外文翻译原文--无线传感器网络路由协议

1、外文翻译原文一无线传感器网络路由协议sensorroutingprotocols for wirelessnetworksbasil eteaelectrical enginccringloyola marymount university buetefiacomfaculty mentor s shankar sastryresearch supervisor jonathan sprinklegraduate mentortanya roostasummer undergraduate program in engineering at berkeley superb2004departm

2、ent of electical engineering computer sciencescollege of engineeringuniversity of california berkeleyrouting protocols for wireless sensor networksbasileteaabstractthis paper presents animprovcment on theimplementation of information routing capabilities in ad hocwireless sensor networks improving t

3、he protocolsused by eachsensor node can increase the networkslocalization and power conservation abilities furthermore using a more efcient algorithm will improve the overall effectiveness of the entire network in termsof power efciency using novel and creative schemesto generate shortest paths for

4、infonnation routing from sourceto destination nodes we have implemented anapproach to limit the incfeicncies of routing protocols usedby sensor networks for information transferiintroductionad hoc wireless sensor networks have the capacity to revolutionize the contemporary tech niceil arc neiofferin

5、g a more convenient means of communication this idea of infrastructure less networks can transformmany applications including mi litary strategy home security information transfer environment monitoringand surveillance this concept can initiate wave of wireless interaction that the world has not yet

6、 seena ad hoc wireless sensor networksan ad hoc wireless sensor network is a system of wireless nodes that dynamically seif-organize in randomnetwork topologies this allows internetworkinginareas wherecommunication infrastructureswere oncenonexistent 1 the nodes of these networks can col 1 aborate w

7、i th their neighbors to perform functions such asrouting localization time-synchronization and deitei aggrcgation however these networks have many complexproblems that need to be solved before this innovative idea comes into being such as power conservation andlocalizationb multi-hop wireless networ

8、ksmulti-hop wireless networksarc a type of ad hocwireless networks thisterm refersto theidea of theinformation beingtransferredhavingto travel throughmore that onelocation to reachi ts nal destinationbased onthe scheme ofitsnetworksalgorithm amulti-hop wireless network can becostly in terms ofpower

9、al so leach individual nodein a wirelessnetwork usual 1yrequires some complex scheme to manage itslocalization localization is the idea thateach node canapproximate its location by using algorithms to ndthe distance of itself fromitsneighbors these issues ofcomplicate thepower conservation and local

10、izationcoding schemes of many algorithms designed for the berkeley motesc berkeley motesin recent years university of california 一 berkeley has emerged as a leader in the technological advancementsof ad hoc wireless sensor networks researchers at uc berkeley have developed these motes they are aphys

11、ical interpretation of the wireless sensor net work an example of a mote is shown in fig 1tnfact berkeley has developed a test bedn whichmany of thesemotes rest on a nylon net sensing itssurroundingenvironmcnt furthcnnorcthe motes have seen muchadvancement overthe past yearsmicalsfig 2 shows the mot

12、es asthey have evolved fromto mica2dots thesize ofthe mica2dots hasdecreased to nearly the size of a quarter the sensor boards shown inthe appendix give the mote its sensingcapabilities these motes also use a progrcim board which is also shownwith a mote in fig 3the board is connected to the compute

13、r using the serial andparallel ports they not only program the motesbut also give the user the abil ity tolis ten toanentire network the system used by these motes is entirely written in tinyos an open-source operating system designed forwi reless embedded sensor networksthis work was supported by t

14、he national scienee foundation underthe summer undergraduate program for engineering researchat berkeley - information technology superb - tt 2004fig 1sample motefig 2 this gurc shows theevolution of the berkeley motesfig 3 this gure shows the a berkeley mote with a programming boardd tinyostinyos i

15、s an event-driven operating systcm intended for sensor networks with limited resources the tinyossystem libraries and applica tions are writ ten in nesc a new language for programming embedded systems nescis a version of c that was designed to handle the structuring and cxccution of tinyos in ncsc p

16、rograms arcbuilt out of components which are wired together to form whole programs the behaviors of these componentsare specied in tcrms of intorfaces these interfaces arc bidirectional they specify a set of functions to beimplemented by their providers and users the components are linked together b

17、y their interfaces nesc expectsthat code will be generated by whole-program compilers and is based on run-to-completion tasks and interrupthandlers which may interrupt tasks and each other to help with the struggles of nesc tinyos has a simulatorthat provides abstractions of reeil world phenomena su

18、ch as bit error 2e tossimtossim is a discrete event simulator for tinyos sensor networks instend of compiling a tinyos applicationfor a mote users can compile it into tossim which runs on a pc tossim builds directly from tinyoscode this allows users to debug test and analyze algorithms in acontrolle

