Comparative analysis of AODV and DSDV routing protocols for Mobile Ad Hoc Networks

Mobile Ad hoc Networks (MANETs) are collection of wireless mobile nodes. MANETs are infrastructure less temporary networks. They do not have fixed static infrastructure. As no fixed infrastructure is available all nodes itself, work as receiver, transmitte as well as router. These nodes are also mobile so providing stable route is a big challenge. We have different approaches to find route in MANETs and all approaches use some protocols. This paper concentrates upon the analysis of two Mobile Ad Hoc Networking protocols. Ad hoc On demand Distance Vector (AODV) and Destination-Sequenced Distance Vector (DSDV). DSDV uses proactive or table driven approach to route the data whereas AODV is a reactive protocol and uses on demand routing. Main target of this paper is to highlight different aspect of both protocols and compare them. So, one can decide which protocol is better suited to their needs.


International Journal of Trend in Scientific
Research and Development (IJTSRD)

International Open Access Journal
Comparative analysis of AODV and DSDV routing protocols for Mobile Ad Hoc Networks Anurag Misra Training Specialist, HIPF, Riyadh Mobile Ad hoc Networks (MANETs) are collection of wireless mobile nodes. MANETs are infrastructure less temporary networks. They do not have fixed static infrastructure. As no fixed infrastructure is available all nodes itself, work as receiver, transmitter as well as router. These nodes are also mobile so providing stable route is a big challenge. We have different approaches to find route in MANETs and all approaches use some protocols. This paper concentrates upon the analysis of two Mobile Ad Hoc king protocols. Ad hoc On demand Distance-Sequenced Distance-Vector (DSDV). DSDV uses proactive or table driven approach to route the data whereas AODV is a reactive protocol and uses on demand routing. Main er is to highlight different aspect of both protocols and compare them. So, one can decide which protocol is better suited to their needs.

INTRODUCTION
Mobile Ad hoc Network (MANET) is a collecti nodes which all can communicate without any fixed infrastructure, over a wireless medium. All the nodes work as hosts as well as router. And all of them are mobile. Nodes can directly communicate with each other or they can use other intermediate nod forward data from source to destination. In MANETs almost everything is changeable including number of nodes, speed, topology etc. As MANETs are made up of independent nodes and nothing is fixed in MANETs. So, networks have to be self configurable. With so many constraints like limited bandwidth, speed and energy developing protocols for MANETs is a great challenge. There are three main approaches to develop routing protocols for MANETs and those are shown below in figure 1.  Table contains latest information about routes and cost of routes to reach a particular destination. When any change in the topology occurs or any new node is added route update information is sent to all the nodes by broadcasting. These protocols are not able to perform well if network topology changes very frequently or if network has too many nodes because of too much routing overheads. Some of the proactive protocols are Destination Sequenced Distance Vector (DSDV) and Optimized Link State Routing (OLSR). In this paper our main concern will be DSDV for our study.

Destination Sequenced Distance Vector (DSDV)
Destination Sequenced Distance Vector (DSDV) is proactive Here, Sn and Se are the sequence numbers of new message and existing message respectively.

Reactive (On Demand) Routing Protocol
Reactive Routing Protocols don't keep permanent routing tables and don't react on any changes in topology or on addition of a new node. These protocols search for a route only when some node attempts to send data over the network. When a node attempts to send data, it request for a route and then only these protocols searches for a route by flooding the route request packets throughout the network. Some of the reactive routing protocols are Ad hoc On demand Distance Vector (AODV) and Temporarily Ordered Routing Algorithm (TORA). In this paper our main concern will be AODV for our study.  Table 1 shows the comparison of both of the protocols. But this comparison is still quite theoretical. Although it's such a descriptive and elaborate theoretical comparison that, one can easily decide which type of protocol from AODV and DSDV is best suited to their needs but still its good idea to come up with a firm practical data to compare the actual performance of both the protocols. That can be quite ensuring than just the comparative theoretical analysis. That's why now we will have some simulated data for both of the protocol to show how they perform in simulated conditions and parameters.

Random Way Point model
Random Way Point model is used for this simulation. This model is first proposed by Johnson and Maltz.
And it became a benchmark to evaluate MANET routing protocols due to its simplicity and wide availability. RWP model is a random model for mobile users and how their location, acceleration and velocity change over time. In RWP model initially, all the nodes are distributed randomly over the simulation area. Node selects its random destination among the other nodes with in simulation area. After selection of this random destination, velocity is chosen from a uniform distribution. After reaching destination node, a small "pause time" is given and then again next random destination is selected by MN. MN also chooses a speed uniformly distributed between minimum to maximum speed. To reflect the degree of mobility some parameters could be set for value of travelling speed which is chosen uniformly in the interval. At this selected speed, MN continues its journey towards newly selected destination. After reaching on destination again the whole process is repeated after pause time.

Simulation analysis and results
For this study topology of fixed area of 700 x 700 m 2 is used with varying number of nodes 25, 50, 75, 100. Speed used is 20 ± 3 m/s, pause time is 15 ± 3 s, packet size is 512 B, simulation time is 300 s and traffic node is 10, 20, 40, 60 respectively with 25, 50, 75, 100 nodes in simulation. We consider effect of mobility on 4 major factors. These are Packet Delivery Ratio, Average End to End Delay, Normalized Routing Overheads and Throughput of the MANET.

Packet Delivery Ratio
Packet Delivery Ratio is the ratio of total number of packets successfully received by the destination nodes to the number of packets sent by the source nodes throughout the simulation. It also describes the loss rate of the packets, which affects the maximum throughput that can be supported by the network.

Throughput
Throughput is the average rate at which the total number of data packets are delivered successfully from one node to another over a network. Measuring unit for throughput is KB/Sec and formula by which throughput is calculated is as follows:

Conclusion
In this paper, we have tried to analyze two routing protocols which both are used for MANETs. And both of them are using different approaches for routing. DSDV is a proactive table driven protocol whereas AODV is reactive on demand protocol. We have compared both of them for Packet Delivery Ratio, Average End to End Delay, Normalized Routing Load and Throughput. Random Waypoint model is used for the simulation by which this data is collected. As per results it is very clear that increasing number of nodes affects both the protocols to a very great extent. But still it affects DSDV more than AODV. DSDV is not bad for lesser number of nodes but when number of nodes increase from 100 or above performance of DSDV decreases drastically. But although AODV performance also decreases when number of nodes are increased but still it performs much better. Only for Normalized Routing Load DSDV's and AODV's performance is quite comparable. But for Packet Delivery Ratio, Average end to end delay and Throughput, AODV clearly outperforms DSDV, especially for greater number of nodes.