A Composed Energy Aware Metric for Wireless Sensor Networks
A web of detectors be composed of a batch of nodes, deployed and distributed to roll up informations from their environment. Sensor Networks functionality appears when detectors cooperate to each other, which means, each detector have a limited functionality, and they can carry through a few processing or monitoring maps but when they cooperate with the other detectors, they can make a batch of functionality in inside informations.
Like as the other webs, Sensor Networks can be deployed with radio nodes, which make the ability to remote connexion, so called Wireless Sensor Networks. Figure1.1.2. In the past old ages, Wireless Sensor Networks have been used for diverseness applications such as battleground surveillance, Forrest fire sensing, Habitat monitoring, Smart Homes and so on. For case in the smart places, the detectors make intelligent determinations as to how to accommodate, what changes to do, what actuations to be performed based on the transforming provinces of the environment. An illustration scenario could be the visible radiations turning on when a individual enters the room at dark, commanding room temperature by exchanging the cooling/heating degrees of an air conditioner etc ( Ankit Mehta, 2005 ) . 1.1.3.
One of the most of import restraints on radio detector nodes is the low power ingestion demand. Wireless detector nodes carry limited, by and large unreplaceable, power beginnings. While traditional webs aim to accomplish high quality of service ( QoS ) commissariats, detector web protocol must concentrate chiefly on power preservation. They must hold inbuilt tradeoff mechanism that give the terminal user the option of protracting the web life clip at the cost off lower throughput or higher transmittal hold ( I.F.Akyildiz, 2001 ) . There are several factors that influence the radio detector webs lifetime such as web topology, routing protocol, and detector node design in point of hardware position. All aforementioned factors have been studied and developed by many research workers but there are still challenges to happen out a hardiness radio detector web in footings of power preservation. One of the most of import of these factors is routing protocol in WSNs, which its chief end is, happening communicating waies between nodes, and taking the best way. In recent old ages, many routing protocols have proposed for WSNs, and implemented with different applications.
One illustration of a power cognizant routing protocol is the Directional Source Aware Routing Protocol ( DSAP ) . The Directional Source-Aware routing Protocol ( DSAP ) was developed by Salhieh, Weinmann, Kochhal, and Schwiebert in 2001 ( Salhieh, 2001 ) . Harmonizing to [ Salhieih [ 9 ] etal, 2001 ] , in DSAP, after completing roll uping the information from the neighbours and based on this information, the routing protocol decides which neighbour should have the package.
1.2 Problem statement
Directional Source cognizant protocol is one of the WSNs routing protocol which was developed by Salhieh, Weinmann, Kochhal, and Schwiebert on 2001 ( Salhieh, 2001 ) . This protocol is a local information routing protocol, which, each node merely knows about its neighbour ‘s information. Furthermore, each node transmits the package to a peculiar neighbour, which is closer to the finish. Then the new node is in charge of the package and, it will send on the package by one of its neighbours once more. This process will go on, until the package reaches finish. Making this determination, which node ‘s neighbour should be choice to send on the package, is based on a Directional Value ( DV ) parametric quantity.
DV is a parametric quantity that, stand for the each node ‘s geometric place in the web. Some prosodies and methods were developed for DSAP, such as power cognizant metric ( A.Salhieh, 2004 ) to protracting detector web life-time. But there is still an issue in current power cognizant metric. Current power aware-DSAP metric most of the clip takes the neighbour ‘s node which has the most power with shortest way. Taking the peculiar waies causes to consuming energy in specific nodes in web and imbalanced power dissipation in web. Therefore, some nodes in the web stay untouched, whereas they could take part as a way to protracting the web life clip and besides increasing the figure of message bringing. If this job is solved, the life-time of the detector nodes can be prolonged.
The aim of this research is to suggest a new metric to be used in the DSAP protocol which will protract the life-time of the detector nodes in the web. The metric proposed in this research could assist equilibrating the web ‘s node energy dissipation by utilizing different nodes decently as the chosen way alternatively of utilizing some nodes more often.
In this thesis, the proposed metric is applied to the DSAP routing protocol in a 2-Dimentional topology with 4-neighbors. Although the protocol can be used by nodes with more than 4-neighbours, it will non be considered for this research. Furthermore, the three-dimensional topology will non be considered every bit good. The proposed metric will be tested for a web with 12 nodes, and the beginning and finish are fixed. Harmonizing to the basic DSAP which is based on merely local information, we followed that regulation in the new metric, excessively.
The proposed metric could protract the life-time of the detector nodes used in the WSN. By protracting the life-time of the detector nodes, a batch of information could be gathered and can be used by assorted types of applications such as, military, wellness, and environment. This can lend to the wellbeing of the society.
1.6 Organization of the Dissertation
In the first chapter the overview of the research has been given. In add-on, the aim, range and important were besides given. In chapter 2, the radio detector webs engineering will be explained in item. In add-on, the routing protocols used in the WSN will besides be discussed. One of the protocols known as the DSAP will besides be discussed in this chapter. In chapter 3, the treatment will be focused on the current DSAP and the last alteration for energy consciousness for DSAP. Later in the chapter, the proposed new metric will be introduced. The proposed new metric will be explained in inside informations in chapter 4. After that, chapter 5 would be discoursing about the simulation theoretical account developed to prove the proposed metric. The consequence and treatment of the simulation will besides be discussed in this chapter. Finally, the thesis will be concluded in chapter 6, by giving the analysis of the consequences and the dissection for future plants.
In this chapter, the overview of the research has been given. In add-on, the aim, range and important were besides given. In the following chapter the radio detector webs engineering will be explained in item.
Chapter 2 Wireless Sensor Networks
Wireless Sensor Network ( WSN ) can be said to be the latest member to the informations webs household. A typical WSN would consists of a figure of detector nodes ( can even be in 1000s of them ) ( I.F.Akyildiz, 2001 ) . All the nodes has separate detection, processing, storage and communicating unit. The place of detector nodes need non be predetermined ( Ankit Mehta, 2005 ) . 2.1.1 shows an illustration of a detector node. There are more than one type of detector nodes that could be used. The size of the detector nodes can be every bit little as the size of a grain or every bit large as the size of a typical shoebox.
The detector nodes are used to roll up informations depending on the type of applications they are used for. The nodes can be used to roll up informations for military intents, such as battleground surveillance, or it can be used to roll up informations for supervising the environment, such as for roll uping temperature, or it could be used to roll up informations for wellness monitoring intents, such as for supervising bosom round.
