IJBASS Volume I, Issue III, May 2013 International Journal of Basic Applied & Social Sciences An Interdisciplinary, Peer Reviewed, Indexed Journal
www.ijbass.caesjournals.org
Energy Efficient Routing Protocol in MANET using Power Management Method Suchismita Rout*1, Ashok Kumar Rout#2, Bibhudatta Sahoo#3 *
Department of Computer Sc. And Engineering Silicon Institute of Technology, Bhubaneswar # Department of Computer Sc. And Engineering National Institute of Technology, Rourkela 1
[email protected] 2
[email protected] 3
[email protected]
Abstract— Power management is an important concern in Mobile Ad Hoc Network, as a tethered energy infrastrastructure is unavailable and focus is to use the available battery energy efficiently. This power management approach helps in reduction of system power consumption and prolong the network lifetime. Balancing the power consumption is conjectured to postpone network partitioning by avoiding death of some critical nodes due to excess depletion of their energy. In this paper we introduce the concept of power management as a technique to reduce energy consumption in MANET. Routing is done in distinct alternative paths, in which no node is duplicated. This is controlled by clustering. In no traffic the cluster-heads make the nodes of that path in a sleep state to conserve energy; wasting in idle mode. It also maintains overall connectivity in network. We have simulated our proposed scheme using Qualnet 4.5 simulator. Simulation results shows that proposed approach has a good energy conservation performance and also performs better in context of average end-to-end delay without much affecting the throughput. Keywords— Alternate, APMC, Power management, end-to-end delay, throughput, clustering.
I. INTRODUCTION MANET has become increasingly popular in the computing industry [1]. They are dynamically formed, infrastructure-less, wireless multi-hop networks. A group of nodes can be deployed anywhere to establish the network connection instantly without the need of any base station. The nodes are mobile in nature; the packet is transferred from source to destination in dynamic networking environment where the topology of network is usually changes dynamically. These networks can withstand harsh environmental condition [2]. In order to facilitate communication within the network a routing protocol used to discover routes between nodes so that a packet can be delivered in an efficient manner [3]. In MANET all the nodes are powered by electro chemical batteries which are limited in nature [4]. As servicing and replacing batteries may not be feasible due to some limitation so for extending network life time some power aware criteria has taken considerable attention [5]. Power management is one of these techniques to minimize energy consumption in MANET. The main idea behind the power management approach is to trigger mobile nodes to low power mode from high power mode, when they are in idle state [6]. Power management basically decides when to switch off radio transceiver of mobile nodes to save energy. This power management state can also be called as sleep/power down
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mode [7]. In power management the mobile nodes require distributed coordination for communicating with other mobile nodes. For successful communication all mobile nodes communicate in such a way that it should not incorporate delays in packet transmission. The synchronization should be maintained in such a manner so that switching of one node should not affect the performance of overall network connectivity [8]. For this a control message is required to inform a sleeping node to wake up to be a part of network packet transmission. A node can be in one of two power management modes: active mode and power save mode. In active mode a node is actively participate in network activity. In power save mode a node sleep most of time and wakes of periodically to check any pending message. Power management approach plays an important role for minimizing energy and maximize network lifetime [9]. In our paper, we propose a new protocol, named Alternate Path-based Power Management using Clustering (APMC) protocol, to deal with power management issue at network layer and also help to reduce total energy consumption of network to maximize network lifetime. Rest of the literatures has been arranged as follows. Section 2 focuses on related work. Our proposed approach has been discussed in section 3 and its simulation behavior is compared with existing AODV protocol in section 4. It is followed by conclusions and acknowledgements in section 5 and 6 respectively. Finally references are listed in section 7. II. RELATED WORK Resource limitation, mobility of hosts and changing of wireless link make it difficult for MANET to manage for all quality of services. In spite of all these difficulties MANET is a good candidate for various military and civil applications. A lot of research works have been progressed in the area for energy conservation in MANET [10]. For efficient operations of network with the changing topology with the node mobility generates higher control message overhead. Methods to reduce energy consumption include: • Considering residual battery energy while selecting the route. • Reducing the communication overhead of control messages. • Efficient route reconfiguration mechanisms (effect in topology changes). Total energy consumption is divided into two parts. The former is E path-discovery and later Epacket-transmission. Epathis directly proportional to number of control packets. A node in packet transmission consumes energy in four states. Those are as follows: (a) transmit, (b) receive, (c) idle and (d) sleep. Highest power is consumed in transmit mode and least in sleep mode. Node does not do any useful work in idle mode. In idle mode the power consumption is as high as in receive mode. So in this mode energy is wasted unnecessarily. The principal sources of energy waste in MAC assume collision, message overhearing (receiving packets addressed for other nodes), and control packets overhead and idle listening. discovery
