Performance Analysis of DSDV, AODV, DSR and OLSR MANET Routing Protocols

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1 International Journal of Applied Science & Technology Research Excellence Vol. 5 Issue 1, Jan.- Feb. 215, Performance Analysis of,, and MANET Routing Protocols Sunil Malik #1, Dr. K.P Yadav *2, #1 Research Scholar, Singhania University, Pacheri Bari, Rajasthan , India * Director, Mangalmay Institite of Engg. & Tech., Greater Noida, U.P. Abstract MANET is a peer to peer, multi-hop mobile wireless networks in which packets are transmitted in store and forward manner from source to destination. A mobile ad hoc network (MANETs) is a network formed by a set of mobile hosts which communicate among themselves by means of the wireless mediums. This type of self organizing network combines wireless communication with a high degree node mobility. A number of ad hoc routing protocols have been developed during the time, but none of these is able to produce efficient routing of packets in large number of nodes due to their own limitations. In this paper, we presented our observations regarding the comparison of the four MANET routing protocols, Ad hoc On Demand Distance Vector (), Dynamic Source Routing (), Destination-Sequenced Distance-Vector Routing protocol () and Optimized Link State Routing (). We perform extensive simulations, using NS-2 simulator. Our studies have shown that reactive protocols perform better than proactive protocols. Further Dynamic Source Routing has performed well for the performance parameters namely delivery ratio and routing overload while performed better in terms of average delay. Keywords MANET,,,,, NS-2, RFC, CBR, VBR. Introduction A mobile ad hoc network (MANET) is a self-organizing and self configuring multi-hop wireless network, where the network structure changes dynamically due to node mobility. Ad hoc wireless network are self creating and self administrating. The nodes are free to move randomly and organize themselves arbitrarily. Hence, these networks are formed when needed. All available nodes are aware of all other nodes within range. The entire collection of nodes is interconnected in many different ways. The topology of such networks changes very rapidly because the nodes in ad hoc network are mobile and independent of each other. This makes the routing very difficult. With the popularity of Ad-hoc networks, many routing protocols have been designed for route discovery and route maintenance. They are mostly designed for best effort transmission without any guarantee of quality of transmissions. In our paper we have evaluated performances of most widely used MANET routing protocols namely,, and for Variable Bit Rate traffic in MANET using NS-2, which is a discrete event simulator. Our study has shown that reactive protocols perform better than proactive. Also has performed better than in terms of Delivery Ratio and Routing Overload while performed better in terms of Average Delay. Paper Outline This paper is distributed as follows In section 2 we have discussed about previous such works. Section 3 gives details about current emerging energy efficient routing protocols. Section 4 analyses and compares the different energy efficient routing protocols. Section 5 summarizes this paper. 2. Related Work A MANET is a most promising and rapidly growing technology which is based on a self- Page 22

2 International Journal of Applied Science & Technology Research Excellence Vol. 5 Issue 1, Jan.- Feb. 215, organized and rapidly deployed network. Due to its great features, MANET attracts different real world application areas where the networks topology changes very quickly. The IETF MANET working group mandate was to standardize IP routing protocols in MANETs. The RFC 251 specifies the charter for the working group. The RFCs still has unanswered questions concerning either implementation or deployment of the protocols. Nevertheless, the working group identifies the proposed algorithms as a trial technology. Aggressive research in this area has continued since then, with prominent studies on routing protocols such as Ad hoc On-demand Distance Vector (), Destination-Sequenced Distance-Vector Routing protocol () and Dynamic Source Routing Protocol (). Several studies have been done on the performance evaluation of routing protocols based on CBR traffic pattern using different evaluation methods. Different methods and simulation environments give different results and consequently, there is need to broaden the spectrum to account for effects not taken into consideration in a particular environment. It is observed that most of the research work is based on CBR traffic pattern whereas most of the traffic approximately 95% on the Internet carries TCP [1]. It is desirable to study and investigate the performance of different MANET routing protocols under both CBR and TCP traffic patterns. In this paper, we will evaluate the performance of, and protocols of mobile ad-hoc network routing protocols for TCP traffic pattern. The performance of these routing protocols can be evaluated with respect to various parameters such as Packet Delivery Ratio, Throughput and Jitter. There are many discrete-event network simulators available for the MANET community. Simulator used to simulate the ad hoc network routing protocols is the Network Simulator-2 (ns-2.34 version. Nodes in the simulation are moved according to random way mobility model. The authors in [2] [3] [4] [5] use constant bit rate (CBR) for their analysis. Most of the previous work is limited on performing simulations for ad hoc networks with a CBR. Our work differs in that we use variable bit rate (VBR). 3. Wireless Ad hoc Routing Protocols In this section we briefly describe the protocols that we investigate. A detailed discussion and comparison of most popular wireless ad hoc routing algorithms is available in [6]. Protocol Destination-Sequenced Distance-Vector Routing () is a table-driven routing scheme for ad hoc mobile networks based on the Bellman Ford algorithm. This protocol is based on classical Bellman-Ford routing algorithm designed for MANETS. Each node maintains a list of all destinations and number of hops to each destination. Each entry is marked with a sequence number. It uses full dump or incremental update to reduce network traffic generated by rout updates. The broadcast of route updates is delayed by settling time. The only improvement made here is avoidance of routing loops in a mobile network of routers. With this improvement, routing information can always be readily available, regardless of whether the source node requires the information or not. solve the problem of routing loops and count to infinity by associating each route entry with a sequence number indicating its freshness. In, a sequence number is linked to a destination node, and usually is originated by that node (the owner). The only case that a non-owner node updates a sequence number of a route is when it detects a link break on that route. An owner node always uses even numbers as sequence numbers, and a non-owner node always uses odd-numbers. With the addition of sequence numbers, routes for the same destination are selected based on the following rules: (i) A route with a newer sequence number is preferred. Page 23