After the nodes have collected and processed the information, they will convey the needed information to the computing machine ( besides known as the base Stationss ) that collects the information ( I.F.Akyildiz, 2001 ) . The information is propagated to the base station via a wireless transceiver or other wireless communications device utilizing a pre-defined routing protocol.
There was an issue of compatibility of transducers for different web before the Institute of Electrical and Electronic Engineer ( IEEE ) developed a criterion for WSN. As a consequence, in 1993, the IEEE together with the National Institute of Standards and Technology ( NIST ) started the enterprise to plan a criterion for smart detector webs. The general theoretical account for the Smart Sensor Networks is shown in 2.1.2. By holding this criterion, it is more easy for makers to develop smart detectors and to interface those devices to webs ( Lewis, 2004 ) . An illustration of WSN design is given in ( Ankit Mehta, 2005 ) . Mehta ( Ankit Mehta, 2005 ) used a middleware as shown in 2.1.3 in planing his WSN.
Each of the detector nodes depends on an energy beginning, usually a battery, to provide the power in order for it to be able to work. Today, one of the biggest issues that the research communities all over the universe attempt to work out is to protract the life-time of the detector nodes. In order to accomplish this aim, there have been many proposals such as utilizing the hardware involved in the WSN, utilizing directional aerials and one of the recent enterprises is to utilize power-aware routing protocols to be used by the WSN ( Lewis, 2004 ) .
2.2 Routing Protocols in WSNs
Before the types of routing protocol in radio detector webs are discussed, some challenges in radio detector webs will be considered in contrast with other traditional webs such as nomadic ad hoc webs or cellular webs, as discussed in ( Jamal N. AL-Karak, 2004 ) .
The first challenge faced by the radio detector web is, the infeasibility of holding a planetary addressing strategy. Due to the comparatively big figure of detector nodes, it is non possible to construct a planetary addressing strategy for the deployment of a big figure of detector nodes as the operating expense of ID care is high. Therefore, traditional IP-based protocols may non be applied to WSNs.
The 2nd challenge is, in most applications of detector webs, demand is flow of perceived informations to a peculiar base station in contrast to typical communicating webs. However, physically detectors can non forestall the other signifiers such as multicast or equal to peer. For case, an application of detector web which is supposed to gathered informations and direct to a BS. It does non necessitate broadcast the sensed informations to whole web. Therefore, it is considerable point that most be concerned to plan of a protocol for detector webs to forestall other signifiers of communicating every bit much as they can. ? ? ? Necessitate more information here!
The 3rd challenge is, energy, processing, and storage capacities are really critical consideration in detector nodes. Therefore, a suited resource direction mechanism is enormously required. The aim now is to protract the life-time of detector nodes so that more information can be gathered.
The 4th challenge is, web topology. Almost the nodes in all application scenarios in WSNs are by and large stationary after deployment except for possibly a few nomadic nodes in contrast with traditional radio webs that they are free to travel. Therefore, the routing protocol demands to plan decently for this sort of low mobility topologies. ? ? ? Necessitate more information here!
The 5th challenge is, assortment of application of detector webs with specific belongingss and demands ( i.e. , design demands of a detector web alteration with application ) . For case, the disputing job of low-latency preciseness tactical surveillance is different from that of a periodic conditions monitoring undertaking. In other words, planing routing protocols for detector webs are really application demanded because of this diverseness. ? ? ? Necessitate more information here!
The 6th challenge is, informations collected by many detectors in WSNs is typically based on common phenomena, so there is a high chance that this information has some redundancy. ? ? ? Necessitate more information here!
Based on the challenges faced by the detector webs, many research workers have studied, and presented assortment of routing protocols, which are suited to be implemented with radio detector webs as mentioned in ( Jamal N. AL-Karak, 2004 ) . All these routing protocols, have either dealt with one or more challenges mentioned in the old paragraphs.
By and large, routing protocols in WSNs can be classified into two chief classs with regard to its web construction or the protocol operation. In the Network construction class, there are three subcategories, viz. : level, hierarchal, and location based. In the protocol operation class, the WSNs routing protocols can be categorized in five subcategories, viz. , Negotiation-based routing, Multipath-based routing, Query-based routing, QoS-based routing, and Coherent based routing. 2.2.1. ? ? shows the categorization of routing protocols in WSNs based on these two classs.
Furthermore, the routing protocols can be classified into another three classs, depending on the path finding, i.e. : Proactive routing protocols, Reactive routing protocols, and Hybrid routing protocols ( Ilikhan, 2008 ) . 2.2.2. ? ? shows the categorization of routing protocols in WSNs based on its path finding.
In level webs, all nodes are in the same degree and play the same function. The feeling undertaking is performed with the coaction of all nodes. Typically, a level routing uses base BS ( s ) to direct questions to certain part, and delaies for the answer from the node ( s ) within that part. In this web, the routing protocols would happen the waies by utilizing the multi-hop question dissipation from the beginning to the finish, or from finish to the beginning. An illustration of a routing protocol based on this web is Sensor Protocols for Information via Negotiation ( SPIN ) .
Heinzelman et Al. in ( Kulik, Heinzelman, & A ; Balakrishnan, 2002 ) has proposed a household of adaptative protocols called Sensor Protocols for Information via Negotiation ( SPIN ) that is based on dialogue between nodes in the web. In this protocol, each node will portion its information with the other nodes. The dialogue is handled by the meta-data by taking for each node in order for it to cognize about available resources and informations from its neighbours. The dialogue besides will guarantee that the node will merely convey the information when it is necessary and to guarantee that it will ne’er lose the energy unless through transmittals.
The SPIN operates with three sort of messages ; ADV, REQ, and DATA. The ADV will be broadcasted by a node which holds the new informations. After that, the neighbours, who are interested about that information, will response to the message by directing REQ message to the beginning node. After the petition message has been received, the beginning node will direct the DATA message to the interested node. This process is shown in 126.96.36.199.1.
As shown in 188.8.131.52.1, node A starts the process by publicizing informations to node B ( a ) . Node B responses by directing a petition to node A ( B ) . After the having the requested information ( degree Celsius ) , so node B sends out advertizements to its neighbours ( vitamin D ) , who in bend send requests back to B ( e-f ) .
Scalability is one of the challenges in radio detector webs. A hierarchal architecture for radio detector webs is one perfect solution to turn to this scalability issue and besides in increasing the web life clip. In hierarchal routing, nodes with higher energy will be used to treat and convey information while other nodes with low energy are used for feeling. Hierarchical routing is called cluster-based, because the nodes are clustered together and has a bunch caput ( CH ) which is assigned a particular undertaking. CHs in each bunch of web sum sensed informations from detector nodes and transmit these informations to BS instead than for each detector node to direct perceived informations straight to the BS. The CHs usually are non inactive ; they change often depending on their staying energy. Hierarchical routing is an efficient routing to increase the scalability, web life-time, and energy efficiency. Low Energy Adaptive Clustering Hierarchy ( leach ) is an illustration of routing protocol under this class.
