Prevention of Denial-of-Service Attack In Wireless Sensor Network via NS-2

ISSN: 2312-7694
Shishupal et al, / International Journal of Computer and Communication System Engineering (IJCCSE), Vol. 2 (5), 2015, 708-715
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© IJCCSE All Rights Reserved Vol. 02 No.05 Oct 2015 www.ijccse.com
Prevention of Denial-of-Service Attack In
Wireless Sensor Network via NS-2
Shishupal Kumar Dr. Vijay Km Chaurasiya
Dept. of Wireless Communication and Computing Dept. of Wireless Communication and Computing
IIIT-Allahabad IIIT-Allahabad
India India
robincoolmasti@gmail.com vijayk@iiita.c.in
Abstract—A wireless sensor network encompasses many
number of sensor nodes which are used to observer the
conditions of physical environment surroundings like
temperature, pressure etc. They are very limited in power.
Sensor are used to carry sensed data from one location to another
desired location for further processing. They are very useful in
many application areas like agriculture, military, industrial
applications etc. However they are distributed in nature and
contains wireless characteristics. So it is obvious that they are
more vulnerable to security attacks just because of their wireless
nature and simple architecture. Security creates great impact on
the performance of any network. More secure network tends to
high performance of wireless network. In this paper, we propose
a method to prevent the denial of service attack which is one of
the most serious attack in the wireless nature network. The
proposed method provides some sort of prevention to the
network from the Denial of service attack. Also, we have used
some simulation results in order to compare the performance of
wireless sensor network without any prevention of denial of
service attack to the network of sensor nodes with exhibits the
proposed methodology. The results are simulated in terms of
throughput, packet delivery fraction and delay.
Index Terms— Wireless Sensor Network (WSN), Denial-of-
Service (DoS), NS-2, Mannasim
I. INTRODUCTION
In the evolution of 1970’s, some sensors deployed which
are wired in nature and connected to any central location.
After, in 1980’s, sensors had been deployed which are wireless
in nature and contained distributed property. First, use of
Wireless sensors in military applications to sense the detection
of enemy. Now wireless sensor network reaches in the peak
level of industrial applications and as well as a research area.
[1] The nodes in wireless sensor network comprise of trivial
components like batteries, microcontroller, limited memory,
etc. They have very limited processing capability because of
partial power and memory. The properties of the sensor nodes
are, they cope with node failure very rapidly, they can work in
severe environmental conditions, they support a very high
number of nodes, and they efficiently support high mobility.
[2] The task performed by the nodes of sensor network
environment is very time sensitive i.e. at the exact time the data
should reach to the end user so that further processing will take
place. [3] Wireless sensor network consists of nodes which are
designed to perform specific functions and all the nodes in the
network perform the function altogether. [4] The basic function
of the sensor nodes in the wireless sensor network to sense the
data and to record it and sends this recorded data to particular
destination when event of specific conditions occurs. [5] The
hardware of the wireless sensor network are very small and can
transfer data at very low energies which basically makes
different to nodes in wireless sensor network from other
wireless network nodes. A simple structural layout of sensor
nodes in a wireless network is presented in the below figure.
Fig 1: The simple architecture of Wireless sensor network

