An Efficient Broadcast Algorithm To Transmit Data In Multi-hop Relay MANETs Fathima Sana 1, Dr. M. Sudheep Elayidom 2

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1 International Journal of Emerging Trends in Science and Technology Impact Factor: INC-BEAT 2016 An Efficient Broadcast Algorithm To Transmit Data In Multi-hop Relay MANETs Fathima Sana 1, Dr. M. Sudheep Elayidom 2 1 Final Year M.Tech Student, School of Computer Sciences, Mahathma Gandhi University,Kerala, fsana291991@gmail.com 2 Professor, Division Of Computer Science, Cochin University of Science and Technology, Kerala, sudheepelayidom@gmail.com ABSTRACT MANET can be defined as a collection of wireless mobile nodes where packets are transmitted from one node to another node via intermediate nodes that are in range. To find an efficient routing protocol, which is used to transmit data from source to destination across whole network, is a major issue in networking research. MANETs are flexibly distributed that can change their locations and self-configurable, so they are highly appealing for a lot critical applications, like disaster relief, deep space communication, battlefield communication, etc. In the Existing Broadcasting protocol, the parameters such as packet Delivery Ratio,end-to-end delay and retransmission rate are not yet close to achieve optimal performance due to the random selection of relay nodes. Relay node selected randomly may be opposite to the direction of destination. This relay node will then broadcast data to its range which will finally reach destination passing through a long path which increases delay and reduces the performance. So a new algorithm is further developed to select relay nodes with minimum distance to the destination. The time alloted for data transmission is 10% and time for acknowledgement retrieval is 90% in the existing system. In the new algorithm the time for data transmission has been increased to 30% and time for retrieving acknowledgement has been reduced to 70% for efficient transmission of data. Keywords-MANETs, Broadcasting, Multi-hop, Relay. 1. INTRODUCTION MANETs [7] (Mobile Ad hoc Networks), are the networks which are self configurable and can change their locations according to the requirement. Wireless connections are possible in MANETs as they are mobile. Broadcasting is the method of sending packet from a single node or multiple nodes to all nodes in the network. Broadcasting technique is widely used in MANETs routing protocol. In MANETs, major issue is to handle large scale networks, especially sending packet consistently with maximum throughput and minimum delay. We can achieve good performance of in point to point communication, but in multi hop relay network, the performance depends upon the number of hops. Efforts are done to improve broadcasting capacity and minimize end to end delay by finding optimal routing strategy. Traditional route based schemes like AODV[8], DSR[9] fail to function properly as they require number of links simultaneously. The dynamic and distributed MANETs are reconfigurable and vigorous. And they are useful in a lot of critical applications like disaster relief, deep space communication, outdoor mining, battle field communication etc. The study about delay performance and energy minimization have great importance to give guaranteed QOS(Quality of Service) to these applications. Each node in MANET[7] is considered as a route. Source sends packets to destination with the help of intermediate nodes, if it cannot send it directly. Nowadays, MANET network proposes bandwidth, Fathima Sana 1 Page 24

2 reliability and battery power and have peculiar traits like topology, transmission routes and signal strength. Many primary works has been done to analyze packet delivery and end to end delay. End to End delay is the major issue in multi-hop relay MANET. Reliable packet delivery without any loss is also mandatory in multi-hop relay MANETs. To find an optimal path in multi-hop relay network to deliver data to the destination is also an issue. Source will send packet in all possible paths which takes a lot of energy. Minimizing this energy consumption is a major challenge in multi-hop relay networks. Hence this paper proposes a multi-hop relay algorithm with improved performance for all these parameters. The rest of the paper is organized as follows:- Section II gives a study on existing broadcasting techniques. Section III proposes a new broadcasting algorithm for multi-hop relay MANETs, Section IV gives the results and discussion. Finally, Section V concludes the paper. modified or improved to use in multihop relay MANETs. 2.2 Broadcasting Using Cluster Approach. This paper [3] introduces cluster approach used in MANETs. Nodes are grouped into each clusters as in figure 1. There are cluster heads and gateways in this infrastructure for each clusters. Each cluster head forwards the packet to all clusters in its coverage with the help of gateways. Thus broadcasting is done between clusters in the MANET. It reduces collision, reduces delay, reduces energy consumption and improves the throughput. Building clusters is a good choice for collision free transmission but it is very costly which is considered as a demerit of this method. 2. LITERATURE REVIEW Several studies has been done for various broadcasting technique. Broadcasting means sending data to all nodes across the whole network simultaneously. 2.1 Broadcast Based Two Hop Relay MANETs. This paper [2] presents the potential application of QBD theory in MANETs delay analysis by applying it to the end to end modelling in a broadcast based two hop relay MANET. Eac node here is associated with three FIFS queues. They are : Source queue : This queue consist of the locally generated packets. Broadcast queue : This queue consist of packets which are broadcasted from the source S, but did not yet recieve the acknowledgement from the destination D. Relay queue: It consist of n - 2 flows. There are n distinct flows in the network out of which the flow starting from that node and destined to that node are omitted in the relay queue. This method is implemented in two hop relay MANETs but cannot be implemented in multi hop relay MANET. There is no reliable packet delivery in this method. So the above method should be Figure 1: Clustered Broadcasting 2.3 Competent Broadcasting in MANET. This paper [5] describes about the two broacasting algorithms in MANET. These algorithms are designed so as to get 100 % deliverability. Each node maintains one hop neighbour information. The two algorithms are :- Sender based algorithm Receiver based algorithm First, the time complexity of computing fowarding node is reduced to O(n) by sender based broadcasting algorithm. Then the highly efficient receiver based broadcasting algorithm where nodes are distributed uniformly are executed. When the distance between two neighbour nodes decreases or when the node density increases, the probability of broadcasting same messages are reduced. This is made possible using receiver based algorithm. Fathima Sana 1 Page 25