Low Energy Adaptive Clustering Hierarchy, so called LEACH, was developed by Heinzelman, et. Al ( Akayya & A ; Younis, 2003 ) in 2000. LEACH is a self-organized, hierarchal routing protocol, which selects a few nodes as bunch caputs ( CHs ) indiscriminately in webs. This random election causes to help load-balancing in the web. Compressing informations by the CHs is an advantage in LEACH to cut down the sum of information that must be sent to the base station. In other word, nodes in each bunch, sends the information to CH and so CH compresses the information to aggregated packages, and direct it to the base station. By making so, a bundle of informations be sent to establish station instead than directing informations often from CH to establish station. Furthermore, the informations aggregation is centralized in LEACH and is performed sporadically. However, the function of CHs rotates indiscriminately for more efficient energy dissipation in web.
2.2.3 Location based
In location based routing, detectors are declared by their locations. That means each node is addressed by its location. By making so, some computation such as appraisal of distance between nodes or calculation of cost of way, becomes much easy. Location turn toing in nodes depends on the type of web and protocols, for case, in some routing protocols, the node ‘s location information addressed by a low-power GPS receiving system ( Rodoplu, 1999 ) , and some protocols addressed fix location information to their detector nodes during the web low-level formatting. Furthermore, the most location based routing protocols are designed for nomadic ad hoc webs but this sort of routing can be used for stationary webs every bit good ( SALHIEH, 2004 ) ( Nath & A ; D.Niculescu, 2002 ) . However, some of these protocols such as ( Nath & A ; D.Niculescu, 2002 ) were non suited for radio detector webs, because they are non concerned about energy ingestion.
Since the detector nodes knew about their locations in location based protocols, hence, we can do the web to some portion geographic parts. Geographic and Energy Aware Routing ( GEAR ) was developed by Yu et Al. in 2001 ( Yu, Govindan, & A ; Estrin, 2001 ) . GEAR uses the geographic information to circulating questions to proper parts. GEAR ‘s basic thought derived from directed diffusion by directing involvements to a certain part alternatively of directing the involvements to whole web. This means, decrease the figure of involvements, therefore, more energy preservation than directed diffusion.
There are two sort of costs in GEAR ; estimated cost and larning cost. Each node computes a combination of residuary energy and distance to finish as estimated cost. In some juncture there are holes in the web when a node does non hold any closer neighbour to the mark than itself. Then, the erudite cost re-estimates from estimated cost to manage these holes. The estimated cost and learned cost are equal when there are no holes.
Routing algorithm in GEAR consists of two stages: Forwarding packages towards the mark part: in this stage, when a closer neighbour to the finish exists, the next-hop node which is closer to destination will be picked up. If the all neighbours are farther off, which means there is hole, so, the learned cost will be used to pick next-hop node instead utilizing the estimated cost. Circulating the package with in the part: When the package has reached the part, it can be disseminated in that part. There two ways for that airing ; recursive geographic forwarding and restricted implosion therapy. The restricted part is used when the detectors are non dumbly deployed, but in instance of high-density webs, recursive geographic implosion therapy will be used. The recursive implosion therapy divides the part into four bomber parts and four transcripts of the package ( 184.108.40.206.1, illustrates the splitting parts ) , so this undertaking continues until the parts with merely one node left.
2.2.4 Power consciousness routing protocols
220.127.116.11 Energy-aware routing protocol ( EAR )
As we mentioned in routing protocols in WSNs subdivision, one of the most challenges in routing protocols is the energy ingestion. Shah et Al. in 2001 ( Shah & A ; Rabaey, 2001 ) developed a new routing protocol, called Energy Aware Routing ( EAR ) . The Ear is really similar to directed diffusion ( Intanagonwiwat, Govindan, & A ; Estrin, 2000 ) in some parts, but they are wholly different in way choice. The EAR finds multipath between sink and beginning, and chooses the many waies based on a probabilistic manner. In the other manus, directed diffusion selects a individual optimum way for communicating. The chief thought for Energy Aware Routing protocol was to forestall the web to be partitioned by taking multipath, instead than utilizing one individual way and depleted some nodes and partitioned the web.
There are three stages in the Ear: apparatus stage, informations communicating stage or informations extension stage, and route care stage. In the apparatus stage, the mobs will be discovered by deluging the involvement to the web and happen all possible paths between beginning and finish. In add-on, the routing tabular arraies build in the apparatus stage and all the paths cost will be calculated and inserted to the routing tabular array. In this stage all the cost of paths calculate and compose on the routing tabular array:
( 18.104.22.168.1 )
, is the cost between node and node. The Metric is an energy metric, that calculates the metric cost by communicating energy and residuary energy of each nodes i and J. Furthermore, the waies with high cost will be discarded, merely the way with low cost will add to the routing tabular array. Then will delegate a chance reciprocally relative to the cost, for each of the neighbours in the forwarding routing tabular array ( FT ) :
( 22.214.171.124.2 )
The cost of node with norm of the chance of choosing neighbours in the forwarding tabular array and cost of neighbours, calculates by this expression in below:
( 126.96.36.199.3 )
The information communicating or extension stage will direct the package through the web from beginning to the finish by taking the neighbours who has the same chance with the chance in the forwarding tabular array, until the package reaches to the finish.
The 3rd stage, which is care stage, runs a localised implosion therapy to updates the all waies.
188.8.131.52 Decentralized power cognizant routing protocol
In radio detector webs, communicating has more energy ingestion alternatively of the other operations such as processing, harmonizing to the research in ( Pottie & A ; Kaiser, 2000 ) . This high cost of communicating was encouraged to do decentralised protocols for WSNs. The decentralized protocols portion treating undertakings to each node in the web instead than centralisation processing. This means each node can treat and calculate their local available information. Decentralization aims to cut down the figure of control messages, which need to be sent in the web to detect paths. However centralised protocols have advantages to happen the optimal waies because they gather planetary information, but in point of energy ingestion, the decentalisation because of decrease of figure of control messages might be a good solution. In ( Salhieh, 2001 ) ( Salieh, Weinmann, Kochhal and Schwiebert ) developed a decentralized routing protocol for stationary topologies to protracting web life-time. The routing protocol was wholly based on local information that is available to each node from its neighbours. Furthermore, base on the local information each node capable to do determination to send on messages to concluding finish. In this local based information protocol, consideration was on the lone local point of position in the routing protocol, therefore, there was limited information that each node can acquire from its neighbours ( SALHIEH, 2004 ) . All information is as follows:
* Cost of communicating and distance between a beginning and its neighbours.
