Inleiding Telematica 6 16 mei 2007

1. Inleiding Telematica616 mei 2007 Prof. Dr. R.J. Meijer

2. Organisatorisch • Sheets asap op site • www.science.uva.nl/~rmeijer • Graag emailadres • 0653720517 • rmeijer@science.uva.nl • http://gene.science.uva.nl/~bbruin/

3. College 6, 24 mrt 2005

4. Application Application HTTP HTTP Application Program Interface (API) • Sockets zijn interfaces naar de TCP/IP protocol stacks op een computer • Applicaties worden “op” sockets gebouwd • Maar vrijwel niemand doet dat nu nog • Men gebruikt • Webservers • Applicatie Servers • die een groot (ste) gemene deel van Server ontwikkeling aanbieden TCP IP

5. Traditional Contemporary Future • Technologies for information exchange • Technologies for information exchange • Technologies for the abstraction of individual computers – aka middleware OSI Application Presentation Application Workstation Session Transport Middleware Link Data Link computer computer computer DNA sequencer DB 3d Super computer Physical Virtual Computer Telematics • Specifications of protocols between computers and/or telecommunication systems • Technologies for the abstraction of individual computers – aka middleware • Technologies to use the facilities of others

6. Webservices(from Webservice essentials, E.Cerami) • Web service • Any service available over the Internet • That uses a standardized XML messaging system • Alternatives • XML RPC (remote procedure call) • SOAP • HTTP Post/Get XML XML

7. i i i i i i Web and Grid services are designed to provide on-line services • Service oriented architecture • Implicit object oriented, component oriented virtualization concept Aggregation of Teaspoonproxies Proxy of the teaspoons Teaspoon Software Online Computer Program Proxy of the teaspoon Proxy of the Aggregation internet

8. Teaspoon Software Online wireless link computer and sensors i i i i i i internet Object oriented virtualization … • Step 1: Think and link the things • Build in a computer • Give that computer control • Link the computers (via the Internet) • Step 2: Create virtual “agent” for a group of things • That offers easy, controlled, service, to many “customers” via the internet • “the service of an online resource” • Forget about the individual things

9. … where in the third step the interaction between the resources is coordinated through software, via the internet • Step 3: Service integration and creation • Software integrates the services and interactions of various resources into a new service Caffeine advisor Teaspoon Software Online Human caffeine model Billing Software Telephone Company

10. Sensoren (en actuatoren) zullen overal aanwezig zijn. Op dit moment staan vooral de zelforganiserende draadloze (uitstrooibare) senornetwerken in de belangstelling

11. SensorWEb and Sensor networks

12. Popular Scientist Business What is a sensor? A small but very intelligent device that can measure something important Intriguing telecommunication and computing devices that can solve many problems Cheap things for mass market

13. Popular Scientist Business What is a sensor web? A group/swarm of small but very intelligent wireless devices that can measure something important and communicate adhoc with each other and with the sink that connects to the internet xxxxx= buzz word Intriguing telecommunication and computing devices that can solve many problems Cheap things for mass market

14. Popular Scientist Business What is a sensor network? A network and very many sensor webs and several applications at several institutions Application Application Application Intriguing telecommunication and computing devices that can solve many problems Network/Internet Intelligent infrastructures

15. Sensor Network Routing Romit Roy Choudhury and Pradeep Kyasanur (Some slides are based on Dr. Nitin Vaidya’s tutorial)

16. A Review of Current Routing Protocols for Ad Hoc Mobile Wireless Networks Elizabeth M Royer, Chai-Keong Toh

17. Mobile Ad Hoc Wireless Networks • Unreliable wireless medium • Mobile nodes • No central authority • Traffic patterns application specific • Energy constraints • More information in MANET Charter

18. Example Ad Hoc Network S E F B C D A G H I Nodes have unique identifiers Routing problem – find path between S and D

19. Classification of routing protocols • Table-driven (proactive) • Up-to-date routing information maintained • Routing overhead independent of route usage • Source-initiated (demand-driven / reactive) • Routes maintained only for routes in use • Explicit route discovery mechanism • Hybrid Protocols • Combination of proactive and reactive

20. Classification (cont.) Ad Hoc Routing Protocols Reactive Hybrid Proactive Source-initiated on-demand Table driven Hybrid ZRP WRP OLSR DSDV CGSR DSR AODV TORA ABR SSR

21. Table-driven Routing Protocols • Each node maintains a routing table • Contains routes to all nodes in the network • Changes to network topology is immediately propagated • Protocols differ in mechanisms used to propagate topology information

