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that change, which is extremely resource-consuming and
will result in the unnecessary usage of bandwidth even
when no data is transferred. Another drawback is more
power consumption due to periodic exchange of
information. Examples of such protocols are Destination-
Sequenced Distance-Vector Routing protocol (DSDV),
Optimized Link State Routing (OLSR), Cluster head
Gateway Switch Routing (CGSR) protocol, The Wireless
Routing Protocol (WRP).
1.1.4 On-demand routing protocols
Reactive routing protocols find a route only when there
is a demand for data transmission, i.e., at the beginning of a
connection. In other words, the route discovery process
begins whenever a source node needs a route to a
destination in on-demand routing. A route between two
hosts is determined only when there is an explicit need to
forward packets. This is done by initiating a route
discovery within the network by flooding the entire
network with route request (RREQ) packets. Also, once a
route is established, it is maintained in the routing table
until the destination is out overhead is significantly reduced,
since the routing information does not have to be updated
periodically, and no maintenance is done on routes that are
not being used. One disadvantage of these protocols is the
latency that occurs when a route is required. However, for
highly mobile networks, these protocols show better
performance for MANETs. Few examples of such
protocols are Ad Hoc On-Demand Distance Vector
(AODV) routing protocol, Dynamic Source Routing (DSR)
protocol, Temporally Ordered Routing Algorithm (TORA)
and Associativity-Based Routing (ABR).
1.1.5 Hybrid routing protocols
On-demand routing has relatively less routing overhead,
since it eliminates periodic flooding of the network with
update messages. But it suffers high routing delay when
compared to table-driven routing. Table driven routing
ensures high quality in static topologies but cannot be
extended to mobile networks. Combining the advantages of
both, a few hybrid routing protocols have been designed,
whereby the routing is first initiated with some proactive
routes and then serves the demand from other nodes
through reactive flooding. Zone Routing protocol (ZRP) is
one of the protocols that falls under this category. Since
both bandwidth and power are limited in mobile networks,
on-demand routing protocols are more widely used then
table-driven routing protocols. Among all proposed on-
demand routing protocols, AODV and DSR are most
commonly used protocols. The author uses AODV in this
thesis for experimentation purposes.
1.2 Load Balancing in MANETs
In traditional wired networks, load balancing can be
defined as a methodology to distribute or divide the traffic
load evenly across two or more network nodes in order to
mediate the communication and also achieve redundancy
in case one of the links fails. The other advantages of load
balancing can be optimal resource utilization, increased
throughput, and lesser overload. The load can also be
unequally distributed over multiple links by manipulating
the path cost involved. On the other hand, the objective of
load-balancing in MANETs is different from that of wired
networks due to mobility and limited resources like
bandwidth, transmission range and power. In mobile ad
hoc networks, balancing the load can evenly distribute the
traffic over the network and prevent early expiration of
overloaded nodes due to excessive power consumption in
forwarding packets. It can also allow an appropriate usage
of the available network resources. The existing ad-hoc
routing protocols do not have a mechanism to convey the
load information to the neighbours and cannot evenly
distribute the load in the network. It remains a major
drawback in MANETs that the nodes cannot support load
balancing among different routes over the network.
1.3 Need of Load Balancing in MANETS
On-demand routing protocols such as AODV initiate
the route discovery only if the current topology changes
and the current routes are not available. In high mobility
situations where the topology is highly dynamic, existing
links may break quickly. It may be safe to assume that in
such scenarios the on-demand routing protocols like
AODV and DSR can achieve load balancing effect
automatically by searching for new routes and using
different intermediate nodes to forward traffic. Whereas, in
the scenarios where the same intermediate nodes are used
for longer period of time, the on-demand behaviour may
create bottlenecks and cause network degradation due to
congestion and lead to long delays. In addition, the caching
mechanism in most on-demand routing protocols for
intermediate nodes to reply from cache, can cause
concentration of load on certain nodes. It had been shown
in [1] that the increase in traffic load degrades the network
performance in MANETs. In other words, if the topology
changes are minimal then this behaviour results in same
routes being used for a longer period of time which in turn
increases the traffic concentration on specific intermediate
nodes. It had been proved in [2] that the congestion and the
delay in delivering packets are increased with the
decreased mobility in on-demand routing. In addition, it
also increases the energy consumption at intermediate
nodes and has them expire early. This early expiration of
nodes can cause an increase in the control packets and the
transmission power of other nodes to compensate the loss.