* Cost of communicating and distance between a node and the base station.
* Number of neighbours.
* Power staying at the neighbours.
Harmonizing to these limited local information, current routing algorithms was non proper. Therefore, in ( Salhieh, 2001 ) developed a new routing algorithm, which so called directional source-aware routing protocol ( DSAP ) .
DSAP was a directional routing protocol which means, each node needs to cognize about the way of finish to send on a package to finish. 184.108.40.206.1. We will discourse more about DSAP and its prosodies in following chapter 4.
In this chapter radio detector webs is discussed and besides routing protocols in WSNs reviewed in some facets particularly about power consciousness. The DSAP protocol is introduced and in the following chapter the DSAP will be discussed in inside informations.
Chapter 3 Directional Source cognizant routing protocol ( DSAP )
Harmonizing to categorising the routing protocols based on path finding, there are three sort of routing protocols which are proactive, reactive, and intercrossed. Proactive routing maintains paths to every other node in the web, therefore a path can be provided instantly when requested. Regular routing updates impose big operating expense, therefore proactive is suited for high traffic webs. Reactive routing maintains routes to merely those nodes that are needed, in other words on-demand. Each host computes paths for a specific finish merely when necessary. Therefore, the cost of happening paths is expensive, since implosion therapy is involved. This sort of protocol is good for low/medium traffic webs. Traditional reactive protocols find the best path and so ever use that path, but that is non the best solution for a radio detector web. This sort of routing is non an efficient manner of routing, since we want the protocol to be power cognizant and beginning aware. The 3rd class maintains partial topology information of local hosts. Routing determinations are made either proactively or reactively ( SALHIEH, 2004 ) . Hence, sing to issues in these three sort of protocols and besides to happening out a suited routing protocol for decentralizing, which we have discussed in old chapter, a new routing protocol proposed in ( Salhieh, 2001 ) , so called directional beginning cognizant routing protocol ( DSAP ) .
As mentioned earlier, DSAP is a directional routing protocol, which means each nodes need to cognize way of finish to send on the package in that way. Since the DSAP is based on merely local information and nodes need to cognize about their waies, therefore, each node needs to cognize about its location in the web and other node ‘s location. For accomplishing to this end, Directional Value ( DV ) system is defined to place each node ‘s location in the web.
Directional value is a alone designation value that uses to place location of each node in the web. There are some belongingss for DV as follows ( SALHIEH, 2004 ) :
* Each node has a alone ID.
* Each ID gives how far the node is from the web margin in each way.
* Each node can calculate the comparative way of another node from its ID.
In order to building the directional value, each node needs has fixed figure of neighbours, the figure of neighbours are depend on the topology that is used in the web. For case, a web with 2D-4 topology, which means 2 dimensional with 4 neighbours, each node has 4 neighbours that they are stand foring waies that the node can route through them. 3.1 illustrates some types of 2D topologies in directional routing.
The directional value of each node is how far a node is from the border of the web in each way. The DV for each node is alone and can be used as an ID figure which is necessary to utilize for routing. 3.2 shows a 4 Neighbor topology, which node-s has 4 borders D-0, D-1, D-2 and D-3 to 4 neighbours, severally to neighbor-0, neighbor-1, neighbor-2, and neighbor-3. Therefore, the ID of node-s would hold an identifier of ( ) . This means that there are nodes to the border in way D-0, in D-1, in D-2, in D-3.
In 3.3 a sample of web T-4N with 11 is showed, for illustration in this, node ( 1, 1 ) would hold an identifier of ( 1, 1, 2, 1 ) . This means there is 1 node to the border in way 0 ( left ) , 1 node in way 1 ( up ) , 2 nodes in way 2 ( right ) , and 1 node in way 3 ( down ) .
Since each node knows about their location and besides about their neighbours ‘ location by directional values, the DSAP algorithm ( Salhieh, 2001 ) ( 3.4 ) is ready to get down to route messages from beginning to finish. The basic strategy of DSAP algorithm is, finish node identifier subtracts from beginning node identifier. This subtracting will come out a new DV, so the negative waies in this new DV will be eliminated and the positive directional Numberss would be used as possible of path to send oning the message. The beginning ‘s neighbours with positive directional figure will be deducting once more from the finish node identifier. The same as the beginning node, the subtracting comes out a new DV for the each neighbour, so all the directional Numberss in new DV for neighbours will be add together and the neighbour with little value will be choose as the following hop. Furthermore, if some nodes have the same DV, so one of them will be choose indiscriminately. The chosen neighbour node assumes as the beginning, and this procedure repeats until amount of directional Numberss in new DV being 0, which means the message reached the finish.
For case, if we consider the node ( 1,1 ) in, as the beginning, and node ( 2,3 ) as the finish. The followers is the process that a message will convey from the beginning to the finish:
First of all, beginning node ( 1,1 ) with ( 1,1,2,1 ) subtracts from the finish node ( 2,3 ) with ( 3,2,0,0 ) . So, beginning – finish = ( -2, -1,2,1 ) . The nonnegative directional Numberss consider as possible paths, which are node ( 1,2 ) in way 2 ( right ) and node ( 2,1 ) in way 3 ( down ) .
Second, the directional value of each possible node for routing will deduct from finish DV. In this instance, ( 2,1,1,1 ) – ( 3,2,0,0 ) = ( -1, -1,1,1 ) , so the new DV directional Numberss add to garner, which makes the value of 4. The same procedure performs for node ( 2,1 ) , ( 1,2,2,0 ) – ( 3,2,0,0 ) = ( -2,0,2,0 ) , after adding the directional Numberss, the DV for this node is 4. The following measure is comparing between two DVs value which are precisely the same in this instance with value of 4. Therefore, the algorithm chooses one of these nodes as following hope, and will send on the message to it. If we assume that the node ( 2,1 ) has been chosen, this node will considered as beginning in the algorithm and the same procedure will be perform until the DV of 0.
The basic strategy of the DSAP is non an efficient power cognizant routing because the paths are chosen without power consideration. Therefore, in ( Salhieh, 2001 ) the writers, developed a new metric for DSAP, which was a power cognizant metric. This metric will be introduced on the following subdivision.