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In a wireless sensor network, after sensing and recording
the data whenever a particular condition occur, the recorded
data is sent by the particular sender sensor node to the end user.
So for transmitting the data from one location to another
location definitely, a routing protocol is necessary. [6] The
routing protocol should be in such a way that it has to consume
very minimum energy and also have very minimum capability
i.e. not as much of overhead, for the reason that sensor nodes
have precise limited power and processing competency. The
protocols used in wireless sensor network for routing of data
from source node to destination node are AODV, DSDV etc.
The nodes of the wireless sensor network are distributed in
nature and because of their wireless nature they are always
vulnerable to security attacks. Security is one of the major
parameters which can directly impact on the performance of
the network. [7]There are various types of security attacks
possible in the wireless sensor network like flooding attack,
wormhole attack, denial of service attack, sinkhole attack, and
Sybil attack. [8]For enhancing the security of the sensor
network some cryptographic techniques can be used like key
exchange algorithm, [9]which provides authenticity,
availability etc. [10] an Extra remote home server (RHS) can
also be installed which take care of any illegal activity of all
the sensor node and can work as an administrator of the
wireless sensor network. [11] But the key goal should be to
propose a mechanism which takes very minimum energy
consumption and also provides some prevention from the any
kind of security attack. [12, 13, 14] A framework is proposed
for estimation of secure location of sensor nodes for various
WSN applications because of prevention from any
unauthorized access. [15, 16] Providing security in the network
of sensor node is very difficult as compared to mobile ad hoc
network because the nodes in wireless sensor network are
limited in power and processing. [17] For further enhancing
security, a distributed scheme is proposed which provides
security from replay attack in sensor network and this scheme
is called RED protocol. [18] For the handling of node failures,
also there are various protocols introduce like Tiny IDS. [19]
Bluetooth technology can also be used for providing security in
Wireless sensor network. [20] In a sensor network , a sensor
node sends data and sends to the base station and during this
process a secure communication and reliability is required
which can be provided by using the Hybrid Multipath Scheme.
[21] An entropy-based trust model is used for detection of
malicious nodes in environment of wireless sensor network.
[25] To cop up the link failures various types of data gathering
methods can be used which inherits colouring algorithm in
wireless sensor network called as SERENA. In this algorithm
each colour is allotted a unique time slot. [26] A new
technology is proposed whose name is ANT for wireless sensor
network which is widely uses the mac layer protocol and
specially developed for sports concerning sensor devices. Its
main focus on the proper optimization of bandwidth of the
network and low consumption of power. [27] To maintain the
continuous service and connectivity some strategy can be
followed like the Centralized Maintenance Strategy (CMS) and
the Centralized Maintenance Strategy with Anticipation
(CMSA). These strategy contains a small number of mobile
like robots which looks after the network of sensor nodes and
reports timely regarding failure, connectivity loss, coverage
problem etc. [28] a multi tree based approach can be used in
wireless sensor network which ensures that at least one node
can connect to the communication network when network
failure occurs. [29] Automatic firing practice system (AFPS)
can be used for special operations force, tactical paramilitary
and Law Enforcement Agencies. This implemented firing
system is very flexible and contain small alarms and supports
various mode of firing.
In this paper, our main focus is in denial of service attack
because this is considered as one of the most dangerous and
serious attack in the network environment. In the next, Section
2 will describe about denial of service (DOS) attack. Section 3
will contain the related work about proposed method. Section 4
will contain simulation parameters in tabulated form and at
last, Section 5 will contain results and comparison of wireless
sensor network without prevention to the wireless sensor
network under prevention from denial of service attack.
II. DENIAL OF SERVICE (DOS) ATTACK IN SENSOR
NODES OF WIRELESS NEYWORK
Wherever Denial of service attack is one of the harmful
attack for the network because in Denial of service attack
(DOS), [22] whenever a sensor node have data to send, it
forwards data to its neighbouring node which is in its
communication range and if this neighbouring node is working
as a malicious node then it does not forward data even creates
overloading request for data to the sender node and consumes
all its bandwidth. Sensor nodes in the wireless sensor network
have limited in power so the node will eventually die by this
type of attack as well as Denial of service attack also enlarge
the delay time by consumption of processor time and
bandwidth. It creates alternation in the content of data and
disturb the activity of the routing protocol by disruption of
routing information. It distorts the activity of the physical
components of the sensor nodes as well as it creates an
obstruction between the communication between the sender
and intended receiver. [23, 24] It aims to target on applications
of physical layer where the sensor nodes are located. DOS
attacks make the sensor node dies very rapidly because they
have already scarcity of limited computational power and
processing capability. In a wireless sensor network, every
sensor node is intended to perform a particular sensing tasks
and in the presence of malicious node there may be an event of
sending wrong information to the base station also happen. To
make the network under DOS the malicious node take two
ways to implement this attack. The first one is jamming and the
second one is power exhaustion. In this paper, we are