Furthermore, it can result in network degradation and even
an early expiration of the entire ad-hoc network. Besides,
using a same node for routing traffic for a longer duration
may result in an uneven usage of the available network
resources, like bandwidth. A network is less reliable if the
load among network nodes is not well balanced.](https://image.slidesharecdn.com/loadawareandloadbalancingusingaomdvroutinginmanet-160518162011/85/Load-aware-and-load-balancing-using-aomdv-routing-in-manet-2-320.jpg)
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2. RELATED WORK
Several protocols have been developed for supporting
ad hoc multicast routing, i.e. MAODV [3] [4], ODMRP [5],
and CAMP [6]. However, these protocols did not address
the QoS aspects of ad hoc wireless communication. Only a
few protocols support QoS in multicast routing in mobile
ad hoc networks. Examples are QAMNet [7], QMR [8], E-
QMR [9] and Lantern-trees [10]. The QAMNet [7]
approach extends the mesh-based ODMRP multicast
routing protocol by introducing traffic prioritization,
distributed resource probing and admission control
mechanisms to provide QoS. For available bandwidth
estimation, it compared the threshold rate of real-time
traffic and current rate of real-time traffic. This is the same
as method of SWAN [11]. Similarly, it has many
difficulties to estimate the threshold rate accurately
because of its dependence to the traffic pattern. A lantern-
tree topology is used to provide QoS multicast routing in
[10]. This protocol shares time slots at the Mac layer and
uses a CDMA over TDMA channel model. In this model,
available bandwidth is measured in terms of the amount of
free slots. At start up, it shares time slots between all
neighbour nodes and finds a suitable scheduling of the free
slots. Its main disadvantage is the need for a centralized
MAC scheme in ad-hoc mobile networks with dynamic
wireless environments. M. Ali et al. [12] have proposed a
QoS aware routing protocol employing multi path routing
backbones using intermediate nodes which are rich in
resources like bandwidth, processing power, residual
energy etc. The protocol ensures that the available
bandwidth in the network is utilised efficiently by
distributing traffic evenly across multiple routing
backbones. Reddy and Raghavan [13] have proposed a
scalable multipath on-demand routing protocol (SMORT),
which reduces the routing overhead incurred in recovering
from route breaks, by using secondary paths. Though it
provides fail-safe multiple paths, it does not consider the
individual QoS characteristics of the nodes like bandwidth,
energy, load etc. A. Tsirigos, Z. J Hass [14] have found
that, under certain constraints on the path failure
probabilities, the probability of successful communication
of packets between source and destination increases with
number of paths used and can, in the limit, approach 100
percent. They have proposed a multipath scheme which
finds the optimal way to fragment and then distribute the
packets to the paths so that the probability of
reconstructing the original information at the destination is
maximised. Marina and Das [15] have proposed the
multipath version of the AODV protocol called AOMDV.
It is designed primarily for highly dynamic ad hoc
networks where frequent link failures and route breaks
occur. With multiple redundant paths, new route discovery
is needed only when all paths to the destination fail, unlike
AODV where a new route discovery is needed in response
to every route break. The AOMDV algorithm finds
multiple loop free link disjoint routes from source to
destination in the MANET. AOMDV performs better in
terms of delay, routing load and route discovery time
compared to the single path AODV. However these
multiple paths need not satisfy the QoS requirements of the
flow as the intermediate nodes taking part in the multiple
paths are not selected based on their ability to support the
QoS requirements. Ivascu et al. [16] have presented an
approach based on mobile routing backbone (MRB) for
supporting QoS in MANETs. Their QMRB-AODV
protocol identifies the nodes which have capabilities and
characteristics that will enable them to take part in the
MRB and efficiently participate in the routing process.
Their approach improves network throughput and packet
delivery ratio by directing traffic through lowly congested
regions of the network that are rich in resources. To build
routing backbones, they classify the nodes in the network
based on their characteristics as either QoS routing nodes,
simple routing nodes that route packets without any QoS
guarantee or transceiver nodes. However since only a
single MRB is identified between a source and destination,
frequent route breaks may happen in highly dynamics
networks leading to more frequent route re-discovery
processes and hence increased overheads.
3. PROPOSED METHOD
3.1 Problem Definition
In the field of mobile ad hoc networks routing protocols,
there are lot of problems to be tackled such as Quality of
service, routing optimization and security issues. My main
interest is in the security issues related to routing protocols
in MANETs. The work is done through Network
simulator-2 and measures network performance. Our aim
to minimize congestion using multipath routing with load
aware technique that provide low overhead and increases
performance of the network like throughput, packet
delivery ratio and also minimize average end-to-end delay.
