Indonesian Journal of Electrical Engineering and Computer Science V ol. 4, No . 3, December 2016, pp . 486 498 DOI: 10.11591/ijeecs .v4.i3.pp486-498 486 GRPW -MuS: Geographic Routing to Multiple Sinks in connected wireless sensor netw orks Y assine Sabri STIC Labor ator y ,Chouaib Doukkali Univ ersity , B .P: 20,El J adida Morocco e-mail: sabr iy assino@gmail.com Abstract Multiple sinks routing is en visioned as a possib le solution to the bottlenec k research prob lem in Wireless Sensor Netw or ks (WSN). In addition to f ocusing on minimizing the energy consumption in a WSN, it is also equally impor tant to design routing protocols that f air ly and e v enly distr ib ute the netw or k tr affic; in order to prolong the netw or k lif e time and impro v e its scalability .In this paper w e present an enhancement to the GRPW a lgor ithm f or wireless sensor netw or ks . P erf or mance of GRPW algor ithm algor ithm depends hea vily on single sink position , w e propose a protocol called GRPW -MuS ( Geog r aphic Routing to Multiple Sinks in connected wireless sen sor netw or ks) based on Multiple Static Sinks , w e modified the e xisting sink location pr iv acy protection scheme b y dividing nodes in the netw or k containing m ultiple sink into diff erent le v els in which real pac k ets are f orw arded to sink belong to corresponding logical le v els and the inter mediate node gener ating f ak e pac k ets and sending it to f ak e sinks . Usin g OMNET++ sim ulation and the MiXiM fr ame w or k, it is sho wn that proposed protocol significantly impro v es the rob ustness and adapts to r apid topological changes with m ultiple mobile sinks , while efficiently reducing the comm unication o v erhead and the energy consumption. K e yw or ds: Wireless Sensor Netw or k (WSN), Routing, Multiple Sink, Localization, Geog r ap hic Routing Cop yright c 2016 Institute of Ad v anced Engineering and Science . All rights reser v ed. 1. Intr oduction A Wireless Sensors Netw or k (WSN) contains a set of sensors wh ich comm unicate to tr ansmit inf or mation about specific detections . A wide r ange of monitor ing applications ha v e al- ready been identified such as r isk detection on industr ial sites , protected and reser v e areas , intelligent tr anspor tation , and underw ater monitor ing [1, 2, 3] . Designing a WSN in v olv es tw o main le v els of decisions: oper ational and str ategic. In the conte xt of WSN, the oper at ional le v el is usually related to protocols , netw or k issues , comm unication policies , and tr affic loads and their distr ib ution; while the str ategic le v el addresses decisions ab le to better cope with some issues lik e minimizing the energy consumption, reducing the tr affic , balancing the netw or k load, enhancing the reliability , maximizing the netw or k lif etime , f or instance . In this study , w e f ocus on a str ategic and theoretical optimization prob lem occurr ing in the design of WSN. Data to the sink can be tr ansmitted via single hop or m ulti hop comm unication. All the sensor nodes can use single hop comm unication b ut in long distance tr ansmission, the energy consumption is m uch higher in tr ansmission as compare to processing and sensing tasks . T r ans- mission energy dominates the o v er all energy used in comm unication process . The requirement of energy goes on increasing with the increase of distance [4, 5]. Theref ore , it becomes necessar y to reduce the energy consumption and to enhance the netw or k lif etime . Theref ore , it is pref er ab le to use shor t-r ange m ultihop comm unication. In m ulti hop comm unication, all nodes comm unicate with each other using wireless channels without need of an y control str ucture and common infr as- tr ucture . Nodes cooper ate with each other to f orw ard the data and one or more nodes ma y pla y the role of re la y nodes (RN) [35]. Multi hop comm unication is the promising solution to increase netw or k co v er age and throughput. T r ansmission po w er of the senor nodes can be reduced to tr ansmit the data at the shor t distance and to reduce the interf erence among the signals . This is adv antageous in ter ms of spatial reuse of frequency . But a node pla ying the role of RN can Receiv ed J uly 9, 2016; Re vised October 21, 2016; Accepted No v ember 12, 2016 Evaluation Warning : The document was created with Spire.PDF for Python.
