International Journal of Engineering Trends and Technology (IJETT) – Volume 7 Number 3- Jan 2014
A Protocol for Reducing Routing Overhead in
Mobile Ad Hoc Networks
Radhu.R.Nair#1
T. K Parani*2
#
Student, M.E Communication Systems engineering, Anna University
DSCE Coimbatore, India
*Assistant professor, dept. Electronics &Communication Engineering
DSCE Coimbatore, India
Abstract— Wireless networks offer more flexibility and adapt
easily to changes in the configuration of the network. A
decentralized type of wireless network is wireless Ad hoc
network. Mobile Ad Hoc Networks are a type of wireless Ad
hoc network that has a routing network environment. In
Mobile Ad Hoc Networks, each and every node can change its
locations and configure itself. Broadcasting is an effective
mechanism for route discovery in Mobile Ad hoc Networks, but
routing overhead associated with broadcasting can be large in
high dynamic networks.
A Neighbor coverage based
probabilistic rebroadcast protocol is used for reducing routing
overhead in Mobile Ad Hoc Networks. A novel rebroadcast
delay is used to determine the rebroadcast order, and it obtains
the more accurate additional coverage ratio by sensing
neighbor coverage knowledge. A connectivity factor is defined
to provide the node density adaptation for keeping the network
connectivity. By combining the additional coverage ratio and
connectivity factor, the rebroadcast probability is calculated
and is simulated using Network Simulator. This approach
significantly decreases the number of retransmissions so as to
reduce the routing overhead, and can also improve the routing
performance. Security against attacks and the shortest path to
destination will be incorporated in future for ensuring secure
routing in Mobile Ad hoc Networks.
Keywords--- Mobile Ad-Hoc Networks, broadcasting, neighbor
coverage, probabilistic rebroadcast, dynamic network, routing
overhead.
I. INTRODUCTION
Mobile Ad hoc Networks (MANETs) are selfconfiguring mobile wireless networks and that do not rely
on pre-existing infrastructure to communicate with other
nodes. A temporary network without the aid of any
infrastructure or centralized administration will be formed
by ad hoc networks which are a collection of wireless
mobile hosts. The structure of the network changes
dynamically in mobile ad hoc networks, which is a self
organizing and self-configuring multihop wireless
networks. It is because of the mobility of the nodes. To
engaging in multihop forwarding the nodes in these
networks utilizes same random access wireless channel,
cooperating in a friendly manner [5]. The node in the
mobile ad hoc network not only acts as hosts, it may be
intermediate hosts, source host or destination hosts but also
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as routers that helps to route data to/from other nodes in
network.
In mobile ad-hoc networks there is no
infrastructure support and there may be the destination
node might be in out of range of a source node, which
transmits the packets; so it is important that a routing
procedure is needed to find a path for forwarding the data
packets between the source and the destination. A base
station within a cell can reach all mobile nodes without
routing via broadcasting in common wireless networks.
Each node in ad hoc network must be able to forward data
to the other nodes. This creates additional problems with
dynamic topology which is unpredictable connectivity
changes.
Without a fixed infrastructure the mobile nodes in
MANETs can be dynamically self-organized into arbitrary
topology networks. Thus MANETs are suitable for
emergency situations like natural or human-induced
disasters, military conflicts, emergency medical situations,
etc because of its random topology. Using random
mobility model, the nodes in Mobile Ad hoc Network can
get the service to communicate each node in network [5]
Due to high mobility in network, there is no base station
service to network and routing path cannot be define
constantly for data transmission, so data loss and path
failure is the major issues in Mobile Ad Hoc Networks.
By comparing with wireless networks, the Mobile
Ad-Hoc Networks has no infrastructure support and since
a destination node might be out of range of a source node
transmitting packets so a routing procedure is necessary to
find a path to forward the packets between the source and
the destination nodes. Dynamic routing mechanism leads
to improper neighbor selection and flooding of route
request (RREQ) packets to reach destination. Each node in
mobile ad hoc network is willing to forward data from a
source node to other nodes. Broadcasting of route request
packets is a fundamental and efficient data forwarding
mechanism for route discovery.