3.1 Power cognizant DSAP
In position of the fact that the power ingestion is highly of import in wireless routing protocols, hence, taking attention of available energies on each node in web must be considered in directional beginning cognizant routing protocol excessively. For making to this end, several power prosodies were developed by Salieh and Schweibert in 2004 ( A.Salhieh, 2004 ) . The prosodies all are based on the basic strategy of the DSAP algorithm and besides they are utilizing the local information available in the web, which has been mentioned in chapter 2, consequently, each node knows about its neighbour ‘s residuary energy. Besides, since DVs of each neighbour is estimable by beginning nodes so ciphering the figure of hops is possible.
Developed prosodies are included of power merely, Directional Value merely, DV and power, the amount of power and directional value, figure of hops, the cost of path and figure of hops, and combination of all them.
3.1.1 Power Merely
In this metric, DSAP calculates the DV of beginning node to find the positive waies and so send on the package to the neighbour with maximal power available. The issue is, the metric may take longer waies because of power, hence, doing energy more depletion in the web.
3.1.2 Directional Value Merely
The Directional Value Only considers merely the DV of its neighbours with regard to the concluding finish, which is precisely the basic strategy of DSAP algorithm. Since this metric does non care about the energy available in the neighbour nodes and merely makes determination for send oning the package based on merely DV, hence it may takes waies with short length but really dearly-won. Therefore, it is non a power efficient metric.
3.1.3 DV and Power
The combination of two prosodies, Directional Value and Power is another metric that was developed by Salieh and Schweibert ( A.Salhieh, 2004 ) . It is energy efficient metric that considered the upper limit available power and minimal DV when picking which node route to take. Rather than picking the node with last DV or maximal power, the DV divided by the power available at that node. The smallest value of this power-constrained DV is the way that is chosen. The inside informations of algorithm shown in 3.1.3.
One issue in this metric is, in some instances the metric choose the longer way because of the available power dictates. Therefore, it may do imbalanced energy dissipation in the web.
3.1.4 DV and Sum of Power
This metric is about the same as the DV and Power is, but alternatively of looking at the power at the neighbours of the beginning, it looks one hop beyond these neighbours from each neighbour. By making so the protocol may hold a better pick in picking the following path.
3.1.5 Number of Hops Merely
Harmonizing to bing information from DV, the figure of hops can be calculated. The figure of hops gives a maximal and minimal figure of hops for each way. This metric uses the norm of those two Numberss to do a pick on routing the package. The neighbour with minimal figure of hops will be chosen to be frontward the package.
3.1.6 Hops and Cost
This metric, uses the figure of hops and from figure of hops, the cost of routing in each way can be calculated. The process starts by picking up the first hop and multiply by the figure of neighbours, it is because of when a node transmits a package to another node, all neighbours of the beginning node will have the package, which means cost of that path. The metric utilizing the norm of the figure of hops and cost to taking the following node that the package must be forwarded.
3.1.7 Hops, Cost, DV, and Sum of Power
In this metric which obliviously is a combination of all prosodies. In another words this metric utilizations of all available information in the web. First of wholly, the value of the figure of hops and cost estimation so the DV and amount of power at the neighbour will be calculated. Last, the node with minimal value of ratio between those two values will be chosen the package to be forwarded.
Harmonizing to simulation consequences of research in ( A.Salhieh, 2004 ) , for all prosodies have mentioned. The DV and Power and DV and amount of power are the most efficient metric to protracting the life-time of nodes in the web. These prosodies extend the web lifetime about % 29 and % 31, severally instead the basic strategy of DSAP which is metric with DV merely.
3.2 Modified DSAP
Recently Samir, Marc and Bachar developed modified DSAP ( MDSAP ) in ( El-Haddad, Girod-Genet, & A ; Hassan, 2007 ) . They addressed to the issue of current DSAP restrictions, which was taking way with maximal power even it is non the shortest way in some instance. Furthermore, they addressed to taking the different way alternatively of utilizing one way ever. MDSAP basic thought was to categorise the message in the web to three classs which were included: high precedence, medium precedence, and low precedence.
High precedence messages in MDSAP protocol are forwarded to following node with highest power. In high precedence message instance, making to finish is the end and the protocol does non care about way long. Therefore, the message routes with longest way but with most energy.
MDSAP chooses the shortest way every bit long as the power is over a certain threshold, when the message is a medium precedence message. But when the power is blew the threshold the way will alter to 2nd shortest way that power of nodes are over the certain threshold. There is an exigency instance in this state of affairs when all neighbour nodes are below the threshold. In this instance, the message will be changed to pressing message and the way with maximal power will be chosen.
Low precedence messages instead than high precedence messages ever takes the shortest way, no affair what is the power of the nodes.
MDSAP for attack to acquire its neighbour power information, the neighbour sends three types of warning message. These messages are the undermentioned ( El-Haddad, Girod-Genet, & A ; Hassan, 2007 ) :
* A debug message labeled “Node OUT of power” is sent when the power of the node is equal to zero.
* A message labeled “NODE is half-power” is sent when the staying power degree reaches 50 % .
* A message labeled “Message is lost at this Node” will be displayed when all the neighbours of a given node run out of power.
Harmonizing to simulation consequences in ( El-Haddad, Girod Genet, El-Hassan, & A ; El-Nabbouch, 2008 ) , MDSAP in contrast with regular DSAP, improved the web life-time, and more public presentation in making a message to concluding finish. The consequences shows ( table 3.2.1 ) when MDSAP utilizing merely high precedence the web life clip 22 % additions, the prolonging of web life-time for medium precedence, low precedence, and random precedence are 55 % , 77 % , and 88 % severally.
Compared with the regular DSAP
Random ( 1,2,3 )
Table 3.2.1: MDSAP comparing consequences with Regular DSAP
Beginning: ( El-Haddad, Girod Genet, El-Hassan, & A ; El-Nabbouch, 2008 )
However the modified-DSAP increasing the web life-time in contrast with regular DSAP but it needs categorised messages in web, hence this algorithm may non be efficient if an application needs has a web with a fix sort of message. In other words, MDSAP is an application demand protocol.
3.3 Proposed power cognizant DSAP metric
In this thesis, we presented a combined metric includes of current power aware-DSAP metric and a new metric. The thought is, when a node has been used one clip before in way, it will take a new metric alternatively of utilizing the current power aware-DSAP metric. Otherwise, it takes the power aware-DSAP metric and finds the node to route. When the new metric be chosen, the neighbour node will state a prevarication about its staying energy to its parent beginning node, so the new metric evaluate by this untrue energy value. It could diminish the opportunity of taking that node, which has been taken one clip before. This new metric would name white-lie, because of the prevarication can assist the web to be survive for more clip. Hence, the web life clip will be addition, and besides other nodes will be use decently in way to increase the opportunity of message bringing. The proposed metric will be explained in item in chapter 4.