3.2Proposed Work
3.2.1 Proposed methodology
According to problem statement , very first we create
mobile node and very first routing protocol as AOMDV
(Ad-hoc on demand multipath distance vector routing)
after next time we apply LAR routing for destination
expected zone finding and set channel type as wireless
channel , prorogation type two ray ground wave because
mobile node contain routing table and also node radio
range is limited so our data transmitted from node to node
after that we apply MAC ( media access control technique)
as 802.11 WLAN that provides radio range as our
dissertation work proposed in Enhance AOMDV with
location aided routing and control the congestion as well as
balance the load of the network here we describe LAR
working scheme and the define proposed algorithm.](https://image.slidesharecdn.com/loadawareandloadbalancingusingaomdvroutinginmanet-160518162011/85/Load-aware-and-load-balancing-using-aomdv-routing-in-manet-3-320.jpg)
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3.2.2 Working of LAR with respect to Location Tracking
System
Our first scheme uses a request zone that is rectangular
in shape (refer to figure 4). Assume that node S knows that
node D was at location (Xd, Yd) at time t0. At time t1,
node S initiates a new route discovery for destination D.
We assume that node S also knows the average speed v
with which D can move. Using this, node S defines the
expected zone at time t1 to be the circle of radius R = v (t1
� t0) cantered at location (Xd, Yd). (As stated before,
instead of the average speed, v may be chosen to be the
maximum speed or some other function of the speed
distribution.) In position-based routing, a Location-Aided
Routing, LAR [75] protocol is a position-based routing
protocol that discovers routes to destinations reactively. It
uses location information to reduce the routing overhead
caused by the route discovery process. Its main concept is
to confine the propagation area of the route request (RREQ)
messages to the geographical zone that leads to the
destination node. For this reason, LAR defines two zones:
expected zone and request zone. The expected zone,
illustrated in Figure 2, is the circle where the destination
node is expected to be located.
Fig: 1 LAR request and expected zones
The source node, only, broadcasts the discovery
request within the request zone, which is the smallest
rectangle formed by the expected zone and the source
node’s position. Furthermore, LAR defines two schemes:
scheme-1 and scheme-2. The difference resides in the way
the request zone is specified within the request message. In
the scheme-1, the source node explicitly specifies the
request zone by including the coordinates of the zone’s
four corners in the RREQ. The receivers located outside
the specified rectangle discards the RREQ. On the other
hand, in scheme-2, the source node includes in the RREQ
the destination’s coordinates as well as its distance, Dists,
to the destination. The receiving nodes will then calculate
their distance to the destination node, and only the nodes
whose distance is greater than Dists will forward the
RREQ.
3.3 Proposed Algorithm
Here we design algorithm for Enhance AOMDV with
location aware routing under MANET, in algorithm very
first we create sender and receiver node’s and configure
routing protocol to each node as AOMDV, that routing
protocol uses alternative path means each communication
uses two path name as incoming and outgoing path that
balance the load of all existing path and uses equal priority
base resource after that in internal module we add location
aware routing that provide estimated location of destination
to the source that LAR protocol minimize routing overhead
because every communication failure case routing packet
broadcasted by the sender node but the our LAR module
minimize routing broadcasting to all direction into only
specific estimated location direction. in external TCL (tool
command language) very first we set initial network
parameter like physical parameter, MAC protocol channel
type, antenna type and routing protocol after that we create
mobile node with sender and receiver node and routing as
AOMDV after that compute route function call and
discover route from source to destination on the bases of
shortest path for transmissions and alternative path for
acknowledge incoming into the sender node, if route break
in certain time so route function repetitive call and
broadcast route packet that increases route overhead so we
use LAR (location aware routing) that module is very use
full for route overhead minimization, that case receiver
node send location information to the sender node time to
time manner and useful for route discovery process and
route packet flood only expected zone on the bases of
previous location table, here we deploy algorithm step by
step in below.