Etotal E path dis cov ery E packettransmission E path dis cov erycontrol packets
(1)
E packettransmission Eidle Eactive Esleep Etransient (2)
Eactive Erecv Etransmit
(3)
Esleep o Traditional routing protocol find the route depending upon the shortest path mechanism which is not appropriate for MANET, as a very small set of nodes are overuse rapidly in favour of others may cause network partitioning. To increase node and network life time the route is established by taking the lightly loaded nodes with sufficient power resources [11]. For longer network life and minimize energy consumption the basic solution to this problem is organized is three parts. • Power Management Approach • Power Control Approach
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• Topology Control Approach Energy conservation is achieved not by taking any solutions alone; it is possible by taking the combination of two or three techniques simultaneously. There are many researches carried out in order to reduce energy consumption in MANET. Some of them are explained as follows. A. DEAR Protocol DEAR stands for Device and Energy Aware Routing. DEAR protocol explains the use of device awareness to enhance energy efficiency in the routing. A node is assumed to be device aware if it is assumed to be powered by two states: internal battery power and external power source [12]. It assumes the cost of a node powered by external source is zero. The packets can be redirected to the powered node for power saving operations. An externally powered node has rich resource of power. It is capable of increasing its transmission power to a higher level so that it is easily reachable to any desired node in network in one hop distance. DEAR provides power saving by eliminating a number of hops which increases system life time, also average delay in packet receiving is minimized. B. SPAN Protocol Nodes in idle mode unnecessarily consume energy. To save energy it is better to put those nodes in sleep state without hampering network connectivity. For taking this decision a master node is selected. The SPAN protocol [13] employs a distributed approach to select a master node. The rule says that if two of its neighbours cannot reach each other either directly or via one or two masters, it should become a master. This rule does not yield the minimum number of master nodes. It provides robust connectivity with substantial energy savings. However, the master nodes are easily overloaded. To minimize this, the master node at any time withdraws as a master. It gives its neighbour node a chance to become a master if it satisfies master eligibility criteria. C. XTC Protocol The XTC topology control algorithm [14] works without either location or directional information. The algorithm has three phases. In first one each node broadcast at maximum power. Then it ranks its entire neighbour depending upon its link quality to it. The link quality could be the Euclidean distance, signal attenuation or packet arrival rate depending on various situations. In second steps each node transmits its ranking results to neighbouring nodes. In the final one, each node examines the ranking results of its neighbours. Depending upon this result it select neighbour to be linked directly. The XTC algorithm follows both symmetry and connectivity feature of topology control. It runs faster as compare to other algorithms. D. LFTC Protocol The LFTC protocol [15] constructs power-efficient network topology. It also avoids any potential collision due to hidden terminal problem. It works in two phases: link determination phase and interference announcement phase. In first phase each node broadcasts hello message with vicinity table. This table is attained by every other node in network. Each node adjusts its transmission power Pdata to communicate with all its direct neighbours. The set of its direct neighbours is called direct communication set (DCS). The second phase avoids data collision due to hidden terminal problem. This is done by taking appropriate power for P data and Pcontrol. This results in two simultaneous data transmission in networks without any interference. The LFTC protocol has smaller hop count, low control packet overhead and low ratio of collision as compare to XTC. E. In C. F. Chiasserini et. all In this paper [9] energy savings in wireless ad hoc network is maximized using power management scheme. They assume battery powered devices can be activated remotely by a wake-up signal using a simple circuit based RF tag technology. Devices that are not active currently enter a sleep state and power off if they have pending traffic. Sleep pattern is used to enter different sleep states depending on their battery status and quality of service. From which radio devices can select different time-out values. III. PROPOSED APPROACH In this chapter we propose the problem of network partition caused due to earlier death of some node caused by heavily utilization in network connectivity as compare to other nodes in network. By routing the packets through the shortest path some group of nodes are used rapidly. To eliminate this problem and make connectivity intact for a longer period of time we propose routing should be carried by distinct alternative paths and for its efficient operation it is controlled by clustering. The protocol environmental assumptions are described as follows: 1. We are considering two dimensional homogeneous networks where all the nodes have limited battery power and similar capabilities. Each node has its own ID and communicates through Omni directional antenna. 2. All nodes in network have same transmission range. The transmission medium is symmetric.
