactly two peer endpoints together Receive Send Propagate Pipe Connects one output pipe to muleple input pipes Receive Receive Receive Send Receive 21

22 JxtaSocket and JxtaBiDiPipe BidirecPonal reliable communicapon channels Reliability Ensures message sequencing Ensures delivery Exposes message and stream interfaces Security JxtaBiDiPipe expose a message based interface Both are built on top of pipes, endpoint, and the reliability library 22

23 AdverEsements All JXTA resource is represented by an adveresement! group Pipe Service Content status Detailed specificaeon AdverEsements are XML documents <?xml version= 1.0?> <!DOCTYPE jxta:pipeadvertisement> <jxta:pipeadvertisement> <Id> urn:jxta:uuid e e3e </Id> <Type> JxtaUnicast </Type> <Name> TestPipe.end1 </Name> </jxta:pipeadvertisement> 23

24 AdverEsements (contd.) JXTA objects to adverese JXTA resources s, Groups, Services, Pipes, etc Represented as text documents typically in XML AdverEsement instances created via AdverEsementFactory Each adveresement published with a lifeeme (Eme- to- live) Enables deleeon of obsolete resources without requiring centralized control 24

25 JXTA Architecture JXTA ApplicaPons JXTA Services JXTA Community ApplicaEons JXTA Community Services SUN JXTA Services SUN JXTA ApplicaEons Indexing Searching File Sharing JXTA Shell Commands JXTA Core Groups Pipes Monitoring Security (authenecaeon, authorizaeon and on the wire) Any on the extended Web 25

26 JXTA Protocols Higher level protocols: Discovery Protocol (PDP) find peers, groups, adveresements InformaPon Protocol (PIP) - learn peers status/properees Pipe Binding Protocol (PBP) - bind to pipe endpoints Core protocols: Resolver Protocol (PRP) - send/receive search queries Endpoint RouPng Protocol (ERP) - find routes to a desenaeon (allows the implementaeon of roueng algorithms into JXTA) Rendezvous Protocol (RVP) propagate messages in a controlled fashion (message walkers, i.e. DHT) Protocols in JXTA: All protocols are provided as services in JXTA 26

27 JXTA Protocols Super Micro Core Protocols Source: Sun Microsystems 27

28 JXTA: Core Services Discovery Service Info Service Pipe Service Resolver Service Membership Service Access Service 28

29 Query PropagaEon Queries only propagated among rendezvous peers Edge peers only receive direct queries for their own adveresements Rendezvous peers self organize 29

30 Request PropagaEon via Rendezvous Super s 6. Query Resonse A 1. Push SRDI Index B Super 3. Query Super 2. Map and push index copy 5. Forward Query 4. Route Query Super 30

31 DHT- based Resource Discovery Overview: Edge peers publish indices of adveresements across Rdv network using Distributed Hash Tables (DHT) DHTs are maintained by Rendezvous peers Queries are directed to appropriate Rdv If not found, a walk of the Rdv web is performed Hash funceons are pluggable 31

32 Loosely- Consistent DHT s have high churn rate Maintaining a consistent distributed index outweight the advantages of having one Network crawling is expensive but does not have any maintenance cost Take a look at the project: JXTACh, they replaced this Loosely- Consistent version by a Chord DHT. 32

33 Rendezvous View (RPV) Each rendezvous peer maintains an ordered list of known rendezvous peer in the peergroup by their peer IDs No strong consistency mechanism is used to enforce the consistency of the RPV across all rendezvous Rendezvous periodically select random number of rendezvous from their RPV, and send them a random list of their known rendezvous 33

34 Publish adveresement 34

35 Search adveresement 35

36 Inconsistent view 36

37 Limited- range walker 37

38 Finding Rendezvous s Edge peers maintain lists of rendezvous peers Dynamic fail- over when conneceon fails Edge peers discover and cache Rdv adveresements Seeding Rdvs are used to bootstrap Auto- promoeon to Rdv if none can be found in Group 38