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discussing only DOS attack related to the network layer in
which malicious node drops all the data forward from the
source node and create network flooding by sending dummy
packets. The main focus is to prevent power exhaustion of
sensor nodes in the network because they are very limited in
energy resources. This type of DOS attack aims to disturb
sleep/duty cycles of sensor node continuously and results the
network of sensor node will die very soon. Denial of service
attack rapidly decrease the performance of overall wireless
sensor network and directly does bad impact on the
functionality of the sensor nodes.
In the below figure 2, wireless sensor network below DOS
attack is described in a practical manner and simulated in NS-2
environment. In this scenario, node 18 act as a base station.
Node 7, 8, 12, 14 act as a malicious node have aimed to
degrade the performance of the WSN environment. Node 17
and 19 act as a source node and their task is to forward data to
the base station by using AODV protocol. So for initiating the
communication between source node 19 and node 18 which act
as a base station, source node 19 communicates with their
neighbourhood sensor node, i.e. node 8 and this node 8 acts as
a malicious node in this scenario. The main focus of the
malicious node is to get attention from the source node so that
it always advertises itself with a higher sequence number with
minimum hope count. When source node 19 starts forwarding
data to the node 8 then malicious node 8 drops all the packets
so that the performance of wireless sensor network degrades
very rapidly. For making the system under into DOS attack,
these malicious node flood dummy data all over the network
with aim of consumption of power of sensor nodes in WSN by
disrupting their sleep or duty cycle. Eventually the power of
sensor nodes degrades very rapidly result nodes will die very
soon and the whole system of wireless sensor network will be
under DOS attack.
Fig 2: Wireless sensor network with AODV routing protocol under DOS
attack
II. PROPOSED METHOD
The In this paper, we are introducing a method which provides
prevention to the network from the denial of service attack.
The nodes in the wireless sensor network use very simple and
suitable routing protocol for routing of data from sender to the
corresponding receiver. This property makes the wireless
sensor network simple as well as lying to network security
attack. Besides this, complex algorithms and techniques
consumes lot of processing and computation power of the
nodes in wireless sensor network and there is already a scarcity
of these resources. So in this paper, a simple method is
introduced which takes prevention before sending a packet to
their neighbouring node. A sending node whenever have data
to send, it senses the neighbouring node which in its range of
transmission and communication. Before sending the data to its
intended neighbouring nodes, it first checks for the historical
throughput which is basically the value of the forwarded
number of packets. The value of this historical throughput is
stored in a variable. Whenever a node wants to send data, it
authenticates its neighbouring node’s historical throughput
value, whenever the value of this historical throughput variable
is equal to 0 or exceed over the predefined threshold than that
neighbouring node is suspected to be improper node and mark
this neighbouring node as a malicious sensor node. After this
step, the sending node again starts sensing another new
neighbouring node to send the data to the intended receiver.
For making a differentiation between the malicious node and
valid sensor node, it periodically flushes the value of historical
throughput of valid sensor node when its value becomes equal
to the predefine threshold value. So the value of historical
throughput of the valid sensor node will always lie between
greater than 0 and less than a predefined threshold. Below
figure 3 represents the flowchart for proposed methodology.

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Fig 3: Flowchart for proposed method
In the above flowchart, H[Th] represents the historical
throughput of the node. N.H[th] represents the historical
throughput of the neighbouring node which is sense by the
corresponding sender node and C.H[th] denoted historical
throughput of the current working node. Historical throughput
basically is the number of packets sent with respect to the time.
The procedure of the above mentioned flowchart can be well
understand by the following points:
• Whenever a Sender node wants to send data then it
first senses one of its neighbouring node. Before sending data
to its neighbourhood sensor node it first authorizes it to ensure
that it is not a malicious node to provide some protection to the
system from denial of service attack or any kind of security
attack. It does so by comparison of historical throughput of
neighbouring node.
• If historical throughput of neighbouring node is
greater than the predefined threshold value or equal to 0 then it
indicated that is working as a malicious node and sender node
will not send data packet to that node and will mark this node
as malicious node with again senses the another neighbourhood
node with in transmission range and again the procedure Will
applied. Below figure 4 shows above describe scenario:
Fig 4: An example of sensor network which describe above mentioned
procedure
In figure 4, green circle represents sender and receiver
sensor nodes while red circle represents malicious sensor node
and besides theses, all circles are remaining nodes of the sensor
network.
• If historical throughput of neighbourhood node is less
than the predefined threshold and also does not equal to 0 then
sender node will send data to this neighbourhood node. In this
scenario, if historical throughput of the current node becomes
equal to its predefined threshold then it flushes its H[th] values
and make it equal to 0 and after that it updated it by H[th] =
H[th] + 0.1. This step is due to maintain the proper
differentiation between the valid and malicious node. In this
way, the value of H[th] of every sensor node in the network
will between 0 and predefined threshold.
Fig 5: A wireless sensor network which shows above mentioned procedure