3 2.4 Neighbour Knowledge Based Broadcast In this paper [6], the broadcast based protocol tells about a reliable neighbour knowledge over QoS. The performance analysis was done in terms of four QoS metrics. They are packet delivery, end to end delay, packet loss probability and network control in multi hop relay MANETs. The algorithm used here is Scalable Broadcast Algorithm (SBA). Each node will have a perfect knowledge about their neighbours in this system. It was acheived by sending hello messages. These hello messages will contain both ip address of sending node and list of known neighbours. One hop and two hop neighbours are known from this method. When a node receives hello message it gets all its neigbour knowledge and two hop topology informations are also acheived. 2.5 Multi-hop Relay Broadcast Algorithm This paper [1], mainly focuses on an efficient broadcast algorithm in multi hop relay MANETs. MANETs are the networks with mobile nodes where data transmission takes place from one node to another via intermediate nodes. Here a unit torus MANETs were considered where every nodes are moving independently. These nodes have same radio power to transmit packet in the network. There are a total of n distinct flows in the network with n number of nodes. Each node act as a relay for all other n-2 flows in the multi hop relay network (excluding the flow which originates and which is destined from that node). Each node was associated with three First In First Served (FIFS) queues. They are: Source Queue: Consist of packets that are locally generated. Broadcast Queue: Consist of packets that are broadcasted, but their acknowledgement are not yet received. Relay Queue:There are n-2 relay queues which stores the packets of other n-2 flows (one for each flow). Source Node is defined as S and Destination Node as D (in Fig 2).S sends their locally generated packets to D via multiple intermediate nodes in the multihop relay network. In this multi-hop relay MANETs, the reliable data transmission or delivering data to D without any loss is very important. To find an optimal path to reach the destination is a major challenge in multi hop relay network. The other issue is to balance the energy constraint. 10% of the time slot was given to send data and 90% of the time slot was utilized to retreive acknowledgment. Figure 2: Multi-hop Broadcasting After transmission of data from S to D, source deletes the transmitted packet from source queue. This was done only if source retreives an acknowledgemnet from D. Then it is added to the broadcast queue at destination node. If there exist relay nodes, then it is added to the relay queue. Then the relay node sends the packet from relay queue to the destination D. D sends an acknowledgement back to realy node. After receiving the acknowledgement relay queue deletes the send packet and are added to the destination queue. If any link failure occurs, then it is recovered from source queue. But, since the packet is deleted from the source queue it cannot be resend to relay node R.While resending the packet, energy wastage occurs and transmission delay happens. 3. PROPOSED SYSTEM Broadcasting is the method of sending data from a single source or multiple source to all nodes in the network. Multi hop networks are the networks with multiple intermediate nodes between source and destination during the transmission of data. Multihop relay algorithm will provide better performance in terms of packet delivery ratio and optimise end to end delay. Network model introduced is with node mobility. Also modified multihop relay algorithm has been described for energy optimisation and reliable packet delivery. Fathima Sana 1 Page 26