In this chapter, the Directional Source-Aware Routing Protocol ( DSAP ) discussed in item. Power consciousness prosodies for DSAP mentioned and harmonizing to the simulation consequence in ( A.Salhieh, 2004 ) , the DV and Power metric was the best metric for protracting life web life-time. Subsequently on, Modified DSAP is given, which was a new algorithm for DSAP to widening web life-time. Finally, the new proposed metric discussed to protracting web life-time and increasing the figure of message bringing in DSAP protocol.
Chapter 4 Proposed power cognizant DSAP metric
After analyzing the all current prosodies and algorithm in DSAP, restrictions such as imbalanced power dissipation in Power-DSAP and application demand in MDSAP, the clip is to suggest the new metric power aware for DSAP protocol. The basic thought is when a node has been used one clip before in a way. It will take a new metric alternatively of utilizing the current power aware-DSAP metric. Otherwise, it takes the power aware-DSAP metric and finds the node to route. When the new metric be chosen, the neighbour node will state a prevarication about its staying energy to its parent beginning node, so the new metric evaluate by this untrue energy value. It could diminish the opportunity of taking that node, which has been taken one clip before. This new metric would name white-lie, because of the prevarication can assist the web to be survive for more clip. Hence, the web life clip will be addition, and besides other nodes will be usage in way to increase the opportunity of message bringing. This new proposed metric avoid to airing control messages or categorising messages in the web instead than the MDSAP.
This proposed metric for DSAP, is to find the directional value for each neighbour nodes which are supposed to be chosen in the following hop. Hence, if the neighbour node has been chosen one clip before, therefore the directional value for that node will be evaluate with proposed new metric, otherwise, the metric DV and Power will be chosen to cipher the directional value. Then eventually as the DSAP protocol routine the directional values for all positive way neighbours of beginning will be compared to be choice the 1 with minimal directional value. Of class in instance if DVs were equal, so one node will be chosen indiscriminately.
4.2 The proposed metric algorithm
In the proposed metric algorithm as shown in 4.2.1, the neighbour node presents their residuary energy less by spliting its power with an ? value, if the neighbour has chosen one clip before. By making so, if the DV value of the neighbour with untrue power was less than the other neighbour ( s ) , so the node with untrue power will be chosen. Then the White-lie flag which is a counter to number the figure of choice a node will be changed to 0.
The White-lie flag alterations to 1 after the beginning node selected the neighbour node for the following hop. Furthermore, the White-lie flag is implemented for each node to number its neighbor figure of choice. Therefore it is wholly based on local information without airing control messages. Because each node knows that last clip which neighbour was chosen based on its White-lie flag.
For case, see a web 2D-4 with 12 nodes ( 4.2.2 ) . The web wants to send on a package from beginning node 4 to destination node 7. The proposed metric DSAP protocol starts with as regular process in DSAP basic strategy which is to measure directional value for all beginning neighbours.
In this instance, ( 0,1,3,1 ) – ( 3,1,0,1 ) = ( -3,0,3,0 ) , hence, positive waies are possible neighbours to send on the package. Node 0 in way 1 ( UP ) , node 5 in way 2 ( Right ) , and node 8 in way 3 ( Down ) are the possible neighbour nodes to send on, hence, DV of these nodes will be subtracted from DV of finish to measure each node directional value. For illustration, ( 0,0,3,2 ) – ( 3,1,0,1 ) = ( -3, -1,3,1 ) = 4, the other neighbours will be subtracted every bit good, value 2 and 4 for node 5 and 8 severally. In following measure, the DV values should be divided by their nodes residuary energy as regular DV and Power metric, but the difference is here between new proposed metric and current metric, because, in proposed metric the neighbour node will be checked if it has been chosen before so DV value will be divided to an untrue energy alternatively of its existent energy. In this instance, if we assume node 5 has been chosen before which means the White-lie flag = 1, so the proposed metric will cipher the concluding value for this node. Final value for node 5 = 2 / ( node 5 residuary energy / ?= 1.5 ) , if the residuary energy of node 5 was at a certain degree that its concluding value was greater than the other neighbour node ‘s concluding values, so the node 5 will non be chosen for this unit of ammunition. If the DSAP protocol acts as the regular power metric, the figure of taking of node 5 will be more than the proposed metric, hence, this node will be energy low Oklahoman. But, proposed metric prevents to take node 5 before its energy at a certain degree, through showing its residuary energy with untrue value. The node 5 is merely an illustration, so this process can be done for other nodes as good.
The parametric quantity ? is a value to happen the degree of residuary energy at node, nevertheless, the value ? =1.5 is non the best value and needs to analyze more to happen out an optimal expression to measure the best value for ? .
After ciphering the concluding value for node 5, the White-lie flag will be changed to 0 for node 5, because the following loop, the node 5 has non been chosen hence, must take part as a normal node with regular power metric. This process will be performed for other neighbour nodes as good.
In this chapter, the new proposed power cognizant DSAP metric is discussed in item. The basic thought of the proposed metric and the complete algorithm is explained. Two new parametric quantities defined in new proposed metric consists of White-lie flag and Alpha which are wholly new in DSAP algorithm, sing to implement the new proposed metric for DSAP. The following chapter the new proposed power cognizant metric will be simulated.
Chapter 5 Simulation theoretical account
Network simulator is a package plan that can imitate computing machine webs with their all behaviours and belongingss, and bring forthing consequences for analysis of the fake webs behaviours. This sort of package can pattern webs with devices, traffics, or even environmental phenomenal that can be impact a web in a existent universe.
A assorted web simulator platforms are developed in recent old ages to pattern and imitate WSNs, such a TOSSIM, which is a portion of TinyOS, SWAN which can be used for wireless webs or detector webs. Simulators like ns-2have besides been developed for multi-network simulation, wire or wireless.OMNET++ is, another web simulator package that has some utile detector simulator models like Castalia and Mobility model.
In this research undertaking, harmonizing to demands that need to implement a letter paper radio detector web for running DSAP protocol and besides the new proposed metric, C++ could be an suited option to make simulation. A brief debut about C++ programming linguistic communication and the grounds that C++ is chosen for this undertaking, are discussed in following subdivision.