19、d cvnvironmcnt tossim capturesthe behavior of tinyos at a very low level it simulates that network at the bit level simulates each individualadc ccipture and every interrupt in the system however though tossim captures tinyos behavior at a verylow level code which runs in a simulation might not run

20、a on real mote although tossim times interruptsaccurately it does not model execution time tossim also does not model radio propagation nor does it modelpower draw or energyconsumptioninstead it providesradio abs treicti on of in depende nt bit errors betweennodes and can be adjusted to add armotati

21、ons to components that consume power to provide information onwhon their power state changes eg turned on or off 3 tossim also has many applications that can be usedto accurately simulate these motesf tinyviztiny viz allows toss im simula tions to have cin extensible graphical user interface for deb

22、ugging visualizingand intoraction tinyviz can easily trace the execution of tinyos apps set breakpoints visualize radio messagesand manipulate the virtual position and radio connectivity of motes 4 al so tinyviz al lows you to write yourown modules to visualize data or interact with the tunning simu

23、lation among many other features tossimal so uses an oscilloscope a sensor network topology window and also a serial forwarder some of whicharc shown in fig 4fig 4 oscilloscope and serialforwarder tools used in tossimiimethodologya problem statementthe purpose of this research is to design a shortes

24、t path routing algorithm for use with the berkeley motesthe objective of the shortest path touting algortihm is nd the shortest path from one node to the next basedon the information packets beginning and nal locations the nodes of thisnetwork willhave asingle patht hatt hey willdirec t inf onus tio

25、ndow nbased on thedestination address this single path is designed to bethe packcts shortest path which is why it would be most bcnccial to travel on that route one problem thatmust be avoided is that of free-looping this is when a node in the alogorithm that is on the shortest pathmalfunctions and

26、the information packet is sent in a continual circle never reaching its nal destination alsoshortest path routing algori thms are usual ly simple therefore using it w订1 most likely reduce the complexityof the overheadb shortest path routingdesigning an algorithm to implement shortest path routing be

27、tween nodes for informeition tremsfcr is a verycomplex matter the goal of this algorithm is to efciently nd a path from one node to another using the leastamount of hops possible in a multi - hop wireless net work there arc many things to take into considerationbefore a shortest path routing algorit

28、hm can function power conservation and memory mem agement createcomplexities that make devising an efcient route selection algorithm rather difcult however the researchpresented implements a possible solutionfig 5 node table and structuresc shortest path algori thmthe essence of this shortest path a

29、lgorithm rests in its ability to create a table and tree like structure imaginceach node being organized in a tables by their addresses and na destinations as shown in fig 5based on the destination address of the informationpacket each node in this table also has a tree likestructure that describes

30、a shor test path from which t hey can det ermine which node to send the packet to nextas shown in fig 6fig6tree-1ike structuresin theory each node mai nt ains a table sorted by the destination address of the packet that lists the nexthop address there is a neighbor table that lists al 1 the nodes as

31、 wel 1 as a node table that lists the next hopand dcstineition inforniationd advantageswhi 1 e this may seem costly in terms of memory management itprovides a simplistic method for choosingwhich node needs to be on standby at all times thereby improving the power conservation of the networkthis meth

32、od also gives the system a localization feature each node will know its location in proximity to itsneighborsin mos t sensor net works it is comm on prac ticc to use a base station node to distribute and relay informationto its surrounding peer nodes with a base station system in order to get the in

33、formation packet to its destinationa node must rst send the packet to the base station node as shown in fig 7 the base station is the onlynode that can send to a nal destination addressfig 7samplebascstation strueturcthe beauty of the design in this research is that any node canimmediately direct th

34、e information to any othernode at any time each node has equal bearing and status in this net workstructure imagine a node structuresimilar to that in fig 8fig8base-station disadvantagein a base station sys tem if the node at address 2wanted to send information to the node at address 0it would have

35、to send the packet to the base station at node address 1 rst in the shortest path system thenode at address 2 can direc tly send the information to the node at address 0 showing an improvement ofefeicncy between those two models this also crcates a more safe and secure network for example in abase s

36、tation system if the base station node malfunctions that immensely affects the productivity of the othernodes however in the node structure described in this research the malfunction of one node mildly affectsthe efciency of its counterpartssome networks also use an algorithm that sends the informat

37、ion packet to all of its neighbors no matter whatthe destirmtion is each of the nodes that just received this information would then send the same informationpacket out toeachof theirncighborsthisprogressioncontinues untilthepacket hasnally reacheditsdestination thisalgorithm is knownas oodingunlike