IJEECS ISSN: 2302-4046 487 deplete its energy ear lier than other nod es so this prob lem should be e xamined and tac kled b y the routing protocols . Man y diff erent technologies are under e xplor ation lik e fix ed rela ys (Rela ys that are not connected to the bac kbone of the netw or k), mo v ab le rela ys (Rela ys , which ag ree to tr ansmit the pac k ets of each others) and h ybr id rela ys (Rela ys , which are fix ed b ut are situated on the body of mobile objects). The use of rela y nodes is v er y beneficial in ter ms of scheduling, interf erence management, netw or k lif etime , adaptiv e modulation etc. Due to adv antages of m ulti hop comm unicatio n, man y researchers ha v e de v eloped rela y based routing protocols and in fu- ture , it can be considered vital to giv e attention to shor t-r ange comm unication where po w er le v els of nodes can be controlled. Man y protocols f alls under the categor y of m ulti hop comm unication. Se v er al w or ks in the liter ature b ur y the optimization issues into sim ulations which are done to solv e oper ational issues , with no f or mal definition of the corresponding optimization prob- lem. As a co nsequence , the proposed solutions ma y not proper ly handle the core of the opti- mization prob lem since optimization is a desired f eature and not the main f ocus . In v estigating the optimization prob lems in v olv ed in WSN allo ws to understand its comple xity and impro v e the control, the management and the design of WSN. Here , the bib liog r aphical re vie w main ly f ocuses on the w or ks dedicated to optimization prob lems f or WSN using m ulti-sin k . Rather than being e xhaustiv e , w e descr ibe w or ks strongly related to our main concer ns , i.e . to better understand the core of optimization prob lems in v olv ed in a WSN. 2. RELA TED W ORK AND B A CKGR OUND Wireless sensor netw or ks (WSNs) ha v e receiv ed significant attention due to their poten- tial use in se v er al diff erent real-w or ld application s [6, 7, 8]. T o increase the capabilities of such applications , the under lying WSNs are being enhanced with m ultiple sinks sensors that can to collect data from diff erent sensor nodes , theref ore data collection is impo r tant issue in wireless sensor netw or k. This ne w f or m of WSNs is kno wn as Routing Wireless Sensor Netw or ks with Multiple Sink [9]. The most widely kno wn proposal is [10][11], b ut se v er al other geog r aphic rout- ing schemes ha v e been proposed [12] One of the k e y challenges in geog r aphic routing is ho w to deal with dead-ends , where g reedy routing f ails because a node has no neighbor closer to the destination; a v ar iety of methods (such as per imeter routing in GP SR/GFG) ha v e been proposed f or this . More recently , GO AFR [13] proposes a method f or routing appro ximately the v oids that is some asymptotically w orst case optimal as w ell as a v er age case efficient. Geog r aphic routing is scalab le , as nodes e xclusiv ely maintain state f or their neighbors , and suppor ts a full gener al an y- to-an y comm unication patter n without e xplicit route estab lishment. Ho w e v er , geog r aphic routing requires that nodes kno w their location. While this is a natur al assumption in so me settings (e .g., sensor net nodes with GPS de vices), there are man y circumstances where such position inf or ma- tion isn’t a v ailab le .are most often require inf or mation about the position of their v oisins to function eff ectiv ely .Or , this assumption is f ar from the reality .The other , the localization of protocols , used as a preliminar y step b y geog r aphical routing protocol are not necessar il y precise . F or e xample , in [14],the authors proposed localization methods with which sensors deter mine their positions with a r ate of less than about 90% positioning in large scale . or , if a node that does not kno w its location, the node r isk of ne v er comm unicate with other node of netw or ks ,and no inf or mation will be tr ansmitted to the user and the base station ne v er kno ws that node . As a gener al wireless comm unication pr inciple , sensor nodes ha v e a maxim um tr ansmis- sion r ange . Theref ore , to route data to the sink node , a m ultihop tr ansmission str ategy is adopted. In gener al, the energy consumption of sensor nodes ne xt to the sink is higher compared to the one of other sensor nodes in the netw or k. This is due to the f act that the netw or k tr affic is un- e v enly distr ib uted. Consider ing their position ne xt to the sink node , most of the netw or k tr affic passes through the sinks neighbour nodes . This eff ect consider ab ly reduces the netw or k lif etime as the energy of the sensor nodes ne xt to the sink r apidly depletes resul ting in no possibility to reach the sink2. This eff ect is ref erred to as the bottlenec k prob lem and is accentuated as the netw or ks scalability increases in ter ms of n umber of nodes . The bottlenec k prob lem is accentu- ated in large-scale netw or ks because of the man y-toone netw or k tr affic patter n which increases GRPW -MuS: Routing to Multiple Sinks in WSNs (SABRI Y assine) Evaluation Warning : The document was created with Spire.PDF for Python.