3 International Journal of Applied Science & Technology Research Excellence Vol. 5 Issue 1, Jan.- Feb. 215, (ii) In the case that two routes have a same sequence number, the one with a better cost metric is preferred [7]. Each route update packet, in addition to the routing table information, also contains a unique sequence number as-signed by the transmitter. The route labeled with the highest (i.e. most recent) sequence number is used. If two routes have the same sequence number then the route with the best metric (i.e. shortest route) is used. Based on the past history, the stations estimate the settling time of routes. The stations delay the transmission of a routing update by settling time so as to eliminate those updates that would occur if a better route were found very soon. To damp the routing fluctuations due to unsynchronized nature of periodic updates, routing updates for a given destination can propagate along different paths at different rates. To prevent a node from announcing a routing path change for a given destination while another better update for that destination is still in route, requires node to wait a settling time before announcing a new route with higher metric for a destination. Protocol The joins the mechanism of and. The hop-by-hop routing and sequence number of and on-demand mechanism of route discovery and route maintenance from are combined in [1]. In this when the route is present in cache, route discovery is not used. Otherwise the RREQ which contains the last known sequence number, is flooded in network. The intermediate nodes store the reverse route to source. When destination gets the RREQ, it sends back RREP that contains number of hops to it and most recent sequence number. All intermediate nodes that forward the RREP backward build a forward path. Because of the hop-by-hop nature of the nodes store only the next hop instead of entire route. Route To maintain routes the nodes check link status of their next hop neighbour in active routes. The node, detecting a link break sends a route error (RERR) message to each of its upstream neighbour to invalidate this route and the neighbours forward it further. Consequently, these nodes propagate the RERR to their predecessor nodes. This process continues until the source node is reached. When RERR is received by the source node, it can either stop sending the data or reinitiate the route discovery mechanism by sending a new RREQ message if the route is still required. An important feature of is the maintenance of timer based states in each node, regarding utilization of individual routing table entries. A routing table entry is expired if not used recently. A set of predecessor nodes is maintained for each routing table entry, indicating the set of neighboring nodes which use that entry to route data packets. These nodes are notified with RERR packets when the next-hop link breaks. Each predecessor node, in turn, forwards the RERR to its own set of predecessors, thus effectively erasing all routes using the broken link. Route error propagation in can be visualized conceptually as a tree whose root is the node at the point of failure and all sources using the failed link as the leaves [11]. Protocol stands for Dynamic Source Routing [12]. It is also reactive routing protocol in which path is created on demand i.e. when it is needed. use source routing in which the source node indicates the sequence of intermediate nodes to reach the destination. The route discovery and route maintenance is same in as in except that it does not use backward learning. The source node sends RREQ (Route Request) as broadcast node to its neighboring nodes. The header of the query packet carries the Ids of intermediate nodes through which it travels. The destination on receiving RREQ packet sends with RREP (Request reply) packet to the destination. It uses the reverse Page 24