Data broadcasting has many advantages and
also it causes some problems such as the broadcast storm
problem. The redundant retransmission, collision and
contention are collectively known as broadcast storm
problem. Flooding is the simplest mechanism in mobile ad
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International Journal of Engineering Trends and Technology (IJETT) – Volume 7 Number 3- Jan 2014
hoc networks for broadcasting and it leads to broadcast
storm problem. The design of dynamic routing protocol
with good performance and less overhead is the main
challenges of MANETs. To discover a route, flooding
mechanism is adopted by the conventional on-demand
routing protocols. Ad hoc on-demand distance vector
routing (AODV) and dynamic source routing protocols
have been developed for Mobile Ad-Hoc Networks. The
scalability of MANETs is improved by these protocols and
it is done by limiting the routing overhead when a new
route is requested.
The traditional routing protocols in MANETs
send periodic messages to realize the changes in topology
of mobile ad hoc network. When compared to reactive
routing protocols, the Proactive routing protocols causes
high routing overhead and the broadcasting of messages
causes broadcast storm problem [7]. The neighbor
coverage method is better than other methods such as area
based, probability based, simple flooding methods In
neighbor coverage based probabilistic rebroadcast (NCPR)
protocol, rebroadcasting can be done with the help of
neighbor knowledge and probability to discover the route
better than broadcasting. A novel scheme called
rebroadcast delay to determine the rebroadcast order, and
then obtain the more accurate additional coverage ratio and
it is done by sensing neighbor coverage knowledge. The
coverage area concept is used to adjust the rebroadcast
probability of a node. The rebroadcast probability is
composed of two concepts. One is the additional coverage
ratio; it is the ratio of number of nodes that should be
covered by a single broadcast to the total number of
neighbors. The other is connectivity factor; it reflects the
relationship of network connectivity and number of
neighbors of given node [1].
The host is in dense area which means the
rebroadcast probability would be low when the numbers
of neighbor nodes are high. The host is in sparse area
which means the probability would be high when the
numbers of neighbor nodes are low. To keep the network
connectivity a connectivity factor is used and to reduce
the redundant retransmissions. Similarly the connectivity
factor is to determine how many neighbors should receive
the RREQ packet. The advantages of the neighbor
coverage knowledge and the probabilistic mechanism is
combined in this approach which can significantly
decrease the number of retransmissions thus the routing
overhead can be reduced, and can also improve the
routing performance.
II DRAWBACKS OF CONVENTIONAL PROTOCOLS
Nodes in wireless adhoc networks often change
their location within network. So, unnecessary routing
overhead is generated by some stale routes in the routing
table. The conventional on-demand routing protocols such
as Ad Hoc On-demand Distance Vector Routing protocol
(AODV) and dynamic probabilistic route discovery
protocol (DPR) uses flooding to discover a route. They
broadcast a Route request (RREQ) packet to the networks,
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and the broadcasting induces excessive redundant
retransmissions of RREQ packet.
To discover routes in Mobile Ad Hoc Networks
broadcasting of Route Request is used and it leads to a
considerable number of packet collisions, especially in
dense networks. The excessive redundant retransmissions
of route request packets are induced by broadcasting and
causes broadcast storm problem. The broadcast storm
problem is characterized by redundant retransmission,
collision and contention [9]. Frequent link breakages may
lead to frequent path failures and route discoveries. It is
due to node mobility in MANETs, which induces increased
the overhead in the network and reduces the packet
delivery ratio and increasing the end-to-end delay. There
are different protocols are introduced for reducing routing
overhead in mobile ad hoc networks. Gossip-Based Ad
Hoc Routing [6] is one of the protocol and In gossiping
approach each node forwards a message with some
probability, thus reduces overhead of the routing protocol.
If there is few neighbors in the network, there is a chance
that none of them will gossip. Thus the gossip will die.