488 ISSN: 2302-4046 the energy unbalance in WSNs with a single sink node . T o pro vide a longer lif etime while increasing m ulti-sensor y data collection r ates in WSNs , the research comm unity has e xploited the use of m ultiple sinks [15, 16, 17, 18]. m ultiple sinks can pro vide m ultiple alter nativ e routes from a source node to one of the interconnected sink nodes . This can shor te n tr ansmission distances and theref ore reduce the netw or k energy cost. Since sensor nodes pla y the dual role of both e v ent detectors and data routers , the larger the n umber of hops in v olv ed in the routing of data pac k ets to the sink, the g reater are the o v erheads e xper ienced, leading to higher energy cost. Ho w e v er , there are still se v er al challenging issues that need to be fur ther in v estigated in the conte xt of v ar ious applications of Routing Wireless Sensor Netw or ks with Multiple Sink [19]. One impor t ant implied assumption behind the data collection mechanisms using mobile sinks is that the collected data m ust be dela y-toler ant as the collection dela y is bounded b y the ph ysical distances and the speed of the mobile sinks . Clear ly , this whole approach w ould not be appropr iate when w e need to collect real-time data, f or which ne w approaches need to be de v eloped as w e are currently in v estigating in a related w or k [20, 21]. F or monitor ing applications that are ab le to perf or m their e xpected functionalities as long as the data tr ansmission is done within hours or min utes , then w e can consider mobile sinks . In such applications , to mak e better analysis and decisions , w e need to get almost all of the data from sen s o r nodes to the base station (i.e ., pro vide a high deliv er y r ate) while minimizing the collection dela y as m uch as possib le . In dense netw or ks , lif etime can be maximiz ed b y creat ing co v ers , i.e ., g roups of sensors that are activ e at the same time . This str ategy has been pro v en to be efficient in se v er al applica- tions of WSN [22, 23]. F ollo wing this id ea, decomposition approaches as column gener ation (CG) ha v e been largely used to identify and create schedules f or the co v ers . As w ell as in the classi- cal implementation, CG decomposes the prob lem into a restr icted master prob lem (RMP) and an auxiliar y prob lem (AP). The f or mer optimiz es the lif etime using an incomplete set of columns , and the latter is used to identify profitab le columns . In this paper w e propose an enhancement to the GRPW algor ithm based on scheduling techniques that allo w the sink node to send its position in a planned manner to suppor t a m ulti sinks ba sed on a logical par tition. W e propose a m ulti sinks with limit path in the edge of site which sensor nodes are scattered there . 2.1. Motiv ation In this paper w e present a ne w method f or m ultiple sinks enhancement based on the pre- vious GRPW a lgor ithm (Geog r aphic Routing Protocol W ashbasin). as basis f or an in v estigation on impro ving the deplo yment of a netw or k. GRPW is a geog r aphical routing protocol f or Wireless Sensor Netw or ks (WSN) ensures a load balancing, minimizing energy consumption and the r ate of message deliv er y f or v er y lo w po w er netw or ks and uses a routing policy with logical le v els , inspired fr om the w ater flo w in a w ashbasin . GRPW requires kno wledge the static single sink position which is considered as par ameter f or initialization of the netw or k to constr uct the logical le v els topology . By changing these par ameter a tr ade off is made betw een an o v erhead in the n umber of tr ansmissions used to setup routing inf or mation in the netw or k and an o v erhead in the n umber of tr ansmissions used f or sending the quer ies . In order to set these par ameter , the single sink node position has to be kno wn bef ore deplo yment. If GRPW is initializ ed with m ultiple sink par ameter then it will not be efficient and can in some cases be outperf or med b y a simple protocol such as classic flooding. In man y cases the n umber of e v ents or quer ies cannot be e xpected to be kno wn in adv ance . As a consequence , GRPW will not alw a ys be an at tr activ e routing protocol. 2.2. Or ganization W e ha v e organiz ed this paper in the f ollo wing w a y: Section II descr ibes the pre vious w or k. In this section w e will f ocus on GRPW which is t he basis f or our e xtension. In Section III w e descr ibe our algor ithm and the implementation of it. Section IV descr ibes the sim ulation details of our algor ithm and the results obtained are presented in Section V . In Section VI results are discussed and conclusions presented. IJEECS V ol. 4, No . 3, December 2016 : 486 498 Evaluation Warning : The document was created with Spire.PDF for Python.