4 International Journal of Applied Science & Technology Research Excellence Vol. 5 Issue 1, Jan.- Feb. 215, of path that was stored in the RREQ packet. The source node receives the path to the destination from the RREP message. The source may receive more than one route that it stores in cache. Now, the source node copies the path to the destination in each data packet to be sent to destination. The packets follow the path mentioned by the source. In case the route fails. The intermediate node sends RERR (Route Error) message to the source. The source then uses another path stored in the cache if it has multiple routes stored. Otherwise the route discovery is done again. The advantages of the protocol are that use of cache decreases the latency, speeds up route discovery and decreases overhead as multiple routes are stored in cache. The drawback of this protocol is that as the data packet contains the full routing information that increases overhead. The outdated routes in the cache also affect the performance as they may be no longer valid paths. Protocol Clausen and Jacquet proposed the Optimized Link State Protocol, a point-to-point proactive protocol that employs an efficient link state packet forwarding mechanism called multipoint relaying [8, 9]. It optimizes the pure link state routing protocol. Optimizations are done in two ways: First, by reducing the size of the control packets and by reducing the number of links used for forwarding the link state packets. Here each node maintains the topology information about the network by periodically exchanging link-state messages among the other nodes. is based on the following three mechanisms: neighbor sensing, efficient flooding and computation of an optimal route using the shortest-path algorithm. Neighbor sensing is the detection of changes in the neighborhood of node. Each node determines an optimal route to every known destination using this topology information and stores this information in a routing table. The shortest path algorithm is then applied for computing the optimal path. Routes to every destination are immediately available when data transmission begins and remain valid for a specific period of time till the information is expired. Secondly, it minimizes flooding of this control traffic by using only the selected nodes, called multipoint relays, to diffuse its message in the network. Only the multipoint relays of a node retransmit its broadcast messages. This technique significantly reduces the number of retransmissions in a flooding or broadcast procedure [13][14][15]. Simulation Environment The simulation study is to analyze the performance of,, and routing protocols in Wireless MANET Networks environment. The simulations have been performed using Network Simulator 2 version 2.34, a software that provides scalable simulations of Wireless Networks and an open source software. In our simulation, we consider a network within a 8m X 8m area and operating over 75 seconds. Multiple runs with different node speed and number of nodes are conducted for each scenario and collected data is averaged over those runs. To evaluate the performance of routing protocols, both qualitative and quantitative metrics are needed. Most of the routing protocols ensure the qualitative metrics. Therefore, we use different quantitative metrics to compare the performance. We have used Average Delay, Delivery Ratio and Normalized Routing Overload as performance parameters while varying various network parameters such as Pause Time, Burst Time. 4 Simulation and Results and Analysis In this section we present our simulation efforts to evaluate and observations that compare the Page 25

5 Average Delay Delivery Ratio Routing Overhead International Journal of Applied Science & Technology Research Excellence Vol. 5 Issue 1, Jan.- Feb. 215, performance of the protocols that we described previously in Section 3. Effect of Varying Pause Time As in MANETs nodes are move from one position to other position. Time for which a node waits on a first destination before moving to second destination is called Pause Time. We used this as a parameter as it is measure of mobility of nodes. Low pause time means node will wait for less time thus giving rise to high mobility scenario. Figure 1, 2 and 3 shows various performance parameters v/s pause time when other parameters were constant. From figure we can observe that normalized overload for and is almost constant. This is because of their proactive nature due to which they offer constant routing overhead in all cases. While for reactive protocols considered here as we increased pause time routing overload has decreased.this is because as routing pause time increases mobility decreases and thus link breakage become rare which in turn will decrease number of route request from sources and hence decreasing overhead. Also outperformed as it maintains multiple routes to a destination. In case of failure in one route other route will be used rather than initiating route request. Also from figure we can see that average delay for proactive protocol was better at high mobility as they use route already in the table, and no time is required to find route as opposite to reactive protocols as they will wait for route formation. But at lower mobility, we can observe that reactive protocols performed better in terms of average delay among which outperformed. This is because may not use optimum path always unlike Pause Time Figure 1 Routing Overload versus Pause Time (ms) Pause Time Figure 2 Delivery Ratio versus Pause Time (ms) c Pause Time Page 26

6 Delivery Ratio Routing Overload International Journal of Applied Science & Technology Research Excellence Vol. 5 Issue 1, Jan.- Feb. 215, Figure 3 Average Delay (ms) versus Pause Time (ms) Effect of Varying Burst Time Burst time is the average times between two packet traffic bursts on observe in a determined simulation. The burst time may be another varying parameter. It plays important role in performance. Figure 2, 3 and 4 shows various performance parameters versus Burst Time. From figure we can observe that routing overload for all protocols decreased with increase in burst time with performing better than others. For reactive protocols route expiry has become less common thus reducing routing overload while for proactive which give constant overload irrespective of load, increasing burst increased data packet thus reduced normalized overhead. Also from graph it can be seen that with increase in burst time delivery ratio decreases for all protocols as queue overflow might have started. In this case has outperformed all. When traffic arrives in bursts would operate route discovery for the first packet. Hence, the rest of the load (of the same burst) would follow the same path. Consequently there is non-increasing of control load (no new route discovery is needed). On the other hand, continues insist in keeping the same routing tables even when only few routes (burst routes) are in fact used for transmission. In this case performed better than others Burst Time Figure 4 Routing Overload versus Burst Time (ms) Burst Time Figure 5 Delivery Ratio versus Burst Time (ms) Page 27