Mobile node = N; // Number of mobile nodes
Sender node = S; // sub set of N
Receiver Node = R; //sub Set of N
Receiver Routing = LAR; // Location aware routing
Start simulation time = t0
Set routing protocol = AOMDV;
Set MAC = 802.11
Set radio range = rr; //initialize radio range
RREQ_B(S, R, rr)
{
If ((rr<=550) && (next hop >0))
{
Compute route ()
{
rtable->insert (rtable-
>rt_nexthop); // nexthop to
RREQ source
rtable1->insert (rtable1-
>rt_nexthop); // nexthop to
RREQ destination
if (dest==true)](https://image.slidesharecdn.com/loadawareandloadbalancingusingaomdvroutinginmanet-160518162011/85/Load-aware-and-load-balancing-using-aomdv-routing-in-manet-4-320.jpg)
![209
{send ack to source
node with rtable1;
Data_packet_send
(s_no, nexthop, type,
rtable)
Receiver R uses LAR routing;
Receiver send expected location and speed information to
sender;
If (node updates location)
{
Use location info and sender send routing packet to
expected zone;
If (dest == true)
{
Data_packet_send (s_no, nexthop, type)
}
}}
else {
destination not found;
}
}
else {destination un-reachable;
} }
3.3 Proposed Working Architecture
Fig: 2 Proposed working architecture
In above structure present working architecture of our
proposed model, basically our module divides into three
part internal structure, intermediate and output result
format, very firs we explain about internal structure of NS-
2, initially we deploy node and apply routing protocol as
AOMDV, after that in internal module we inbuilt MAC as
802.11 scheme for that purpose we updated internal file
Make. in, ns-lib.tcl, packet.h and cmutrace.cc after that
we add third and important part of routing minimization
that is LAR module and same above procedure follow if all
the module successfully compile and cerate object file than
we work in intermediate structure, in that case we create
mobile node through the TCL (tool command language)
and set mobile ad-hoc network basic parameter here we
also apply initial energy of each node, LAR (location
aware routing) for destination location aware and routing
protocol as DSR and MAC as 802.11 that create the radio
range of the node’s. in this module sender node initiate
routing discovery process so sender use as AOMDV
routing and broadcast routing protocol and same time we
also search alternative path for acknowledgment sending
that minimize congestion in one existing path but node
change self-position and break the communication link
than LAR module are work important role for re-
establishing of route from source to destination that uses
expected zone base route broadcast technique and
minimize routing overhead after that we analyse our result
through generated trace file and apply third or output
module that case we pass output generated trace file into
awk (abstract window tool kit) and analyse the result of our
proposed work and conclude.
Fig: 3 Proposed working architecture
4. RESULT ANALYSIS
4.1 Simulation Environment
The detailed simulation model is based on
network simulator-2 (ver-2.31), is used in the evaluation.
The NS instructions can be used to define the topology
structure of the network and the motion mode of the nodes,
to configure the service source and the receiver etc.
4.2 Data Collection and Implementation Strategy
For data collection and implementation we will use
Network Simulator-2 (NS-2). The description about
simulation environment is as follows: Network simulator 2
(NS2) is the result of an on-going effort of research and
development that is administrated by researchers at
Berkeley [17]. It is a discrete event simulator targeted at](https://image.slidesharecdn.com/loadawareandloadbalancingusingaomdvroutinginmanet-160518162011/85/Load-aware-and-load-balancing-using-aomdv-routing-in-manet-5-320.jpg)
![211
Fig: 5 Packet Delivery Ration Analyses
4.6.4 Throughput Analysis
In wireless communication networks, such as packet radio,
throughput or network throughput is the average rate of
successful message delivery over a communication
channel.
Fig: 6 Routing Load Analysis
Fig: 7 Throughput Analyses.
This data may be delivered over a logical or physical link,
or pass through a certain wireless network node. The
throughput is regularly measured in bits per second (bit/s
or bps), and occasionally in data packets per second or data
packets per time slot. In this graph it is observe that in
normal AOMDV and E-AOMDV time, throughput value
of normal AOMDV is nearly 900. And throughput of E-
AOMDV is 1300 maximum. E-AOMDV gives better result
than normal AOMDV time.
5. CONCLUSION AND FUTURE WORK
In this paper we proposed Load aware and load balancing
using AOMDV routing in MANET. In this work we are
going to design an efficient system for load aware routing
protocol with load balancing mechanism using AOMDV
routing in mobile ad-hoc network, so that we can minimize
routing overhead of the network and also increase the life
time of the network. As per simulation result enhanced or
load balanced E-AOMDV is better than normal AOMDV.
Here we analyze AOMDV and E-AODMV in future we
also work in the field of secruity constrant under MANET.