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Let G= (V, E) represents a network where V is the set of mobile nodes and E is the set of connections between the nodes. Let Puv denotes the minimum power required for node u to communicate directly to node v. As the medium is symmetric so Puv = Pvu. In the dynamic network the cardinality of the nodes |V| remains constant but due to mobility nature of the nodes the cardinality of links |E| may varies. Our protocol consists of two phases, the first phase is path establishment phase, and second is clustering phase. In path establishment phase we propose an algorithm to find the number of possible distinct alternative paths in a network. We assume that by running our algorithm more than one distinct alternative path can be found out. We limit the maximum number of paths to three, as more number of paths needs more control mechanism causing unnecessary energy consumption. In the second phase we divide the network logically into number of clusters. Each cluster is having one cluster head which control the routing through alternative path so that overall traffic of network is shared and efficient network connectivity can be achieved. It also minimizes the total energy consumption in network by making the idle mode node to be in sleep state. A. Path Establishment Phase Initially all the nodes are deployed in an area to establish network connectivity. In the first phase a node randomly broadcast the hello message once using the power Pmax. It is the constant transmission power of each node. The initial energy level of all nodes is assumed to be same [15]. The node sends the hello message by appending its ID to the nodes present in its neighbour. The receiver collects all the information from the hello message of its neighbour. It collects all these information to make its adjacent list. This list contains the list of neighbour nodes of a particular node. For example in Fig. 1. node 1 sends the hello message as given in Table 1. The neighbour in its transmission range listens to this hello message. Node 1 collects the hello message from its neighbour nodes and prepares its adjacent list as given in Table 2. Table 1 Hello Message of Node 1
Hello
1
Fig. 1 A Network Structure Table 2 Adjacent list of Node 1
Node 1
Adjacent list 2, 4, 5, 6
Table 3: Adjacent List
Node 1 2 3 4 5 6
Adjacent list 2, 4, 5, 6 1, 4 6 1, 2, 5, 7 1, 4, 8 1, 3, 9
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7
4, 8, 10
8
5, 7, 9, 11
9
6, 8, 12
10
7, 13, 14
11
8, 14
12
9, 14, 15
13
10, 14
14
10, 11, 12, 13, 15
15
12, 14
In similar way for every node we can find out the neighbour nodes and make the adjacent list of network as given in Table 3. Algorithm for finding path ( ): 1. Initialize all nodes of network to ready state (Status=1). 2. Put the source node in queue and change its status to waiting state (status=2). 3. Repeat step 4 to 6 until queue is empty or destination is reached. 4. Process front node N of queue and change its status=3. front=front+1 5. Add at rear end of queue all the neighbour's of N that are ready state and change their status to waiting state (status=2). rear=rear+1. Don't add repeated nodes. 6. As neighbours are added keep track of their origin. End of step 3. 7. As destination is reached stop and find the path traversing from destination in a reverse order by tracking the origin till source node at origin is reached. Then switch off all nodes coming in the path to reduce energy conservation due to idle state. 8. Go to step 3 and process to front node. 9. Exit. After getting the adjacent list the path finding procedure starts. By running our algorithm we have 3 distinct alternate paths. They are: 1→4→7→10→14 1→5→8→11→14 1→6→9→12→14 Since any of these three paths no node is duplicated, so no node is heavily penalized. As more than one path is used for data transmission so there is no queue overflows for any path. After getting the alternate paths the clustering phase starts. In no traffic the cluster head take care of energy of network by putting the idle mode node in sleep state. B. Clustering Phase: After path establishment phase the clustering phase starts. In this phase a network is logically divided into number of clusters. For cluster formation we use Least Cluster Change algorithm (LCC) [7]. As cost of cluster maintenance is considered LCC has significant improvement over LIC and HCC [8]. To start clustering each node broadcast its ID and degree to the nodes within its transmission range. The node having the highest degree is elected as cluster head. The neighbour of a cluster-head becomes the cluster members. In case of two nodes having same number of highest degree, the cluster head is elected based on LIC scheme. The node with the lowest ID is elected as cluster