4 3.1 Network models There are three network models. One is mobility and channel model where a unit torus MANET is partitioned evenly into m*m cells and there are n nodes roaming according to i.i.d. Second model is radio model where every transmitter have same radio power to transmit data. Third model is the traffic model where each node can act as both source and destination node of distinct traffic flows. 3.2 FIFS queues There are n distinct traffic flows. Each node act as relay for n-2 flows which excludes the flow originated and destined from itselves. In multi hop relay routing protocol operations are done using First In First Serve Queues (FIFS). They are : Source queue which is a local queue storing the locally generated packets. Broadcast queue which stores the packets that are already been broadcasted, but not yet retrieved acknowledgement from destination Relay queue which stores the packets from n- 2 flows( one for each flow) 3.3 Algorithm Let us consider S as source node and D as destination node as in figure 2. S will send its locally generated packet to destination D, via intermediate nodes. Out of these intermediate nodes, one will be selected as relay node (new source node) and it sends packet to its neighbours and so on. Thus it finally reaches destination. While sending packet to D, there is a chance of occuring reduntancy. To avoid this problem, in the designed multihop relay algorithm each node sends an acknowledgement to the source immediately when it receives the packet. Also the time required for sending packets is 30% of the time slot and 70 % of the time slot to retrieve acknowledgment in the designed algorithm which reduces data transmission energy. By this, reliable packet delivery is achieved. All the FIFS queues are updated for each flow. If any packet is lost in between then it can be recovered from the relay queue of sender relay node which increases the performance. Algorithm 1 : Multi-hop Algorithm 1: S checks whether its destination D is in the one-hop neighborhood; 2: if D is within the one-hop neighborhood of S then 3: S executes Source to Destination Transmission; 4: else 5: S selects source-to-relay transmission; 6: S executes Source to Relay Transmission; 7: end if Algorithm 2 : Source to Destination Transmission 1: S directly sends packet to D within 30% of time slot; 2: S waits for ACK within 70% of time slot; 3: if ACK not received then 4: S executes Source to Destination Transmission; 5: end if 6: S deletes packet from its source queue; 7: D updates the Broadcast queue; Algorithm 3 : Source to Relay Transmission 1: S randomly search for nearby relay node R out of one hop neighbors; 2: S directly sends packet to R within 30% of time slot; 3: S waits for ACK within 70% of time slot; 4: if ACK not received then 5: S executes Source to Relay Transmission; 6: end if 7: S deletes packet from its source queue; 8: R updates the Relay queue; 9: R is updated as new broadcasting source node S; The advantage of this algorithm is that, when a packet loss occurs it is resend by the nearest neighbour node and not by the initial source node. This method will reduce the energy usage and delay involved. Multihop relay algorithm optimizes data transmission energy, delay performance, packet delivery ratio in multihop relay MANET. 4. RESULTS AND DISCUSSIONS Fathima Sana 1 Page 27

5 When compared with AODV, it was found that implemented method have higher performance in terms of throughput and delay. Delay of the network =( packet arrival time- send time)/ number of nodes. Per node throughput is the average number of bits transmitted by each node to its destination in unit time. Throughput of the network can be defined as the sum of per node throughput of all nodes in the network. In AODV, it takes more time for communication establishment and route initialization. For a network with limited number of nodes it does not become a problem. But for large scale networks it consist of a large number of nodes. So AODV takes long time to transmit packet to its destination. In broadcasting, we can attain it with minimum delay as it does not require route establishment. In AODV there is no guarentee in packet delivery. But broadcasting algorithm proposed here gives a guarenteed packet delivery as the connection is reliable and gets an acknowledgement. 5. CONCLUSION The major issue in networking research was to find an efficient routing protocol to transmit data from source to destination across whole network. In the proposed algorithm it has only a lesser number of lines of codes and unwanted iterations are avoided here. This multihop algorithm gives high perfomance in packet delivery ratio and they optimizes delay perfomance in highly mobile multihop relay MANET. If any packet is lost in between transmission it can be resend from the nearby relay node which reduces energy consumption and improves the broadcasting capacity. REFERENCES [1] Dipali.K.Dakhole, Archana.R.Raut. An Efficient Broadcast Algorithm in Multi-hop Relay MANET,Fourth International Conference on Communication Systems and Network Technologies,2014 IEEE. [2] Juntao Gaot and Xiaohong Jiangt. Delay Modeling for Broadcast-Based Two-Hop Relay MANETs, 11th International Symposium and Workshops on Modeling and Optimization in Mobile, Ad Hoc and Wireless Networks (WiOpt), May 13-17, [3] D.Sivaganesan and Dr.R.Venkatesan. Performance Analysis of Broadcasting in Mobile Ad hoc Networks Using Cluster Approach, International Journal of Adhoc,Sensor and Ubiquitous Computing,Vol.1, No.2, June [4] Jiajia Liu, Juntao Gao, Xiaohong Jiang, Hiroki Nishiyama, and Nei Kato. Probing-Based Two- Hop Relay with Limited Packet Redundancy.13 th IEEE Conference on High Performance Switching and Routing (HPSR), Belgrade, Serbia, Jun [5] Ms. K. Vijayalakshmi,Mrs.S.Jeyanthi. Competent Broadcasting in MANET IEEE International Conference on Computational Intelligence and Computing Research. [6] Sumon Kumar Debnath and A.Z.M. Touhidul Analysis of Neighbour Knowledge Based Broadcast Protocol Performance for Multi-hop Wireless Adhoc Networks. International Journal on Ad Hoc Networking Systems (IJANS) Vol. 1, No. 2, October [7] MANET broadcasting Wikipedia Article [8] Durgesh Wadbude, Vineet Richariya, An Efficient Secure AODV Routing Protocol in MANET, International Journal of Engineering and Innovative Technology (IJEIT) Volume 1, Issue 4, April 2012 [9] Rajesh Sharma Seema Sabharwal, Dynamic Source Routing Protocol (DSR). International Journal of Advanced Research in Computer Science and Software Engineering. Fathima Sana 1 Page 28