IJEECS ISSN: 2302-4046 489 3. GRPW algorithm Se v er al papers ha v e been pub lished about routing in WSN. In this section w e will f ocus on introducing the GRPW Routing approach as this is the f oundation f or our w or k. F or a more elabor ate descr iption to GRPW please ref er to [24]. GRPW that ea c h node can get its o wn location inf or mation either b y GPS or other location ser vices [25][26] . Each node can get its one-hop neighbor list and their locations b y beacon messages . W e consider the topologies where the wireless sensor nodes are roughly in a plane . Our approach in v olv es three steps: Lev el 0 Lev el 1 Lev el 2 Lev el 3 Lev el 4 SB ( sink ) Figure 1. Illustr ation of GRPW routing netw or k le v els 1. The distrib ution the immobile sink posi tion to all sensor s netw orks: In the first step ,The comm unications in this step are made in three steps: When a node w ants to tr ansmit the sink position to its neighbors ,it first emits AD V message containing the location of sink. A node receiving a message AD V . If interested b y this inf or mation, it sends a message REQ to its neighbor . In Receiving a message REQ, the tr ansmitter tr ansmitted to the node concer ned the sink position in a D A T A message . 2. Construction of logical le vels: In this step the node netw or ks deter mine its le v el of be- longing through the sink node position,each node u w ell localiz ed, calculate its le v el based on the receiv ed position of sink in the Phase 1 ,with which u calculates the distance d uS ink which separ ates him with the sink node .the le v els is calculated so that the width le v el be constant is less than and in v ersely propor tional to the density of netw or ks . The le v el l of the node u defined b y: Lev el u = f l 2 N = d uS ink l d uS ink + 1 g Set of the neighbor nodes that are w ell localiz ed and which belongs to the same le v el as u : L N ( u ) = f v 2 N ( u ) =Lev el u = Lev el v g Set of the neighbor nodes that are w ell localiz ed and which belongs to the higher le v el than u : L + N ( u ) = f v 2 N ( u ) =Lev el u = Lev el v 1 g GRPW -MuS: Routing to Multiple Sinks in WSNs (SABRI Y assine) Evaluation Warning : The document was created with Spire.PDF for Python.