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[18]. http://www.isi.edu/nsnam/ns/](https://image.slidesharecdn.com/loadawareandloadbalancingusingaomdvroutinginmanet-160518162011/85/Load-aware-and-load-balancing-using-aomdv-routing-in-manet-8-320.jpg)
Load aware and load balancing using aomdv routing in manet
- 1. 205 Load Aware and Load Balancing using AOMDV Routing in MANET Rakhi Sharma1 , Dr. Sitesh Kumar Sinha2 , Prof. Mukesh Kumar3 Computer Science, AISECT University, Bhopal, India 1 rakhisharma@gmail.com, 2 siteshkumarsinha@gmail.com, 3 goutam.mukesh@gmail.com Abstract--Effective load balancing has been a demanding task in MANET due to their dynamic and un-predictable nature and topology change. Nodes in MANETs greatly differ with each other in terms of communication and processing power. For effective working of MANET multiple routing backbones are identified from source to destination using intermediate nodes that have better communication and processing capabilities to take part in the mobile routing backbones and efficiently participate in the routing process. In addition to improved load balancing, the new method also provides enhanced Quality of Service (QoS) support and congestion control as per existing network traffic levels and nodes' processing loads. In this paper we are going to propose a Load aware and load balancing techniques using multipath routing. Keywords: - AODV, DREAM, QoS, Routing Load, Packet Delivery Ratio. 1. INTRODUCTION Mobile ad hoc network (MANET) is a group of mobile nodes where each node is free to move about arbitrarily. Each node logically contains a router that may have multiple hosts and that also may have multiple wireless communication devices. A MANET is self organizing, adaptive and infrastructure less; AODV currently does not support Quality of Service (QoS) and also has no load balancing mechanism. The QoS routing feature is important in a stand-alone multi hop mobile network for real-time applications and also for a mobile network to interconnect wired networks with QoS support. The first extension (named QoS field) specifies the service requirements (maximum delay is chosen), which must be met by nodes rebroadcasting a Route Request or returning a Route Reply for a destination. A comprehensive packet- layer simulation model through media access control (MAC) and physical layer models is used to study the performance of both the AODV and the QoS-AODV protocols. We extend the ns-2 (network simulator version 2) to include the proposed QoS-AODV protocol, delay constraints, topological rate of change and mobility speeds. A multicast packet is delivered to all the receivers belong to a group along a network structure such as tree or mesh that is constructed once a multicast group is created. However because of node mobility the network structure is brittle and thus, the multicast packet may not be delivered to some members. To recompense this problem and to get better packet delivery ratio, multicast protocols for ad-hoc networks usually employ control packets to periodically refresh the network structure. 1.1 Routing in MANETs Routing protocols for MANETs are dynamic in nature and require each node to store routing information about destinations that are needed to be reached and also update that information as the network topology changes. A significant number of routing protocols have been suggested for these networks. 1.1.1 Position-based routing protocols These protocols make the routing decisions based on nodes‟ geographical coordinates. Each node maintains an updated location table that contains the geographical position of all its neighbours. The routing decisions are made based on the neighbours‟ coordinates and trajectory information towards the destination location. Two of the position based protocols are Simple Forwarding over Trajectory (SIFT) and Distance Routing Effect Algorithm for Mobility (DREAM). 1.1.2 Topology-based routing protocols Classical routing approaches for MANETs are topology-based in which the routing decisions are based on links among network nodes. In other words, these protocols are link-driven. A routing table is maintained which contains the route to destinations and an existing link pointing towards it. If a node moves resulting in a link break then the route needs to be recomputed. These protocols can further be classified as Table-driven or Proactive, Source-initiated (On demand) or Reactive and Hybrid routing protocols. 1.1.3 Table-driven routing protocols Proactive routing protocols monitor the topology of the network at all times and pre-compute paths between any source and destination. Routes are maintained for all nodes, even for nodes to which no data has been sent. This is done by periodically exchanging routing tables throughout the network, similar to traditional wired networks. These protocols maintain tables at each node which stores updated routing information for every node to every other node within the network. An advantage of these routing protocols is that obtaining the required route information and establishing a session will not be time-consuming. A disadvantage of these routing protocols is that it will react to topology changes even when no traffic is affected by