III BLOCK DIAGRAM
Route
Recovery
Link
State
Network
Monitor
Route
Manager
Fig 1 Block diagram
IV BLOCK DIAGRAM DESCRIPTION
All nodes collect the data about neighbor nodes
initially. The networks monitor having the detailed
information of neighbor nodes such as Routing table. It
provides the connection information to Route manager.
The network monitor only provides the information about
nodes i.e., the node positions etc. Channel analyser
collects the detail about channel capability. If there is
channel fading, the channel analyser can get the
information about it. If there is any problem with link
channel then node will generate error message to inform
about failure. For route recovery the signal handoff is
done with the knowledge of route plan (RREP). The route
reply packets are used for this. The route manager informs
the channel fading. The link state provides a connection
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or link between the network monitor, route manager and
route recovery. Thus information can easily monitor.
Route manager manages the reply route from destination
to source.
Broadcasting and Discarding of RREQ
Start
V FLOW CHART
Flowchart shows the initialization of the
processes like neighbor confirmation and calculation of
rebroadcast probability.
The node ni receive
duplicate RREQ from
other node nj
Start
If the timer
expires
No
If node ni
receive new
RREQ
Yes
Yes
Adjust uncovered
neighbor set
Compute
Rebroadcast
Probability Pre(ni)
Discard RREQ
Compute initial uncovered
neighbor set
No
If random
(0,1)≤
Pre(ni)
Calculate rebroadcast delay
Discard
RREQ
Set timer
Yes
Broadcast
RREQ
Stop
Stop
Fig 2 Flowchart for the calculation of rebroadcast delay
and uncovered neighbor set
Fig 3 Broadcasting and discarding of RREQ
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International Journal of Engineering Trends and Technology (IJETT) – Volume 7 Number 3- Jan 2014
VI
A.
MODULES DESCRIPTION
Route Discovery by RREQ
The route discovery from source to destination
is done by the RREQ packets. Initially all nodes collects
the data about neighbor nodes. Each node needs
information about its 1-hop neighbourhood. To estimate
how many its neighbors have not been covered by the
RREQ packet from s, when node n i receives an RREQ
packet from its previous node s, it can use the neighbor
list in the RREQ packet. It is referred from [1]. If node ni
has more number of neighbors which is uncovered by the
RREQ packet from s, which means that, the RREQ
packet can reach more additional neighbor nodes if node
ni rebroadcasts the RREQ packet. To calculate this, the
Uncovered Neighbors set U(n i) of node is defined. It is
given below:
Where Tp(ni) is the delay ratio of node ni, and MaxDelay
is a small constant delay. Its value is 0.01.∣.∣ is the
number of elements in a set. The rebroadcast delay is
defined with the following reasons: First, to determine
the node transmission order, the delay time is used. All
the neighbors of n i, i= 1; 2; ..., ∣N(s)∣ receive and process
the RREQ packet when node s sends an RREQ packet.
Consider that node n k has the largest number of common
neighbors with node s, according to (3). Then the node n k
has the lowest delay. Because of the largest number of
common neighbors of node n k, it will rebroadcast the
RREQ packet and there will be more nodes to receive it.
The main objective of rebroadcast delay is to disseminate
the neighbor coverage knowledge more quickly rather
than rebroadcast the RREQ packet to more nodes. The
node can set its own timer after determining the
rebroadcast delay.
D. Rebroadcast Probability Calculation
U(ni)=N(ni)-[N(ni)∩N(s)]-{s} ----(1)
Where N(s) and N (n i) are the neighbors sets of node s
and ni, respectively. s is the node which sends an RREQ
packet to node n i. According to equation (1), initial UCN
set is obtained. Due to broadcast characteristics of an
RREQ packet node n i can receive the duplicate RREQ
packets from its neighbors. With the neighbor knowledge
the node ni could further adjust the U(n i). The network
monitors having the detailed information of neighbor
nodes such as routing table. It provides the connection
information to Route manager.
B.