490 ISSN: 2302-4046 Set of the neighbor nodes that are w ell localiz ed and which belongs to the lo w er le v el than u : L N ( u ) = f v 2 N ( u ) =Lev el u 1 = Lev el v g 3. Data f orwar ding : The routing decisio n is done in our approach in three modes , depending on dispoinibilites neighbor ing nodes and of their le v el of belonging: the Ev en F orw arding , Anter ior F orw arding and the Rear F orw arding (respectiv ely called EF , AF and RF). In the first mode AF ,GRPW constr ucts a route tr a v ersing the nodes of the source to the destination which each node receiving a pac k et DataP ac k et with the mode of tr anspor t AN- TERIOR FOR W ORD , will mo v e to w ard the inter mediate node in its co v er age area what in bef ore , the inter mediate node select among the neighbor ing node using a lookup function. Lookup function is used b y a node in order that he can deter mine the ne xt hop to reach the ne xt le v el, to deter mine the ne xt hop function, lookup based on the pr inciple of Round Robin (RR). In the second mode EF , on account of the frequent f ailures of nodes , the mobility of nodes or policy scheduling of activities used, disconnecti ons can occur in the netw o r k gen- er ates , so , what are called holes in this situation, GRPW will change the routing mode to EVEN FOR W ORD to reroute the pac k et in EF mode and to o v ercome the v oid case . In the third mode RF , GRPW reroute the pac k et DataP ac k et, who w as f ailed in AF and EF , RF f act sends a pac k et to the lo w le v el L N () b y seeking the ne xt hop among neighbor ing based on the lookup function. RF is leaning on same techn ique used in EF , f or a v oids the routing loop w e saf eguard the sets of node tr a v ersed b y the pac k et DataP ac k et in a v ector-type str ucture 4. GRPW -MS: Adaptive Routing a Mobile Sink in WSNs Let us no w consider the use of GRPW in a sensor netw or k with static nodes and a single static sink. If the sink mo v es , its vir tual le v el will change , and the messages routed to the old coordinates will not reach the sink. A simple solution w ould be to no tify each nodes about the sinks ne w coordinates . This solution, ho w e v er is e xpensiv e in ter ms of the n umber of messages , and the corresponding energy consumption. The GRPW -MS algor ithm tak es an idea which had been successfully applied to geog r aphical routing to reduce the n umber of update messages necessar y to maintain routability in conte xt of m ultiple sinks . The gener al idea is that as long as the sink mo v es inside a limited local le v el area, the nodes outside that le v el area will not be notified about the sinks mo v ement. The routing will rely on the nodes at the per ipher y of the le v el area to f orw ard the messages to the the closest sink which belongs to its area. 4.1. GRPW -MuS defines the f ollo wing o verlapping categories of nodes In Figure 2 GRPW -MuS defines se v er al special nodes and area types: An inter nal nodes has all its logical address belonging to the same area sink . An area border noeud is a noeud that connected at one or more areas sink . It is considered a member of all areas sink it is connected . An ABN k eeps address of all sink where it belongs in memor y , one f or each area to which that node is connected. An area border noeud (ABN) is a noeud that connected at one or more areas sink . It is considered a member of all areas sink it is connected . An ABN k eeps address of all sink where it belongs in memor y , one f or each area to which that node is connected. A bac kbone area sink has a link to the bac kbone area. Each node has an identifier . This identifier m ust be estab lished in e v er y GRPW -MuS in- stance . If not e xplicitly configured, the highest logical address will be duplicated as the IJEECS V ol. 4, No . 3, December 2016 : 486 498 Evaluation Warning : The document was created with Spire.PDF for Python.
IJEECS ISSN: 2302-4046 491 Lev el 0 Lev el 1 Lev el 2 Lev el 3 Lev el 4 Source Designated Sink (DS) S I N K secondar y S I N K secondar y inter nal node Bac kbone area sink Area border noeud Area border noeud Figure 2. Illustr ation of GRPW -MuS routing netw or k le v els router identifier . Ho w e v er , since the router identifier is not a logical address , it does not ha v e to be a par t of an y area in the netw or k, and often isn’t to a v oid confusion. 