7 Average Delay International Journal of Applied Science & Technology Research Excellence Vol. 5 Issue 1, Jan.- Feb. 215, Burst Time (ms) Figure 6 Average Delay (ms) versus Burst Time (ms) 5. Conclusions In this paper, the performance of the four MANET Routing protocols such as,, and was analyzed using NS-2 Simulator. We have done comprehensive simulation results of Average Endto-End delay, throughput, and packet delivery ratio over the routing protocols,, and by varying network size, simulation time. and are reactive protocol while and are proactive protocols. is a proactive routing protocol and suitable for limited number of nodes with low mobility due to the storage of routing information in the routing table at each node. Both and performed well in high mobility scenarios than proactive protocol. High mobility result in highly dynamic topology i.e. frequent route failures and changes. Both and fail to respond fast enough to changing topology. One of the advantages of proactive protocols on ad-hoc networks ( and, for example) is no need r central management to handle the routing process, in contrast to regular and almost permanent routing tables required by those table driven protocols. Comparing with and protocol, byte overhead in each packet will increase whenever network topology changes since protocol uses source routing and route cache. Hence, is preferable for moderate traffic with moderate mobility. As routing protocol needs to find route by on demand, End-to-End delay will be higher than other protocols. produces low end-to-end delay compared to other protocols. When the network load is low, performs better in case of packet delivery ratio but it performs badly in terms of average End-to-End delay and throughput. protocol is proactive or table driven in nature, hence it favors the networking context where this all time kept information is used more and more, and where route requests for new destinations are very frequent. The protocol also goes in favor of the applications which do not allow long delays in transmitting data packets. protocol is adapted to the network which is dense, and where the communication is assured to occur frequently between a large numbers of nodes. References [1] Clausen T., Jacquet P., Viennot L. (23), Comparative study of CBR and TCP performance of MANET routing protocols, France: Project HiPERCOM INRIA. [2] Ioannis Broustis, Gentian Jakllari, Thomas Repantis, and Mart Molle, A Comprehensive Comparison of Routing Protocols for Large-Scale Wireless MANETs, [3] J. Broch et al., A Performance Comparison of Multihop Wireless Ad Hoc Network Routing Protocols, Proc. IEEE/ACM MOBICOM 98,Oct.1998, pp [4] Jiwei Chen, Yeng-Zhong Lee, Daniela Maniezzo, Mario Gerla, Performance Comparison of and OFLSR in Wireless Mesh Networks, [5] Yangcheng Huang, Saleem Bhatti, Søren-Aksel Sørensen, Adaptive MANET Routing for Low Page 28

8 International Journal of Applied Science & Technology Research Excellence Vol. 5 Issue 1, Jan.- Feb. 215, Overhead, 27-hbs27.pdf. [6] Arun Kumar B. R., Lokanatha C. Reddy, Prakash.S.Hiremath, MOBILE AD HOC NETWORKS: ISSUES, RESEARCH TRENDS AND EXPERIMENTS, International Engineering & Technology (IETECH) Journal of Communication Techniques, Vol. 2, No. 2, 57-63, 28. [7] C.E. Perkins & P. Bhagwat, Highly Dynamic Destination Sequence - Vector Routing () for Mobile Comput-ers, Computer Communication Review, vol. 24, no.4, 1994, pp [8] L. Abusalah, A. Khokhar and M. Guizani, A Survey of Secure Mobile Ad Hoc Routing Protocols, IEEE Communications Surveys & Tutorials, vol. 1 no. 4, 4th Quarter 28. [9] T. Clausen, P. Jacquet, A. Laouiti, P. Muhlethaler, A. Qayyum, L.Viennot, Optimized link state routing protocol for ad hoc networks, in: Proceedings of IEEE INMIC, December 21, pp [1] Dynamic Source Routing (): [11] Ioannis Broustis, Gentian Jakllari, Thomas Repantis, and Mart Molle, A Comprehensive Comparison of Routing Protocols for Large-Scale Wireless MANETs, [12] David B. Johnson; David A. Maltz., Dynamic Source Routing in Ad Hoc Wireless Networks. In Mobile Computing, edited by Tomasz Imielinski and Hank Korth, chapter 5, pages Kluwer Academic Publishers, [13] A. Qayyum, L. Viennot, and A. Laouiti. Multipoint relaying: An efficient technique for flooding in mobile wireless networks. Technical Report RR-2898, INIRIA, February 2. [14] Amir Qayyum. Analysis and Evaluation of Channel Access and Routing Protocols in Wireless LANs. PhD thesis, University de Paris-sud, Orsay, France, 2. [15] P. Jacquet, P. Miihlethaler, T. Clausen, A. Laouiti, A. Qayyum, L. Viennot. Optimized Link State Routing Protocol for Ad Hoc Networks. Page 29