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head. Once the first cluster is formed the cluster head and its members can no longer participate in the election process. The cluster formation for the other nodes in network follows the same process. Following this clustering process node 1 transmits its ID and degree to its entire neighbour in its transmission range. Its neighbours also transmit the ID and degree among each other. Each node has the information about the degree of their neighbour. Among these neighbours, nodes 1 and 4 have the highest degree. Using HCC algorithm both the node 1 and 4 will be the cluster head. Using LIC algorithm the least cluster ID 1 is elected as the first cluster head. Its neighbour becomes its cluster members. Node 1 and its cluster members become the first cluster and don’t participate in further cluster election process. Following the same process the other cluster are formed and its cluster-head is elected. Node 8 becomes the second cluster-head with its cluster member’s node 7, 9 and 11. The third cluster is formed with the cluster-head node 14 and its members 10, 12, 13, 15. C. Working Phase After getting alternate paths in a network, we go for clustering phase. Each cluster head has information regarding the alternate paths. The cluster heads can exchange their information between them at any point of time by broadcasting messages between cluster-heads. When packet starts transferring in one path the cluster-head make the nodes of that path active. In case of heavy traffic the cluster head balance the load by transferring it in different paths. Since any of these three paths no node is duplicated, so no node is heavily penalized and since more than one path is used for data transmission so there is no queue overflow for any path. In no traffic the cluster head take care of energy of network by putting the idle mode node in sleep state. So by this overall energy consumption of whole network is lessening. IV. SIMULATION AND RESULTS A. By Varying Number of Packets: The performance of our proposed algorithm is compared with that of existing (AODV) algorithm through simulation. For simulation, we have considered Qualnet 4.5 simulator. Performance metrics considered for comparison are: (1) Energy consumption vs. no. of packets sent (2) End to end delay vs. no. of packets sent and (3) Throughput vs. no. of packets. Parameters considered for simulation is shown in Table 4. Table 4 Simulation Parameters
Parameter Terrain Co-ordinates Simulation Time Maximum nodes Routing protocol Traffic Item size Interval time of item sending
Value 1000, 1000 m2 30 min 8 AODV CBR 512 bytes 1 sec
In Fig. 2, we plot the graph for energy consumption vs. number of packets. It is observed from the figure that the energy consumption in our proposed scheme is lesser than that of the existing approach. This is because in proposed scheme we are taking alternate paths to transfer packets in which no node is duplicated in any of these paths. The overall traffic is shared equally among all the nodes, which is not in the case of
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Fig. 2 Total Energy consumption Vs. No. of Packets
existing approach in which the packets travel in one path, causing maximum energy consumption of the nodes in that path.
Fig. 3 Average end-to-end delay Vs. No. of Packets
Fig. 4 Throughput Vs. No. of Packets
In Fig. 3, we plot the graph for end to end delay vs. number of packets. It is observed from the figure that the end to end delay in proposed scheme is lesser than that of the existing approach. This is because in proposed scheme the
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traffic is shared equally among all the alternate paths. No node is heavily used, so the delay in packet reception is minimized. In Fig. 4, we plot the graph for throughput vs. no. of packets. It is observed from the figure that the throughput in our proposed scheme almost same as that of existing scheme for up to 800 packets after that it starts decreasing. B. By Varying Mobile speed: In this simulation we are varying the speed of mobile by keeping no. of packets constant at 1000. Performance metrics considered for comparison are: (1) Energy consumption vs. maximum speed (2) End to end delay vs. maximum speed and (3) Throughput vs. maximum speed. Parameters considered for simulation is shown in Table 5. Table 5 Simulation Parameters
Parameter Terrain Co-ordinates Simulation Time Maximum nodes Routing protocol Traffic Item size No. of Packets
Value 1000, 1000 m2 30 min 8 AODV CBR 512 bytes 1000
In Fig. 5, we plot the graph for energy consumption vs. maximum speed. It is observed from the figure that the energy consumption in our proposed scheme is lesser than that of the existing approach. This is because in proposed scheme we are taking alternate paths to transfer packets in which no node is duplicated in any of these paths. The overall traffic is shared equally among all the nodes which are not in the case of existing approach.
Fig. 5 Total energy consumption Vs. Maximum Speed
In Fig. 6, we plot the graph for end to end delay vs. maximum speed. It is observed from the figure that the end to end delay in proposed scheme is lesser than that of the existing approach. This is because in proposed scheme the traffic is shared equally among all the alternate paths. No node is heavily used, so the delay in packet reception is minimized.
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Fig. 6 Average end-to-end delay Vs. Maximum Speed
In Fig. 7, we plot the graph for throughput vs. maximum speed. It is observed from the figure that the throughput in our proposed scheme lesser than that of existing scheme for 1000 packets. This is because some packets may be lost in transferring the control between one path to another in proposed approach.