4.2. GRPW -MuS Algorithm A designated Sink (DS) is the sink node elected among all nodes , ge ner ally assumed to be a m ultihop netw or k. The basic neighbor disco v er y process (Hello), DS election (pr ior ity). The DR is elected based on the f ollo wing def ault cr iter ia: If the pr ior ity setting on an GRPW -MuS node is set to 0, that means it can NEVER become a DS When a DS f ails and the BDS (Bac kup Designated Sink). tak es o v er , t here is another election to see who becomes the replacement BDS . The node sending the Hello pac k ets with the highest pr ior ity wins the election. If tw o or more nodes tie with t he highest pr ior ity setting, the router sending the Hello with the highest NID (node ID) wins . Usually the node with the second highest pr ior ity n umber becomes the BDS . The pr ior ity v alues r ange betw een 0 - 255,[14] with a higher v alue increasing its chances of becoming DS or BDS . If a hig her pr ior ity GRPW node comes online after the election h as tak en place , it will not become DS or BDS until (at least) the DS and BDS f ail. If the current DS ’goes do wn’ the current BDS becomes the ne w DS and a ne w election tak es place to find another BDS . If the ne w DS then ’goes do wn’ and the or iginal DS is no w a v ailab le , still pre viously chosen BDS will become DR. In GRPW algor ithm, SINK secondar y cannot compute distances when a designated Sink (DS) sends a message b y using distance estimation techniques SumDIST . This method is the most simple solution f or estimating distances to DS . It adds r anges encountered at each hop dur ing the netw or k flood. Each DS sends a message including its identity , coordinates and path length initializ ed to z ero . Whe n a node receiv es this message , it calculates the r ange from the sender , adds it to the path length and broadcasts the message . Thus , each SS obtains a distance estimation and posit ion of anchors . Of course , only the shor test distance will be conser v ed. Sum-dist is v er y simple and f ast. Moreo v er , little computations is required. A dr a wbac k of Sum- dist is that r ange errors are accum ula ted when distance inf or mation is propagate d o v er m ultiple hops . After this phase , Second calibr ation allo ws to con v er t distances into a r adius of the area representing its siz e . This con v ersion consists t o divide the estimated distance with the n umber of all sinks . GRPW -MuS: Routing to Multiple Sinks in WSNs (SABRI Y assine) Evaluation Warning : The document was created with Spire.PDF for Python.
492 ISSN: 2302-4046 After this logical netw or ks reconstr uction ,each sin k estab lishes its area based on the sink DS position. The routing of captured data be perf or med within each z one belonging to each node using the GRPW method f or each Area Sink . 5. Sim ulation The perf or mance e v aluations w ere conducted using the OMNET++ discrete e v ent sim u- lator and making use of the MiXiM fr ame w or k. The obtained results are presented and compared to GRPW protocol in ter ms of netw or k lif etime as w ell as the a v er age remaining energy and the energy consumption. The beha viour of the netw or k lif espan is also e v aluated and analysed as the netw or k scalability is increased in order to study its eff ect on the perf or mance . The idea of using f our interconnected sinks is also to allo w m uch more distr ib uted energy consumption throughout the netw or k as a mechanism to f acilitate energy balance . 5.1. Sim ulation Results 5.1.1. Number of Dead Nodes 20 40 60 80 100 120 140 160 0 10 20 30 40 50 Sim ulation Time (min) Dead Nodes GRPW GRPW -MS Figure 3. Number of Dead Nodes F rom Figure 3 , w e see that GRPW -MuS outperf or ms other protocols significantly , with GRPW -MuS close to doub ling or tr ipling the time to first sensor nod e f ailure in some cases . In GRPW , the first node dies quic k er than the other protocols , because all pac k ets are sent to only one sink and there is no m ultiple sink nodes le v els reconstr uction and path s witching. The GRPW - MuS Algor ithm decrease energy consumption which ca n impro v e the lif etime of sensor nodes and the GRPW -MuS Algor ithm uses the m ultiple sink nodes which impro v e the load-balance of data which is sent to sink nodes . Ho w e v er , GRPW -MuS b y combining m ultiple sink nodes , le v els reconstr uction and pa th s witching, can best bala nce sensor energy consumption and prolong the dur ation f or sensor netw or k which is fully functional. 5.1.2. A vera g e Ener gy Consumption In Figure 4 and Figure 5, This can be seen where the hop count and distance decreases with time f or most algor ithms . GRPW , ho w e v er , beha v es a bit diff erently in that its a v er age dis- tance to sink does not decrease m uch o v er time , meaning that it is still ab le to k eep some of the outlying sensors aliv e (and hence the higher a v er age distance). Despite the longer actual dis- tance from the sinks (which g reatly aff ects the energy consumption of the pac k et), GRPW -MuS IJEECS V ol. 4, No . 3, December 2016 : 486 498 Evaluation Warning : The document was created with Spire.PDF for Python.