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III. SIMULATION PARAMETERS
In this paper, the proposed method of prevention from denial
of service attacks is simulated in network simulator (NS-2).
NS-2 is used for simulation of wired or wireless networking,
for the simulation of wireless sensor network an Extra
component is added in the NS-2 simulator which is called
Mannasim. Mannasim is a software which enables easy
simulation of wireless sensor network. The simulation
parameters for our proposed method is tabulated below:
Table I: simulation parameters of proposed methodology
Sr No Parameter Value
1 Simulator NS-2(Mannasim)
2 Channel type Channel/Wireless
channel
3 Radio Propagation Propagation/ Two ray
Model
ground wave
4 Network interface type Phy/WirelessPhy
5 MAC Type Mac /802.11
6 Frequency 914e+6
7 Routing Protocol AODV
8 Antenna Antenna/Omni Antenna
9 Initial energy 10
10 Area ( M*M) 500 * 500
11 Simulation Time 250 sec
12 No of Nodes 50
13 rxPower 0.5
14 txPower 1.0
15 idlePower 0.0
16 sensePower 0.3
17 CPThresh_ 10.0
18 sensing 2.28289e-11
range_CSThresh_
19 communication 2.28289e-11
range_RXThresh_
IV. RESULTS AND COMPARISON
The simulation of proposed wireless sensor network
environment is done in network simulator with Mannasim
software. The simulation results are evaluated in terms of
throughput, Packet delivery ratio and end-to-end delay. In this
paper, we compare the performance of a network of sensor
nodes under the prevention of the proposed methodology with
the network of sensor node without prevention from denial of
service attack. This result will evaluate the impact of the
proposed methodology to the wireless sensor network.
A: THROUGHPUT
The principal performance is measured in the relations of the
throughput. Throughput is represented in bits per second (bps)
and it is the number of packets which is received in per unit of
time. Figure 3 represents the throughput of the wireless sensor
network environment under no prevention
Fig 3: Throughput of wireless sensor network without prevention
In the above figure, it is shown that the Throughput of the
simulated wireless sensor network comes out to be about
1179.25 kbps. Figure 4 represents the throughput of the
proposed methodology in wireless sensor network.

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Fig 4: Throughput of the proposed method for wireless sensor network
In the above figure, the Average throughput is evaluated in
terms of Kbps and that comes out to be about 1305.71Kbps
which is much higher than the throughput from the sensor
network under without any prevention of security attacks.
B: PACKET DELIVERY RATIO/FRACTION
Packet delivery ratio (PDR) is the fraction concerning the
data Packets received by the destination for those sent by
sources. This evaluates the ability of the protocol performance
and its efficiency. Figure 5 represents the Packet delivery ratio
of wireless sensor network under no prevention.
Fig 5: packet loss in the simulated sensor node network without proposed
method
In the above figure, it is clearly shown that is number of
sending packets are 105266 and the number of received
packets are only 77753, so the total number of packets which
are lost are about 105266 – 77753=>27513 which is very high
and does harmful impact for network of sensor nodes.
Fig 6: Packet delivery ration of simulated wireless sensor network
In the above figure, It is clearly seen that the total number
of sent packets is 71574 and total number of receiving packets

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are 71572 i.e. the number of packets which are less in the
simulated environment are only 2, which is very less and hence
it leads to high performance of the wireless sensor network.
C: END-TO-END DELAY
End to end delay is the quantity of the time which is
occupied to sending packets from source to their respective
destination to receive those packets. More delay can lead to
low performance of the wireless sensor network and low delay
is the indication of high efficiency and speed of the network.
Figure 6 represents the end-to-end delay of the wireless sensor
network without taking any prevention.
Fig 7: End-to-end delay of wireless sensor network without any prevention
method
“
Fig 8: End-to-end delay of simulated wireless sensor network with proposed
method
CONCLUSION
Wireless sensor network is becoming very famous now
days in the field of various industrial and research
environments. They support a very large number of nodes up to
thousands and also support a high degree of mobility. The main
functionality of the sensor node to sense a particular data and
to store in its limited available memory and by occurring on
particular event they must send their sensed data to the
corresponding end user. However, in the network environment,
especially in the area of wireless, the nodes are distributed in
nature and they lead high chance of getting attacked by intruder
which badly decrease the performance of the network and let
the sensor node die of consumption of its computing and power
resources. As well as sensor node is like very small nodes
which have smaller components and the use of very complex
techniques for providing security leads to the sensor node dies
very soon and enlargement of delay. In this paper, a simple
methodology is proposed which takes very little computational
power and does not impact on the battery consumption of
sensor nodes as well as it offers some sort of authentication of
nodes so that network will at all times inhibit from any denial
of service attack (DOS).
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Prevention of Denial-of-Service Attack In Wireless Sensor Network via NS-2