22. Destination Sequenced Distance Vector (DSDV) • Based on Bellman-Ford algorithm • Enhanced with sequence number to avoid loops • Fresher routes have higher sequence numbers • Optimizations added to reduce routing overheads – incremental data exchange, delayed exchange of updates

23. DSDV Example Routing Table of Node A A B C D Route information is exchanged periodically

24. Clusterhead Gateway Switch Routing (CGSR) • Nodes organized into hierarchy of clusters. • Each node has a clusterhead, selected using an election. • Nodes send packet through clusterheads. • Clusterheads communicate amongst themselves using DSDV. • Two clusters are connected through a gateway node

25. Wireless Routing Protocol (WRP) • Maintains multiple tables • Distance, routing, link-cost, etc. • Link change messages exchanged only between neighbors • Loop freedom using novel algorithm • Uses predecessor hop information

26. Other Table-Driven Protocols • Optimized Link State Routing Protocol (OLSR) – RFC 3626 • Optimization of link-state routing to wireless • Topology Dissemination Based on Reverse Path Forwarding (TBRPF) - RFC 3684 • Also based on link-state routing

27. Source-Initiated On-Demand Routing • Create routes only when needed • Routes found using a “route discovery” process • Route maintenance procedure used to repair routes

28. Ad Hoc On-Demand Distance Vector Routing (AODV) • Now RFC 3561, based on DSDV • Destination sequence numbers provide loop freedom • Source sends Route Request Packet (RREQ) when a route has to be found • Route Reply Packet (RREP) is sent back by destination • Route Error messages update routes

29. 4G sensornetwork support telecom infrastructure Pro environmentgroups Education Government Oil company Research institutes Information publishing Processing data to create information Data gathering Shared Resources. It is good practice that sensor networks serve many applications at several institutions. Technical: this enables changes, exploitation: this shares costs Common infrastructure

30. WAT NU ALS DE ICT ZELF EEN RESOURCE IS? Netwerk en IT wordenobjecten!

31. Internet IP PoP2 EVKC EVKC ISP EVKC NRC NRC EVKC EVKC PoP1 NRC NRC ADSL DSLAM PAN kabelverdeelkast SAN TAN Nu: Telefonie- en internet infrastructuur: groot complex, statisch. • 25 EVKC • 2000 NRC • 30 miljoen klanten • 20000 werknemers

32. Sensor networks will be large and complex too, but are dynamic. E.g. with disasters parts of the networks are destroyed and a immediate addaptation is required Next GNG mobile fixed network nodes - RESEARCH TOPIC 10 4 5 9 3 8 7 1 2 6 11 Storage Supercomputing

33. Virtualization of a network in UPVN Application Application Application Application NE NE NE NE Network Element Network Element Network Element Application Application NC NC NC NC Network Element AC AC AC AC

34. Network elements are PC’s that run a Free BSD operating system NE Service NC CollectionSupport ApplicationComponentmanager Application Component Collection AC AC AC AC AC packet injection AC packet injection IngressPacketFilter EgressPacketFilter IP Router / Forwarding engine NE’s expose webservice interfaces AC’s are SCPed on NE AC’s communicate with application via a message passing mechanism through NE webservice interface

35. UPVN allows the results of decades of computer science to handle the complexities of application specific networking. Mathematica Virtualized Network Service Webservices Collection Network Utility Service TokenTransaction UniformCostSearch Topology Network Component Collection NC NC NC NE NE NE

36. Use of Mathematica’s Combinatorica package to interact with real networks Shortest path, transactions, use of tokens: Initialisation: Needs["WebServices`"] <<DiscreteMath`Combinatorica` <<DiscreteMath`GraphPlot` Print["The following methods are available from the NetworkComponent:",InstallService["http:// localhost:3000/network_service/service.wsdl"]]; The following methods are available from the NetworkComponent: {GetAllLinks,GetAllElements,NetworkTokenTransaction} nodePath = ConvertIndicesToNodes[ ShortestPath[ g, Node2Index[nids,"192.168.3.4"], Node2Index[nids,"139.63.77.49"]], nids]; Print["Path: ", nodePath]; If[NetworkTokenTransaction[nodePath, "green"]==True, Print["Committed"], Print["Transaction failed"]]; Path: {192.168.3.4,192.168.3.1,139.63.77.30,139.63.77.49} Committed NE Discovery: Topology and visualization of the shortest path: n = GetAllElements[]; e = GetAllLinks[]; nids = Apply[Union,e]; Print["Network elements: ", n]; Print["Number of ports found: ", Length[nids]]; Network elements: {bigvirdot,virdot} Number of ports found: 16

37. demonstratie

38. Als netwerken objecten worden dan • Verdwijnt de C uit ICT • Telematica wordt Informatica!