Failure Detection By ERR
The network monitor only provides the
information about node details. Channel analyser
collecting detail about channel capability. If there is any
problem with link channel then node will generate error
message for inform about failure.
C.
The RREQ packets from the nodes which
have lowered rebroadcast delay may listen to the node
which has a larger rebroadcast delay .For example, From
the neighbor set of n j, the node ni receives a duplicate
RREQ packet, it knows that how many its neighbors
have been covered by the RREQ packet from n j. Thus,
according to the neighbor list in the RREQ packet from
nj, the node ni could further adjust its UCN set [1]. Then,
the U(ni) can be adjusted as follows:
U(ni)=U(ni)-[U(ni)∩N(nj)] --------(4)
The RREQ packet received from node n j is discarded
after adjusting the U(n i). To determine the order of
disseminating neighbor coverage knowledge to the nodes
which receive the same RREQ packet from the upstream
node, the rebroadcast delay is used. Thus there is no need
to adjust the rebroadcast delay .The additional coverage
ratio of node n i is (Ra (ni)), which is defined as follows:
Ra (ni) = |U(ni)|
|N(ni)|
Rebroadcasting Delay Calculation
According to the neighbor list in the RREQ
packet and its own neighbor list, it could calculate the
rebroadcast delay when a neighbor receives an RREQ
packet. The key to success for the neighbor coverage
based probabilistic rebroadcast protocol is the choice of a
proper delay and it is because the dissemination of
neighbor coverage knowledge will be affected by the
scheme used to determine the delay time [1] . The
rebroadcast delay Td(ni) of node ni is defined as follows:
Tp (ni) = 1- | N(s)∩N(ni) |
|N(s)|
Td(ni) =MaxDelay
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--------(2)
--------(5)
This equation indicates the ratio of the number of nodes
that are additionally covered by this rebroadcast to the
total number of neighbors of node n i. There will be more
nodes which is covered by this rebroadcast as Ra
becomes bigger and more nodes need to receive and
process the RREQ packet. Thus, the rebroadcast
probability should be set to be higher. Assume the factor
Fc(ni), which is the ratio of the number of nodes that need
to receive the RREQ packet to the total number of
neighbors of node n i. To keep the probability of network
connectivity approaching 1, [10] a heuristic formula is
used:
Tp(ni) --------(3)
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∣N (ni)∣ . Fc (ni) ≥ 5.1774
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International Journal of Engineering Trends and Technology (IJETT) – Volume 7 Number 3- Jan 2014
Then define the minimum Fc (ni) as a connectivity factor,
which is given by:
Fc (ni) = Nc
|N(ni)|
--------(6)
Where Nc = 5:1774 log n, and n is the number of nodes
in the network. From the equation (6), it is observed that
Fc(ni) is less than 1, when ∣N(ni)∣ is greater than Nc. It
implies that node n i is in dense area of the network. Then
to keep the network connectivity only part of neighbors
of node ni forwarded the RREQ packet. And when ∣N(ni)∣
is less than Nc, Fc(ni) is greater than 1. It implies that the
node ni is in sparse area. The probability of the network
being connected is approaching 1 as n increases, if each
node connects to more than 5:1774 log n of its nearest
neighbors, where n is the number of nodes in the network
[10]. Then, the connectivity metric of the network is
used as 5:1774 log n. Combining the additional coverage
ratio and connectivity factor, we obtain the rebroadcast
probability Pre (ni) of node ni:
Pre (ni) = Fc (ni).Ra (ni) ------(7)
Where, set the Pre(ni) to 1,if the Pre (ni) is greater than 1,
The rebroadcast probability is defined with the following
reason. From the additional coverage ratio Ra, it can be
determine that how many neighbors should receive and
process the RREQ packet. The local node density
parameter is inversely proportional to Fc. The parameter
Fc increases the rebroadcast probability, if the local node
density is low. And then increases the reliability of the
Neighbor Coverage-based Probabilistic Rebroadcast
(NCPR) in the sparse area. The parameter Fc could
further decrease the rebroadcast probability, if the local
node density is high. And then further increases the
efficiency of NCPR in the dense area. The calculated
rebroadcast probability Pre (ni) may be greater than 1, but
it does not impact the behaviour of the protocol [1]. Then,
with probability Pre (ni), node ni need to rebroadcast the
RREQ packet received from s.