38、this oodingapproach the shortest path algorithmof this research eliminates this inefcient network behavior directinga packet down one single pathe disadvantageslike most algor it hms t his shor test path scheme does have its disadvantages being that each node maintainsa route structure to each diffe

39、rent destination address this system uses a lot of memory which hinders theoverall efciency of the network also this design assumes a static network structure it would not be nearlyas effective in mobile or hybrid systemsf codingthe coding of tinyos was done in nesc a programming lemguage based on t

40、he c programming languagefour tables had to be dened in the header lc for the necessary structures of this algorithm to be created theyinclude a node entry table a node table a neighborentry table and a neighbor table the node entry table contained the node address and the address of the next hop th

41、e nodetable organized each of the node tableentries by a nal destination address the neighbor entry tablecontained a node address as well a node tablefor each node lastly the neighbor table organized each of the neighbortable entry by node addresses toslocal address in the route select module a stat

42、icnetwork of nodes is formed here there are giventheir shortest path structures as well as their table entry locationsample code of this process is shown in figfigsample codealso in the route select module afunctionnamedgetparcnt is called that is passed through the actualfps message from this the n

43、al destination ciddress is gathered based on the destination address from thefps message an algorithm dctcrmines the shortest route for the information packet by searching through thetables and structures created a sample of this code is included in fig 10fig10sample codeafter it nds this value it w

44、i 11 return the address of the next hop that is on the shortest path then thisaddress is then placed in the appropriatc loceition in the strueturc of the message this message the gets placedon the send queue dequeued and sent and then received by the node at the next hop address this cyclerepeats un

45、til the information packet has reached its nal destination111resultsa tossimusing the tossim application of tinyos the shortest path algorithm was simulated tosstm was used as avery helpful debugger and also gave in sight on the code procedures before simulating the algorithm debuggingstatements wer

46、e put in to see the processes of the program the algorithm was then simulated with six motesand the infonneition packet was given a nal destination address of vc nodes had addresses zero through vethe simulation cycled through each node as the source address modeling every individual circumstanee us

47、ingtossims debugging window the packet appeared follow the direction of a node neighborhood structure thisstructure is shown in fig 11fig 11nodeneighborhood structurefor exampl e whe n the packe t origins ted at node address 0 its nexthop address would be node address1 then node address 3 and then n

48、ode address 5 its nal destination however if the node originated at nodeaddress 4 then the packets next hop address would be node address 3 then node address 5 its nal destinationb tinyvizin addition to tossim tinyviz was used to gain insight about the code processes tinyviz was actuallyused to visu

49、alize the movements of the information packets aniongst the nodes in this simulation a captureof this appl i cat ion in action is shown in fig 12similar to tossim t his illustrates a node neighborhood structure of the simulation each line representsthe path that a packet would take if it has already

50、 been sent or if it was about to be sent this visualizationcan be described by the same example that was explained earlier in this sectionivdiscussionbased on the static node neighbor structures given to the system beforehand the results received fromsimulati on were very much expected the route of

51、the information packet from each node was identical tothe node structures and trees dened at an eeirlier time in the program in fdct the gure used to display thenode neighborhood strueturc in the tossim example of the resuits section was the same node neighborhoodstructure illustration used to origi

52、nally create the node tree of a nal destination address equal to ve thereforethe output of the simulation was exactly what was needed for the algorithm to be successfulfig12simulation in tinyvizvconclusions and futureworksa conclusionstinyos is a very extensive and complex system it has manyapplicat

53、ions andtools that need to be studiedhow they willsoon change the world thisproject requiresthis research t learnedhowto usemost ofthetossim applicationsandhow toprogramin tinyos usingbefore onecan fully understandthe entire system doingnescalso learned about motenetworks anda lot of time and effort

54、 1 went through a lot ofpain trying to get some of the tossim applications running and programming in tinyos however because1 went through this pain 1 learned a lot more than 1 probably would have been had someone else just told mebeen from this project i helped contribute meaningfulcode that might

55、one day serve a purpose in the adhoc wireless network technical arena i hope my code can help others who are seeking ideas for a shortestpath algorithmas of today the average person would probably look at a mote or node of a wireless network and consider itharmless however these motes have the capac

56、ity to develop into many things especially when they are beingused developed by our military these motes can turn into a rather large ethical problem one day they willprobably be small enough to live inside of a human body having the motes sense the typical bodi1y functionsand movements of a human i

57、nfringes on privacy and human rights laws lets hope that the dem gers of thisnew technology will be averted before it gets to this levelb future worksif i had more time i would have wanted to put in a link estimation scheme into my shortest path algorithmthis would have allowed the node system to choose its path based on the strength of a signal it recieved fromits neighbor in t his scheme the n odes estimates how far away their neighbors are bas