Secure Threshold Sensitive Energy Efficient Sensor - Asee

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Sec-TEEN: Secure Threshold sensitive
Energy Efficient sensor Network protocol
Ibrahim Alkhori, Tamer Abukhalil & Abdel-shakour A. Abuznied
Department of Computer Science and Engineering
University of Bridgeport, Bridgeport, Connecticut
Introduction
Converting TEEN into SecTEEN
Wireless sensor Networks (WSN’s) as
illustrated in fig. 1, are composed of a huge
number of sensor nodes with limited energy
resources. Designing an energy efficient
protocol is a key issue that needs to be dealt
with in order to expand the life span of the
entire network. We propose to analyze the
performance of LEACH (Low Energy
Adaptive Clustering Hierarchy) as well the
TEEN (Threshold sensitive Energy Efficient
sensor Network) protocols. Further we discuss
the security features of SEC-LEACH and we
propose
adopting
the
authentication
mechanism of SEC-LEACH to the TEEN. We
show improvement by running experimental
testing with multiple rounds. The new
proposed SEC-TEEN improves the network
security in order to make it more robust to
external threats.
In our proposal, we used the security techniques
given by Sec-LEACH to design our secure
TEEN protocol. In other words, we propose to
generate a large pool of S keys and their ids prior
to network deployment. Each node is then
assigned a ring of m keys drawn from the pool
pseudo-randomly, without replacement.
The new TEEN algorithm can then be run with
the modifications described below. When a selfelected CH broadcasts its adv message, it
includes the ids of the keys in its key ring. The
remaining nodes now cluster around the closest
CH with whom they share a key. During the selfelection, CH broadcasts its id and a nonce. Then
each ordinary node in the network computes the
set of key ids, chooses the closest CH with whom
it shares a key, and sends a CH a join-req
message, protected by a MAC. The MAC is
generated, and includes the nonce from CH’s
broadcast to prevent replay attacks, as well as the
id r of the key chosen to protect this link (so that
the receiving CH knows which key to use to
verify the MAC). At the end of the setup phase,
the CHs send the time slot schedule to the nodes
that chose to join their clusters. In the steadystate phase, the CH broadcasts to its members
along with its adv message the values of hard
threshold and soft threshold.
Fig. 1. Four main parts for a typical WSN.
Simulation Model
Sec-LEACH vs. TEEN
When nodes communicate in a sensor network,
LEACH balances the draining of energy during
that communication. In a wireless sensor network,
LEACH rotates CHs randomly among all sensors
in the network in order to distribute the energy
consumption among all the sensors. LEACH
works in rounds. In each round, LEACH elects
CHs using a distributed algorithm and then
dynamically clusters the remaining sensors around
the
CHs.
Consequently,
Sensor-to-BS
communication takes place using this clustering
structure for the rest of the current round.
Secure Low Energy Adaptive Clustering
Hierarchy protocol (Sec-LEACH) is the same as
LEACH protocol but with some modification to
improve the level of security and to protect the
network from many kinds of attacks such as
sinkhole and selective forwarding attacks. SecLEACH randomly assigns each sensor with a ring
of keys taken from key pool pseudo that have
been generated at the time when the network is
deployed.
In TEEN routing protocol, nodes are arranged in
hierarchical clustering scheme in which some
nodes act as 1st level and 2nd level cluster heads.
After forming the cluster head, it gets the attribute
from the user. Once the attribute is received the
cluster head broadcasts the attribute. These are
hard and soft thresholds for sensed attributes
(values) to its cluster members. Hard threshold is
the minimum possible value of an attribute to
trigger a sensor node to switch on its transmitter
and transmit to the cluster head. The sensor nodes
start sensing and transmitting the sensed data
when it exceeds hard threshold. Nodes transmit
only when the sensed attribute is in the range of
their target. By doing that we are reducing the
number of transmissions significantly.
In terms of Data Overload, Sec-TEEN works with
extra conditions for sending data at each node, such
condition reduces the total transactions required in
the network communications. This leads to highly
reduced data overload compared with Sec-LEACH.
This trend can be exhibited by analyzing the
following graph;
Referring to Fig. 3 below and after applying both
algorithms on the network, we were able to achieve
better results in terms of energy saving. When
comparing the two protocols, we found that the SecTEEN performs much better than Sec-LEACH. SecTEEN has significant lower values of the energy
consumed by the nodes than what is consumed by the
Sec-LEACH. However, the two protocols have a
remarkably considerable variation in such values in
the case of energy saving.
Fig. 3. Total energy consumption occur in Sec-LEACH and
Sec-TEEN after 500 rounds, for network size (100).
Our experiment shows that the variation of energy
consumption is very significant for the simulation
network of 100 sensors. With a 0.5 Joule energy
initially given to each node in both protocols, we can
tell that nodes in the Sec-TEEN tend to consume
their energy at a slower rate if compared to the SecLEACH nodes.
Consequently, as can be seen from the Fig. 3, a WSN
of 100 nodes using Sec-TEEN have consumed all of
their energy at time 246. However, the nodes have
consumed the energy at time 224 for the SecLEACH. This improvement comes from the nature of
how Sec-TEEN works. Using the hard as well as soft
threshold values improved the performance of SecTEEN. Data are not sent when the sensed data do not
belong to the range of desired values which saves the
energy needed transmission. According to the energy
saving analysis, we can easily figure out that the
number of alive nodes at any point in Sec-TEEN will
be much higher than Sec-LEACH. This can be
depicted in Fig. 4, below; keeping in mind, the
number of alive nodes depends on the energy
consumption by the network.
Fig. 2. Total data overhead in Sec-LEACH and SecTEEN after 500 rounds for network size (100 nodes).
Our experiment shows that for the network of size
100 nodes, both Sec-LEACH and Sec-TEEN have
different volume of data being transmitted between
nodes to cluster heads and vice versa.
Referring to Fig. 2, we find that both of the SecLEACH and Sec-TEEN produce different total data
overhead in the specified network. From this point,
when it comes to our Sec-TEEN protocol, it
remarkably involves fewer amounts of data sent
between nodes in the system. It is noticed from
Figure 2 that after a period of time both protocols
will start having a steady phase in terms of data
overhead and that obviously is due to the energy
being completely consumed by all of the nodes. The
highest data volume sent by the Sec-TEEN was 1.76
x 107 bits where it was 3.1 x 107 bits in the case of
Sec-LEACH.
Fig. 4. Alive nodes in Sec-LEACH and Sec-TEEN after 500
rounds, for network size of 100 sensors.
Conclusion
We have proved using a simulation for WSN that SecTEEN has improved the network in terms of energy
consumption when compared to Sec-LEACH. This was
achieved by reducing the data overhead and reducing
the transmission of packets by having soft & hard
thresholds.
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