26-12-2012, 03:20 PM
PERFORMANCE ANALYSIS OF ADHOC ROUTING PROTOCOLS USING
RANDOM WAYPOINT MOBILITY MODEL IN WIRELESS SENSOR NETWORKS
PERFORMANCE ANALYSIS.pdf (Size: 143.49 KB / Downloads: 43)
Abstract:
This paper investigates and undertakes simulation based study of adhoc routing protocols in wireless sensor
networks. In this paper we have compared the performance of two routing protocol AODV and DSR by using
random waypoint mobility model and changing the node density with varying number of source node. DSR and
AODV both protocol use On-Demand route discovery concept but internal mechanism which they use to find
the route is significantly different for both protocol. We have analyzed the performance of protocols for varying
network load and mobility. Simulation with random waypoint mobility model has been carried out by using
qualnet 5.0.2 Simulator. The metrics used for performance evaluation are packet Delivery fraction, Average
end-to-end Delay, Average jitter.
Introduction
Wireless Sensor Networks (WSN) is a special class of ad hoc wireless network that are used to provide a wireless
communication infrastructure that allows us to instrument, observe and respond to phenomena in the natural
environment and in our physical and cyber infrastructure. Even though sensor networks are a superset of ad hoc
routing protocols, the routing protocols proposed for ad hoc routing protocols cannot be used as it is for sensor
networks because of various reasons as given in [1, 2]. But Surprisingly we found out that there is lack of
simulation based study or research work [7] as to show why ad hoc routing protocols cannot be used in a sensor ad hoc routing protocols to understand their behavior when used in a sensor network environment.
This paper is organized as follows. In the second section 2 we discus the random Waypoint Mobility Model. In
section 3, we give brief introduction of AODV and DSR [8] routing protocol and in section 4 deals the simulation
setup and results obtained on the execution of simulation. Finally we draw the conclusion in section 5.
Random Waypoint Mobility Model :
Random waypoint model is a random based monility model used in mobility management schemes for monile
communication systems. This designed to describe the movement pattern of monile user which include how their
location, mobility and accelaration change over time. The random waypoint model, first proposed by Johnson and
Maltz [11], soon became a “benchmark” mobility model to envaluate the because of its simplicity and wide
availability.
Dynamic Source Routing (DSR)
Dynamic source routing protocol (DSR) [4]: DSR is an on-demand routing protocol. The major difference
between DSR and the other on demand routing protocols is that, it is beacon less and hence does not require
periodic hello packets. Consider a source node that does not have a route to the destination. When it has a data
packet to be sent to that destination, then it initiates a RouteRequest packet. This RouteRequest is flooded
throughout the network. Each node upon receiving a RouteRequest broadcasts the packet to its neighbors if it
has not forwarded already or if the node is not the destination node. Each RouteRequest carries a sequence
number generated by the source node and the path it as traversed. A node, upon receiving a RouteRequest
packet, checks the sequence number on the packet before forwarding it. The packet is forwarded only if it is not
a duplicate Route Request packet. The sequence number on the packet is used to prevent loop formations and to
avoid multiple transmissions of the same RouteRequest by an intermediate node, which receives it through
multiple paths. Thus, all the nodes except the destination node, forwards a RouteRequest packet during the route
construction phase. A destination node upon receiving the RouteRequest packet, replies to the source node
through the reverse path the RouteRequest packet had traversed. Several optimization techniques have been
incorporated into the basic DSR protocol to improve the performance of the protocol like caching the routes at
intermediate nodes. The route cache is populated with the routes that can be extracted to forward the data
packet. This cache information is used by the intermediate nodes to reply to the source when they receive a
RouteRequest packet and if they have a route to the corresponding destination.
Packet delivery ratio:
In case of low traffic ( 5 to 15 source nodes) with low node density (50 nodes) AODV protocols delivers almost
all originated data packets (around 90-100%) But the packet delivery fraction starts degrading gradually when
there is increase in number of sources node. DSR perform less efficiently then AODV when number of source
nodes are low( 5 to 15 source nodes) with low node density (50 nodes) But when network load increases packet
delivery ratio of DSR degraded faster as compare to AODV (fig 1). For high node density (100 node) and low
traffic ( 5 to 15 source nodes) AOVD perform better then DSR but once traffic is increase ADOV performance
decrease drastically (we can see in case of 20 source nodes ) and DSR start performing better then AODV (fig
1).
Average End to End delay:
Figure 3 show that average end to end delay is low (below 10 second) in case of AODV protocol for both high
node Density (100 node) and low node Density (50 nodes). AODV user only one route that is shortest path for
delivery data from source node to destination node due to this reason average end to end delay for AODV is low
as compare to DSR. DSR use more then one route to transfer data packet from source node to destination node
which causes more delay as it is not always using shortest path for delivering all data packet from source node
to destination node.
Conclusion
From the figure 1 to 3, we obtain some conclusion that in Random waypoint mobility model with CBR traffic
sources, AODV perform better than DSR when node density is low. In case of high node density AODV
performance is still better in low Traffic load. But in case of high node density and high traffic load DSR
perform better than AODV. AODV always give low jitter irrespective of traffic load and node density also
AODV gives better performance then DSR for Average End to End delay. Average End to end delay for DSR
increases rapidly when traffic load increases and it is not affected by the node density.
In this paper, only two routing protocol are used and their performance have been analyzed under random
waypoint mobility model. Also we list the various problems we had to face while simulating the routin protocols
in a sensor network paradigm. Our future work includes designing an energy efficient routing protocol for
Wireless Sensor Networks. With all these research challenges we firmly believe that we have a very exciting
time ahead of us in the area of Wireless Sensor Networks.