IJEECS ISSN: 2302-4046 493 0 20 40 60 80 100 120 140 2 3 4 Sim ulation Time (min) A v er age Hop Counts F or P ac k et to Sink GRPW GRPW -MS Figure 4. A v er age Hop Count vs Time 0 20 40 60 80 100 120 140 1 1 : 5 2 2 : 5 3 10 3 Sim ulation Time (min) A v er age energy consumption f or one pac k et (j) GRPW GRPW -MS Figure 5. A v er age Energy Consumption f or pac k et still maintains the best a v er age energy consumption per pac k et, which is a tr ib ute to the le v el maintenance and path s witching mechanisms . 5.1.3. Saf e time Here the saf e time is denoted as a n umber of hopes the adv ersar y ha s to tr a v el to find the location of the sink. The total n umber of hopes includes a n umber of hope at the f ak e path and n umber of hopes at the real path the adv ersar y has to mo v e to locate the sink. Figure 6 sho ws saf e time as a function of a n umber of sinks . The saf e time f or GRPW -MuS and GRPW go on increasing the n umber of sink is increased. The perf or mance of GRPW -MuS is better compared to GRPW as in GRPW -MuS the node are divided into the n umber of z ones and hence m ultiple paths are gener ated sim ultan eously in the netw or k and hence saf e time is more while GRPW -MuS: Routing to Multiple Sinks in WSNs (SABRI Y assine) Evaluation Warning : The document was created with Spire.PDF for Python.
494 ISSN: 2302-4046 2 4 6 8 40 60 80 100 120 140 Number of Sinks Saf e time (Denoted b y hops) GRPW GRPW -MS Figure 6. Saf e time as a function of n umber of sinks using GRPW -MuS . 5.1.4. P ac ket Deliver y Ratio 2 4 6 8 80 90 100 Number of Sinks P ac k et Deliv er y Ratio (%) GRPW GRPW -MS Figure 7. P ac k et Deliv er y Ratio (%) as a function of n umber of sinks Figure 7 sho ws the pac k et deliv er y r atio as a function of a n umber of sinks . The pac k et deliv er y r atio in GRPW and GRPW -MuS initially decrease up to a n umber of sink 2, after which it increases with increasing n umber of sink. The pac k et deliv er y r atio f or GRPW and GRPW -MuS almost remains identical as a function of n umber of sinks . 5.1.5. A vera g e Thr oughput (kbps) Figure 8 sho ws that perf or mance of GRP W -M uS is slightly better f or the a v er age through- put as compared to GRPW . P erf or mance GRPW and GRPW -MuS are increases in a v er age throughput as a function of n umber of sinks . Due to z one par titioning done b y GRPW -MuS , It increases perf or mance f or an a v er age throughput. IJEECS V ol. 4, No . 3, December 2016 : 486 498 Evaluation Warning : The document was created with Spire.PDF for Python.
IJEECS ISSN: 2302-4046 495 2 4 6 8 4 6 8 10 12 Number of Sinks Throughput (Kbps) GRPW GRPW -MS Figure 8. A v er age Throughput (kbps) as a function of n umber of sinks 5.1.6. Normaliz ed Routing Load 2 4 6 8 2 4 6 8 10 12 Number of Sinks Nor maliz ed Routing Load (Pkt sent/recvs) GRPW GRPW -MS Figure 9. Nor maliz ed Routing Load as a function of n umber of sinks Figure 9 sho ws that perf or mance of GRPW is slightly better f or nor maliz ed routing load as compared GRPW -MuS . The routing load dr astically increases f or both GRPW and GRPW -MuS up to a n umber of sink-2 and then decreases linear ly with increasing n umber of sink. 6. CONCLUSION AND FUTURE W ORK In this paper , w e designed the ne w scheme to pro vide the Multiple Si nk location pr iv acy in WSNs . W e use the GRPW -MuS routing p rotocol based on le v el par titioning without relying on geog r aphical inf or mation about the sensors and the sinks . Using le v els par titioning, the n umbers of nodes are divided into se v er al le v els . The f ak e pac k et injection scheme is used to protect the location pr iv acy in which the real tr affic is routed through the shor test path. Moreo v er , The v ar ious f ak e paths are gener ated b y gener ating f ak e pac k ets to f ak e sinks . It is seen that GRPW - GRPW -MuS: Routing to Multiple Sinks in WSNs (SABRI Y assine) Evaluation Warning : The document was created with Spire.PDF for Python.