5.1 C++ Network simulation
C++ is a middle-ware scheduling linguistic communication that was extended from C by Bjarne Stroustrup in the early 1980s at Bell Laboratories. C++ provides capablenesss for Object-oriented scheduling. However, C++ can supply both C-like manner and Object-oriented manner ( Deitel ) .
C++ widely used as a scheduling linguistic communication in package industry in different application such as application package, device driver, picture game, and etc. These application assortments show ability and powerfulness of C++ . In web simulation package country, C++ was used many times in different web simulators such as NS-2, OMNET++ as the chief scheduling linguistic communication.
In this thesis as mentioned before the C++ is used as a linguistic communication programming to imitate a radio detector web with DSAP protocol and the new proposed metric. In other words, a plan is created by C++ to imitate the web alternatively of utilizing traditional web simulators. The grounds that C++ is chosen as a tools for the simulation are as follows:
* Simplicity in execution.
* The web strategy that should be simulated was non in big graduated table.
* The bed that simulation should be focused was in physical bed. Therefore it could be handled by a low graduated table plan alternatively of utilizing complicated transition which used in other simulators.
* Graphical interfaces were non necessary.
* Results and analytical informations can be gathered as text files and manage by MS Excel for exposing as graphs.
* Easy to debug because of simpleness.
5.2 Simulation premise
Harmonizing to the web that should be simulated, there are some premises and parametric quantities to specify. Some premises are defined to do simulation simple for execution. They are listed below:
· The web simulates without any Base station node, which means the packages route internally between a beginning node to a finish node.
· Nodes in web know about their location and their neighbours location.
· Each node knows about available energy of its neighbours.
· The energy consumes by treating does non considered. Lone communicating including transmittal and having cost considered.
· Source nodes do non have the package that they are forwarded to their neighbours when the neighbours want to send on to following hop.
5.2.1 Radio Model and initial energy
A simple wireless theoretical account is assumed that is defined by Heinzelman, Chandrakasan, and Balakrishnan in 2000 ( 220.127.116.11, and table 18.104.22.168 ) ( Kulik, Heinzelman, & A ; Balakrishnan, 2002 ) . Besides, it has been used in ( SALHIEH, 2004 ) for simulation of DSAP protocol. In this wireless theoretical account, the wireless dissipates to run the sender or receiver circuitry and for the transmit amplifier to accomplish an acceptable ( SALHIEH, 2004 ) . The package size in this simulation is k= 512 spot for all packages. is the sum of energy that node demands to pass to convey a k-bit message to a distance vitamin D metres. The distance between each node in this web is d=15 m. The will evaluated from the expression in the below:
In the other side, to have the k-bit message, will be evaluated from this expression:
The initial energy for each node is considered by 0.1 J. All nodes assumed to utilize this limited sum of energy and there is no external power beginning for the web.
5.2.2 Network and Nodes
The web that is simulated in this research is a stationary radio detector web included 12 nodes in 2D-4 nodes topology. The beginning and finish are fixed which are Node 4 as beginning and Node 7 as finish ( 22.214.171.124 ) . The distance between beginning and its neighbours is d=15 m.
5.3 Network Simulation Implementation
In this portion the simulation execution is discussed in item with some portion of the beginning codification. First of wholly, the flow chart of this simulation is drawn in 5.3.1 in below. The shown, the procedure of how does the web simulation act, exactly?
Harmonizing to the flow chart, the simulation set some parametric quantities when the plan starts. These parametric quantities are such as the initial energy, location of nodes in the web, node identifier for each node, and so on. Furthermore, the web in this plan is defined as a 2 dimensional array with 3 rows and 4 columns which each cell of this matrix represents a node in the web. For case, the Net [ 1 ] [ 3 ] is the node 7. In add-on, the node identifier of each node of web besides is defined as 2D array ( 5.3.2 ) .
The energy and white-lie flag are initialized for the web by array. 5.3.3 the white-lie flag is an array with 12 cells, which each cell demonstrate the value of white-lie flag for each node, this array set by nothing because when the simulation starts, the white-lie flag for first unit of ammunition is zero.
After all definition of parametric quantities and variables in the simulation plan, the simulation starts with a infinite cringle, which is an “while ( true ) ” bid in this beginning codification ( 5.3.4 ) .
The following measure when the simulation is running is to acquire the value of minus between beginning node identifier and finish node identifier. This advancement is performed by the codifications that are shown in 5.3.5.
5.3.5: the minus between beginning node identifier and finish node identifier.
DV_node [ ] is an array to hive away the neighbour nodes directional values, hence node identifier of the positive neighbours of beginning will be subtracted by node identifier of finish node to calculate the directional value for each neighbour node. In 5.3.6 codifications is shown the inside informations of procedure of this process.
After ciphering the DVs for all positive neighbour nodes so the simulation will be performed the metric portion for doing the concluding determination which is taking the following hop and transmittal message to the following hop. This portion of simulation is the lone portion that makes the simulation of the regular DSAP metric, regular power cognizant DSAP metric, and the proposed power cognizant DSAP metric, difference.
5.3.1 node power rating and message transmittal
In this simulation plan, the energy will be evaluated when a message transmit or receive by deducting the ETx ( for message transmission ) and ERx ( for message having ) from the entire sum of energy in each node. In fact in this simulation, there is no existent message. But deducting the ETx from the available sum of energy in the node is considered the node transmitted a message to another node ( 126.96.36.199. ) , and besides, deducting the ERx from the available sum of energy in the node is considered the node received a message ( 188.8.131.52. ) . As mentioned in subdivision 5.2.1, the ETx and ERx are included the size of a message ( or package size K ) . 184.108.40.206. shown the low-level formatting of the ETx and the ERx in the beginning codification.
5.3.2 Regular DSAP Metric
In this metric as mentioned earlier in chapter 3, the following hop will be chosen merely base on the DV. Therefore since the DV calculated and stored in DV_nodes [ ] array, the simulation can compare these Numberss in this array, and selects the minimal value as the following hop. 220.127.116.11.
5.3.3 Regular Power aware DSAP Metric
In regular power cognizant DSAP metric, the DV will be divided by residuary energy. Then the neighbour node with minimal value will be selected.
After ciphering the DVs, so the same procedure will be performed to happen the minimal value for concluding determination like as regular DSAP metric.