E. Route Recovery by RREQ and RREP
In this section the signal handoff is done with
the knowledge of route plan (RREP).The route manager
inform the channel fading.
VII PERFORMANCE ANALYSIS
To evaluate the performance of neighbor
coverage-based probabilistic rebroadcast protocol, it is
compared with some other protocols such as AODV and
DPR. It is simulated by using NS-2 simulator version 2.34.
A fundamental and effective data dissemination
mechanism for many applications in Mobile Ad Hoc
Networks is broadcasting. The Dynamic Probabilistic
Route Discovery protocol [2], which is an optimization
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scheme for reducing the overhead of RREQ packet in
route discovery and the conventional AODV protocol, is
chosen to compare the routing performance of the NCPR
protocol. Various performance parameters are evaluated.
MAC Collision Rate: It is defined as the average number
of packets (including RREQ, route reply (RREP), RERR,
and CBR data packets) dropped resulting from the
collisions at the MAC layer per second.
Normalized Routing Overhead: It is the ratio of the total
packet size of control packets (include RREQ, RREP,
RERR, and Hello) to the total packet size of data packets
delivered to the destinations.
Packet Delivery Ratio: It is the ratio of the number of
data packets successfully received by the Constant Bit
Rate (CBR) destinations to the number of data packets
generated by the CBR sources.
Average End-To-End Delay: It is the average delay of
successfully delivered Constant Bit Rate (CBR) packets
from source to destination node. It includes all possible
delays from the CBR sources to destinations. The
constant bit rate data traffic and randomly chosen
different source to destination connections.
F. Simulation Parameters
Table 1 simulation parameters
Simulation Parameter
Simulator
Topology Size
Number of Nodes
Transmission Range
Bandwidth
Interface Queue
Length
Traffic Type
Number of CBR
Connections
Packet Size
Packet Rate
Pause Time
Min Speed
Max Speed
VIII
Value
NS-2(v2.34)
1200 m 1200 m
350
250 m
3 Mbps
50
CBR
10,12,14,…..,20
512 bytes
4 packets/sec
0 sec
1 m/sec
5 m/sec
RESULTS
The sending of route request packet (RREQ) or
route to send packet (RTS) and acknowledgement (ACK) is
shown in NAM window in figure 4. The green circles show
the RREQ, ACK packets. The blue colour nodes indicate
the source and destination. The RREQ packet is send for the
route discovery from the source to destination.
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International Journal of Engineering Trends and Technology (IJETT) – Volume 7 Number 3- Jan 2014
Fig 6 MAC collision rate with varied number of nodes
Fig 4 Transmission of RREQ and ACK
The network animator window shows the
sending of data, route reply packets (RREP), route error
packet (RERR) in NAM window figure 5. The red color
indicates the TCP sending packets. The black circles
show the RREP and RERR.
The normalized routing overhead with varied
number of nodes is shown in figure 7. The RREQ traffic is
reduced as the NCPR protocol increases the packet size of
RREQ packets; it reduces the number of RREQ packets
more significantly.
Fig 7 Normalized Routing Overhead with Varied Number of Nodes
Fig 5 Transmission of data, RREP,RERR
G. Varied nodes with various performance metrics
The MAC collision rate with varied number of
node is shown in figure 6. The redundant rebroadcasting
mechanism is adopted by the conventional protocol such as
AODV.it introduces collision and interferences in the
network. These collisions leads to tremendous packet drops
that affects the packet delivery ratio. By above 92.8 percent
the collision will be reduced in NCPR protocol when
compare with AODV.when NCPR compare with DPR,the
collision rate in NCPR is reduced by above 61.6 percent
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Compared with the conventional AODV protocol,
the overhead is reduced by above 45.9 percent in the NCPR
protocol. the overhead is reduced by above 30.8 percent
when the NCPR protocol is compared with the DPR
protocol. When network is dense, the NCPR protocol
reduces overhead by above 74.9 percent and 49.1 percent
when compared with the AODV and DPR protocols,
respectively.