Fig. 7Throughput Vs. Maximum Speed
V. CONCLUSIONS In this paper, we propose a two-phase APMC protocol which deals with power management approach to minimize energy consumption of a network. In power management energy is conserved by making the idle mode node to be in sleep state. Routing is done in such a way so that packet can be transferred by minimizing delay. In APMC the packet is transferred in distinct alternative paths. To avoid delays and proper synchronization it is controlled by clustering. The network is logically divided into number of clusters. The cluster head in a cluster maintains connectivity within a network. When packet starts transferring in one path the cluster head make nodes of that path active and other nodes in sleep state if not in use. In case of heavy traffic the cluster head transfer it in different paths. The proposed APMC protocol is compared with AODV using Qualnet 4.5 simulator. Simulation results proved that APMC protocol has good energy conservation performance. APMC also performs better in terms of average end-to-end delay without much affecting the throughput. Delay is minimized as packet is transferred in distinct alternative paths. ACKNOWLEDGMENT
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This research was supported by project grant Vide No: 13(1)2008-CC&BT of Ministry of Communication & Information Technology, Dept of IT, Government of India, titled ― Energy Aware Protocol for Wireless Networks‖ and being carried out at department of Computer Science and Engineering, NIT Rourkela. REFERENCES [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15]
M.Iiyas and I.Mahgoub. Mobile Computing Handbook. CRC Press, 2005. S. Rout, A.K. Turuk and B. D. Sahoo, ―Energy Efficiency in Wireless Network: Through Alternate path Routing‖, in proceedings of Fourth Innovative conference on Embedded Systems, Mobile Communication and Computing, 3-8, July 2009. S. Rout, A. K. Turuk and B. D. Sahoo, ―Energy Efficiency in Wireless Ad hoc Network using Clustering‖, in proceedings on 12th International Conference on Information Technology,223-226, December 2009,. S. Rout, A. K. Turuk and B. D. Sahoo, ―Energy Aware Routing Protocol in MANET using Power Efficient Topology Control Method‖, 43(5): 33-42, April 2012. M. Woo, C. Singh, and C.S. Raghavendra. Power-aware routing in mobile ad hoc networks. Proceedings inFourth Annual ACM/IEEE International Conference on Mobile Computing and Networking, Texas, USA,181–190, January 1998. N. Tantubay, D. R. Gautam and M. K. Dhariwal, ―A Review in Power Conservation in Wireless Mobile Adhoc Network(MANET)‖,Proceedings in International Journal of Computer Science Issues, 8(4): 378- 383, July 2011. Ching-C. Chiang, Hsiao-K. Wu, W. Liu and M. Gerla, ―Routing in Clustered Multihop, Mobile Wireless Networks with Fading Channel,‖ in proceedings of IEEE SICON’97, 1997 ] M. Gerla and J. T. Tsai, ―Multiuser, Mobile, Multimedia Radio Network,‖ Wireless Networks, vol. 1, 255–65, October 1995 C. F. Chiasserini, and R. R. Rao, ―A Distributed Power Management Policy for Wireless Ad Hoc Networks‖, Proceedings in IEEE Wireless Communications and Networking Conference, Vol.-3: 1209-1213, 2000. Yu Wang, ―Study on Energy Conservation in MANET‖, JOURNAL OF NETWORKS, 5(6): 708-715, June 2010. N. Gupta and S. R. Das. ―Energy-Aware On-Demand Routing for Mobile Ad Hoc Networks‖. Proceedings of the4th International Workshop on Distributed Computing, Mobile and Wireless Computing, Lecture notes in computer Science, 2571: 164-173, January 2002. A. Avudainayagam, W. Lou, and Y. Fang. ―DEAR: A Device and Energy Aware Routing protocol for Heterogeneous Ad Hoc Networks‖. Proceedings in Academic press Journals of Parallel and Distributed Computing, 63(2): 228-236, February 2003. B. Chen, K. Jamieson, H. Balakrishnan, and R. Morris. ―Span: An Energy-Efficient Coordination Algorithm for Topology Maintenance in Ad Hoc Wireless Networks‖. Proceedings in Academic Publishers of Wireless Networks, 8(5): 481-494, September 2002. S. Banerjee and A. Misra, ―XTC: A Practical Topology Control Algorithm for Ad-Hoc Networks‖. Proceedings in 18 th International Symposium on Parallel and Distributed Processing, Switzerland, 216- 223, April 2004. J.-P. Sheu, S.-C. Tu, and C.-H. Hsu, ―Location-Free Topology Control Protocol in Wireless Ad Hoc Networks‖. Computer Communications, 31(14): 3410-3419, 2008.
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