5.3.4 Proposed power cognizant DSAP Metric
To implement the proposed power cognizant DSAP metric, foremost the white-lie flag will be checked to happen out, the neighbour node has been chosen before or non? If so, so the proposed metric will be calculated DV and the white-lie flag for that node will be reset. Otherwise, the DV will be calculated by the same metric of the regular power cognizant DSAP metric. 18.104.22.168.The white-lie flag will be set when the protocol selected a neighbour node as the following hop. 22.214.171.124. shown the codification that the white-lie flag set.As the same as the regular power cognizant DSAP prosodies simulation, the other processs such as happening the neighbour nodes or happening the lower limit DV value, are the same as the regular DSAP metric simulation.
Chapter 6 Result and analysis
In order to prove the proposed metric, a simulation theoretical account of a stationary radio detector web included 12 nodes in 2D-4 nodes topology has been developed. From the simulation theoretical account, experiment has been carried out in order to obtain consequences. In the experiment, the beginning and finish are fixed which are Node 4 as beginning and Node 7 as finish ( see 6.1 ) .
As mentioned earlier in the old chapter, there are some premises made for the simulation theoretical account. They are listed below:
* The web simulates without any Base station node, which means the packages route internally between a beginning node to a finish node.
* Nodes in web know about their location and their neighbours location.
* Each node knows about available energy of its neighbours.
* The energy consumes by treating does non considered. Lone communicating including transmittal and having cost considered.
The simulation was ran with the initial energy 0.1 J for each node and it continued until the first node in the web died. 6.2 shows tendency of energy depletion in node 5 which was the first node died in this web simulation. The energy needed to convey and have a message is shown below.
From the simulation theoretical account, k = 512, vitamin D = 15,
The value obtained from the expression is the sum of energy needed by the detector nodes to convey a message ( ) and to have a message ( . These sums of energies are consumed by the nodes involved in the way at every unit of ammunition of the simulation. Every clip the node transmit or have a message, the sum of energy shown in No.1 and No.2 will be deducted from the current sum of energy that the node has. From the simulation theoretical account, the 3 different versions of the DSAP have different sum of clip for their first node to decease as shown in 6.2. This is due to the different prosodies used included the proposed metric.
As the graph shows in 6.2, all three prosodies had the same dramatically diminishing tendency until the unit of ammunition 2656 so the tendency of the proposed power cognizant DSAP metric at the 0.06 degree of energy is swimmingly changed to up because of the routing protocol used some other way alternatively of affecting the node 5 ever in the way. Therefore the node 5 saved more energy for communicating in the web.
As explained before in chapter 4 about the proposed power cognizant DSAP metric, the node ‘s residuary energy value will be divided by ? to the intent of stand foring untrue residuary energy for the node. This causes to forestall of taking the node 5 and affecting the other nodes to the way. In add-on, the proposed power cognizant DSAP metric makes this determination base on the figure of node engagement on the way, which is, if the node has been taken one clip before, so the new proposed metric will be chosen, otherwise, the regular power cognizant metric should be chosen.
Up to round 4426 the 2 original protocols had the same diminishing tendency and so the regular power cognizant metric tendency changed and continued with less grade until the node died, but the regular metric DSAP continued with consecutive tendency until the node died. The tendency of regular power cognizant metric changed because the metric looking for the most power node, hence, after that peculiar degree of energy, the regular power cognizant metric had chosen some other waies. Whereas, the regular metric DSAP ever choose the shortest way, therefore the node 5 involved in way 100 % .
From the experiment, it was found that first node died at unit of ammunition 8853 when the proposed power cognizant metric is used whereas, by utilizing the regular metric, the first node died at unit of ammunition 6377. As for the regular power-aware metric the first node died at unit of ammunition 8361 ( as shown in 6.3 ) . By utilizing the proposed power-aware metric, the web life clip could be increased up to 16 % .
The ground for the DSAP with the proposed metric to hold longer life-time is because of the factor that the neighbour node “lied” about the residuary energy of the next node which involved in the way. The proposed metric is mentioned in item in chapter 4.
On the other manus, 6.4 shows the figure of delivered message until the first node died. In this saloon chart, it is obvious that the proposed power-aware metric increased the figure of delivered messages compare to the other two prosodies.
Chapter 7 Conclusion and future work
In recent old ages, many routing protocols have proposed for WSNs, and implemented with different applications. One of the necessities in WSNs routing protocol that needs to be considered, is energy efficiency, because radio detector nodes have limited power in web, hence routing protocol demands to more see about node ‘s energy preservation. Many researches have been done to develop power cognizant routing protocols for radio detector webs in recent old ages. One illustration of a power cognizant routing protocol is the Directional Source Aware Routing Protocol ( DSAP ) which was developed with some power cognizant prosodies to protracting the web life-time.
Current power aware-DSAP metric most of the clip takes the neighbour ‘s node which has the most power with shortest way. Taking the peculiar waies causes to consuming energy in specific nodes in web and imbalanced power dissipation in web. Therefore, some nodes in the web stay untouched, whereas they could take part as a way to protracting the web life clip and besides increasing the figure of message bringing. If this job is solved, the life-time of the detector nodes can be prolonged.
In this research thesis, the metric proposed could assist equilibrating the web ‘s node energy dissipation by utilizing different nodes decently as the chosen way alternatively of utilizing some nodes more often.
Harmonizing to the new proposed metric, when a node has been used one clip before in way, it will take a new metric alternatively of utilizing the current power aware-DSAP metric. Otherwise, it takes the power aware-DSAP metric and finds the node to route. When the new metric be chosen, the neighbour node will state a prevarication about its staying energy to its parent beginning node, so the new metric evaluate by this untrue energy value. It could diminish the opportunity of taking that node, which has been taken one clip before. This new metric would name white-lie, because of the prevarication can assist the web to be survive for more clip. Hence, the web life clip will be addition, and besides other nodes will be use decently in way to increase the opportunity of message bringing.
Experiments shown that the proposed power cognizant metric increased the web life-time about 16 % , besides the figure of bringing messages increased excessively.
In decision, it can be said that, by utilizing the proposed power cognizant metric for DSAP routing protocol, the web life-time for a WSN can be increased. Therefore, the web can be survived more clip to aggregate more informations.
7.2 Future work
The proposed power cognizant metric for DSAP still has some countries to detect and make more research to better its public presentation. The parametric quantity ? is a value to happen the degree of residuary energy at node, nevertheless, the value ? =1.5 is non the best value and needs more analyzing to happen out an optimal expression to measure the best value for ? .
Testing the proposed power cognizant metric, in big graduated table web with different beginnings and finishs, is one of the other involvements that would be great to be tested. Besides, different web topologies such as 2D-8 Nodes or even 3D topology demands to be explored in the hereafter.
A.Salhieh, L. ( 2004 ) . POWER-AWAR