Average end to end delay with varied number of
nodes is shown in figure 8. The MAC collision rate of
conventional AODV is more severe. Thus the
retransmission increases. It incurs severe end to end delay.
NCPR reduces end to end delay by above 60.8 percent
when compared with AODV. when compared with DPR,
NCPR reduces delay by above 46.4 percent on average.
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International Journal of Engineering Trends and Technology (IJETT) – Volume 7 Number 3- Jan 2014
The normalized routing overhead with varied
CBR traffic is shown in figure 11.The overhead of the DPR
and NCPR protocols are relatively smooth, as the traffic load
increases, the routing overhead of the conventional AODV
protocol significantly increases. Both the DPR and NCPR
protocols reduce the routing overhead when comparing with
the AODV. When compared with AODV and DPR, The
NCPR reduces overhead by above 38.4 percent and 23.9
percent respectively.
Fig 8 Average end to end delay with varied number of nodes
The packet delivery ratio with varied number of
nodes is shown in figure 9. The MAC collision rate of AODV
is excess. So, it leads to packet drops. It reduces packet
delivery ratio. When AODV and DPR are compared with
NCPR, the packet delivery ratio of NCPR is increased by
above 11.9 percent and 3.7 percent respectively.
Fig 11 Normalized Routing Overhead with Varied Number of CBR
Connections
The packet delivery ratio with varied CBR
traffic rate is shown in thee figure 12. The packet delivery
ratio of AODV is reduced because of collision rate and
packet drop. When compare with AODV and DPR,the
NCPR has improved packet delivery ratio by above 11.5
and 1.1 percent respectively.
Fig 9 Packet delivery ratio with varied number of nodes
H. Varied CBR traffic
performance metrics
connections
with
various
The MAC collision rate with varied CBR traffic rate is
shown in the figure 10. As the CBR traffic rate increases,
it introduces increased collision rate, interference and
congestion. When compare with AODV and DPR
protocol, the NCPR protocol reduces the MAC collision
rate by above 95.2 and 69.2 percent respectively.
Fig 12 Packet Delivery Ratio with Varied Number of CBR
Connections
Fig 10 MAC Collision Rate with Varied Number of CBR Connections
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The average end to end delay with varied CBR
traffic rate is shown in figure 13. The redundant
retransmission increases with CBR traffic rate. Because as
traffic rate increases the packet drops will be severe. Thus
leads to enormous delay in the network. When compared
with AODV and DPR, the NCPR protocol reduces end to
end delay by above 71.0 and 28.9 percent respectively.
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International Journal of Engineering Trends and Technology (IJETT) – Volume 7 Number 3- Jan 2014
Fig 13 Average End- To- End Delay with Varied Number of CBR
Connection
I. Random packet loss rate with various performance
metrics
The MAC collision rate with random packet loss
rate is shown in figure 14. When uniformly distributed loss
rate from 0 to 0.1 is introduced in the network, AODV has
more collision rate with packet loss increases. When
compare with AODV and DPR, the NCPR protocol has
reduced collision rate by above 92.8 and 61.6 percent
respectively.
Fig 15 Normalized Routing Overhead with Varied
Random Packet Loss Rate
The packet delivery ratio with random packet loss
rate is shown in figure 16. By varying random packet loss
rate introduces packet drops in the network. When compared
with AODV and DPR protocols, the NCPR protocol
improves the packet delivery ratio by above 15.5 and 1.3
percent respectively
Fig 16 Packet Delivery Ratio with Varied Random Packet Loss Rate
Fig 14 MAC Collision Rate with Varied Random Packet Loss Rate
The average end to end delay with random packet loss
rate is shown in figure 17. By above 53.9 percent NCPR
reduces end to end delay when it is compared with AODV.