39 Outline JXTA Overview JXTA Architecture JXTA s JXTA Groups JXTA AdverEsements JXTA Pipes JXTA Protocols and Services * JXTA Examples * 39

40 Let's get started! Hello JXTA! Resource discovery Pipe communicaeon Discover and use a service 40

41 Hello JXTA! import public class SimpleJxtaApp { public static void main(string args[]) { try { // Create, and Start the default jxta NetGroup NetworkManager m = new NetworkManager(ConfigMode.EDGE, SimpleApp ); m.startnetwork(); Group netgroup = m.getnetgroup(); // Obtain the peer advertisement Advertisement adv= netgroup.getadvertisement(); //Get the discovery service DiscoveryService discovery = netgroup.getdiscoveryservice(); } //Publish the peer advertisement discovery.publish(adv); } catch (GroupException e) { e.printstacktrace(); } 41

42 Resource discovery Remote interface discoverylistener discoveryevent (DiscoveryEvent ev) discovery.adddiscoverylistener(this) discovery.getremoteadveresments( ) Local discovery.getlocaladveresments 42

43 Pipe communicaeon Receiver interface: PipeMsgListener pipemsgevent(pipemsgevent) pipeservice.createinputpipe(adv, Listener) Sender interface: OuputPipeListener outputpipeevent(outputpipeevent) pipeservice.createoutputpipe 43

44 JXTA Services Server Create a ModuleSpecAdverEsement Include a pipe adveresement Create the input pipe Publish the adveresement Read messages on the pipe (waitformessage) Client Discover the ModuleSpecAdverEsement Extract the pipe adveresement Resolve the pipe adveresement and create an output pipe Send a message on the pipe 44

45 JXTA Plataform ImplementaEons Java 2 Standard EdiEon (J2SE) the reference implementaeon Java 2 Micro EdiEon (J2ME) C for MIDP- 1.0 compliant devices such as cell phones, PDAs, and controllers Others: ObjecEve- C, Perl, Ruby, Python,.Net 45

46 JXTA Transport ImplementaEons TCP HTTP Reliable MulEcast 46

47 JXTA Community Over 2,700,000 downloads 120+ aceve projects 18,000+ members AcEve discussion groups Community acevely contribueng and integraeng technology 47

48 JXTA Technology Today Enhanced Network and J2SE Pla`orm Mature, stable, secure, scalable pla`orm. 2.0 spec, code, demos, docs, and tutorials on- line Public virtual network in place Mix of large and small companies, government and educaeon using technology for internal apps and product development JXTA- C and JXME implementaeons available Community Projects 48

49 JXTA Technology Tomorrow Focus on stability, scalability and security IntegraEon with web services New P2P services? 49

50 Some JXTA ApplicaEons Collanos Workplace : hup:// Kerika : hup:// JuxMem : hup://juxmem.gforge.inria.fr/ Shoal A Dynamic Clustering Framework : hups://shoal.dev.java.net/ JDDAC NetBEAMS Data Sharing With JXTA : hup:// NetBEAMS_Access_Services_Overview.pdf Boeing Selects Sun's JXTA Technology For U.S. Army Future Combat Systems : hup:// smi/press/sunflash/ /sunflash xml com : hup:// MyJxta2 : hup://download.java.net/jxta/jxta- jxse/2.5/myjxta/ Project SAXTA : hup://saxta.geog.umd.edu/ zimpro zudha : hup:// zimpro.zudha.com/ BBN SPIDAR: hup:// JavaOneJXTAPresentaEon.pdf 50

51 Links / Bibliography Home Page: hup://jxta.dev.java.net/ JXTA v2.0 Protocol SpecificaEon : hup://jxta- spec.dev.java.net/jxtaprotocols.pdf JXTA JXSE Programmers Guide 2.5 : hups://jxta- guide.dev.java.net/ Project JXTA: A Loosely- Consistent DHT Rendezvous Walker hup://research.sun.com/spotlight/misc/jxta- dht.pdf Free JXTA Book at hup:// book/ 51

52 Thanks! 52