But the delay is increased by 0.6 percent when it is
compared with DPR protocol under the same conditions.
The normalized overhead with random packet
loss rate is shown in figure 15. There will be more link
breakages and route discoveries, and then there will be
more routing overhead as the packet loss increases. Both
the DPR and NCPR protocols introduces less routing
overhead than the conventional AODV. When compare
with AODV and DPR, the NCPR has reduced overhead by
above 59.4 and 22.3 percent respectively.
Fig 17 Average End-To-End Delay with Varied Random Packet Loss
Rate
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International Journal of Engineering Trends and Technology (IJETT) – Volume 7 Number 3- Jan 2014
IX CONCLUSIONS
The neighbor coverage-based probabilistic
rebroadcast protocol reduces routing overhead in Mobile
Ad-Hoc Networks. Apart from conventional routing
protocol, it eliminates broadcast storm problem and the
rebroadcasting of RREQ and RREP packets in the
network. In this protocol, the neighbor coverage
knowledge includes additional coverage ratio and
connectivity factor. A new scheme is used to dynamically
calculate the rebroadcast delay, which is used to
[[
determine the forwarding order. The rebroadcast delay
enables the information that the nodes have transmitted
the packet spread to more neighbors, thus more
effectively exploit the neighbor coverage knowledge. A
rebroadcast probability is introduced here, which can be
used to reduce the number of rebroadcasts of the RREQ
packet, to improve the routing performance. Simulation
results show that the neighbor coverage-based
probabilistic rebroadcast protocol generates less
rebroadcast traffic than the flooding and some other
optimized scheme in literatures. The simulation results
also show that the NCPR protocol has good performance
when the network is in high density or the traffic is in
heavy load. Security against attacks and shortest path to
destination can be incorporated as future work.
ACKNOWLEDGMENT
[3] AlAamri.H, Abolhasan.M, and Wysocki .T, (2009), ‘On
Optimizing Route Discovery in Absence of Previous
Route
Information in MANETs,’ Proc. IEEE Vehicular
Technology
Conf. (VTC), pp. 1-5.
[4] Chen .J, Lee Y. Z, Zhou. H, Gerla. M and Shu.Y
(2006), ‘Robust Ad Hoc Routing for Lossy Wireless
Environment,’ Proc. IEEE Conf. Military Comm.
(MILCOM’06), pp1-7
[5] En.wikipedia.org/wiki/mobile_adhoc network
[6] Haas. Z, Halpern. J. Y, and Li. L, (2002) ‘GossipBased Ad
Hoc Routing,’ Proc. IEEE Infocom, Vol. 21, pp.
1707-1716.
[7] https://datatracker.ietf.org/wg/manet/charter
[8] Johnson. D, Hu. Y, and Maltz .D, (2007), ‘The Dynamic
Source Routing Protocol for
Mobile Ad Hoc Networks
(DSR) for IPv4’, IETF RFC 4728, Vol. 15, pp. 153-181.
[9] Ni.S.Y, Tseng Y.C, Chen Y.S, and Sheu.J.P,(1999),
‘The Broadcast Storm Problem In a Mobile Ad
Hoc Network,’ Proc. ACM/IEEE MobiCom, pp.
151- 162.
[10] Zhang X.M, Wang E.B, Xia J.J, and Sung D.K,(2011) ,
‘An Estimated Distance Based Routing Protocol for
Mobile Ad Hoc Networks,’ IEEE Trans. Vehicula
Technology,Vol. 60, no. 7, pp. 3473-3484.
I, RADHU.R.NAIR, student of M.E COMMUNICATION
SYSTEMS, Dept. of ECE, Dhanalakshmi Srinivasan
College of Engineering, Coimbatore. I would like to thank
Asst. Prof. Ms.T.K..PARANI for her encouragement and
constant co-operation throughout the completion of the
paper. I deeply express my gratitude to all the ECE
department staffs for their valuable advice and co-operation.
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