- 2. 206 that change, which is extremely resource-consuming and will result in the unnecessary usage of bandwidth even when no data is transferred. Another drawback is more power consumption due to periodic exchange of information. Examples of such protocols are Destination- Sequenced Distance-Vector Routing protocol (DSDV), Optimized Link State Routing (OLSR), Cluster head Gateway Switch Routing (CGSR) protocol, The Wireless Routing Protocol (WRP). 1.1.4 On-demand routing protocols Reactive routing protocols find a route only when there is a demand for data transmission, i.e., at the beginning of a connection. In other words, the route discovery process begins whenever a source node needs a route to a destination in on-demand routing. A route between two hosts is determined only when there is an explicit need to forward packets. This is done by initiating a route discovery within the network by flooding the entire network with route request (RREQ) packets. Also, once a route is established, it is maintained in the routing table until the destination is out overhead is significantly reduced, since the routing information does not have to be updated periodically, and no maintenance is done on routes that are not being used. One disadvantage of these protocols is the latency that occurs when a route is required. However, for highly mobile networks, these protocols show better performance for MANETs. Few examples of such protocols are Ad Hoc On-Demand Distance Vector (AODV) routing protocol, Dynamic Source Routing (DSR) protocol, Temporally Ordered Routing Algorithm (TORA) and Associativity-Based Routing (ABR). 1.1.5 Hybrid routing protocols On-demand routing has relatively less routing overhead, since it eliminates periodic flooding of the network with update messages. But it suffers high routing delay when compared to table-driven routing. Table driven routing ensures high quality in static topologies but cannot be extended to mobile networks. Combining the advantages of both, a few hybrid routing protocols have been designed, whereby the routing is first initiated with some proactive routes and then serves the demand from other nodes through reactive flooding. Zone Routing protocol (ZRP) is one of the protocols that falls under this category. Since both bandwidth and power are limited in mobile networks, on-demand routing protocols are more widely used then table-driven routing protocols. Among all proposed on- demand routing protocols, AODV and DSR are most commonly used protocols. The author uses AODV in this thesis for experimentation purposes. 1.2 Load Balancing in MANETs In traditional wired networks, load balancing can be defined as a methodology to distribute or divide the traffic load evenly across two or more network nodes in order to mediate the communication and also achieve redundancy in case one of the links fails. The other advantages of load balancing can be optimal resource utilization, increased throughput, and lesser overload. The load can also be unequally distributed over multiple links by manipulating the path cost involved. On the other hand, the objective of load-balancing in MANETs is different from that of wired networks due to mobility and limited resources like bandwidth, transmission range and power. In mobile ad hoc networks, balancing the load can evenly distribute the traffic over the network and prevent early expiration of overloaded nodes due to excessive power consumption in forwarding packets. It can also allow an appropriate usage of the available network resources. The existing ad-hoc routing protocols do not have a mechanism to convey the load information to the neighbours and cannot evenly distribute the load in the network. It remains a major drawback in MANETs that the nodes cannot support load balancing among different routes over the network. 1.3 Need of Load Balancing in MANETS On-demand routing protocols such as AODV initiate the route discovery only if the current topology changes and the current routes are not available. In high mobility situations where the topology is highly dynamic, existing links may break quickly. It may be safe to assume that in such scenarios the on-demand routing protocols like AODV and DSR can achieve load balancing effect automatically by searching for new routes and using different intermediate nodes to forward traffic. Whereas, in the scenarios where the same intermediate nodes are used for longer period of time, the on-demand behaviour may create bottlenecks and cause network degradation due to congestion and lead to long delays. In addition, the caching mechanism in most on-demand routing protocols for intermediate nodes to reply from cache, can cause concentration of load on certain nodes. It had been shown in [1] that the increase in traffic load degrades the network performance in MANETs. In other words, if the topology changes are minimal then this behaviour results in same routes being used for a longer period of time which in turn increases the traffic concentration on specific intermediate nodes. It had been proved in [2] that the congestion and the delay in delivering packets are increased with the decreased mobility in on-demand routing. In addition, it also increases the energy consumption at intermediate nodes and has them expire early. This early expiration of nodes can cause an increase in the control packets and the transmission power of other nodes to compensate the loss. Furthermore, it can result in network degradation and even an early expiration of the entire ad-hoc network. Besides, using a same node for routing traffic for a longer duration may result in an uneven usage of the available network resources, like bandwidth. A network is less reliable if the load among network nodes is not well balanced.
- 3. 207 2. RELATED WORK Several protocols have been developed for supporting ad hoc multicast routing, i.e. MAODV [3] [4], ODMRP [5], and CAMP [6]. However, these protocols did not address the QoS aspects of ad hoc wireless communication. Only a few protocols support QoS in multicast routing in mobile ad hoc networks. Examples are QAMNet [7], QMR [8], E- QMR [9] and Lantern-trees [10]. The QAMNet [7] approach extends the mesh-based ODMRP multicast routing protocol by introducing traffic prioritization, distributed resource probing and admission control mechanisms to provide QoS. For available bandwidth estimation, it compared the threshold rate of real-time traffic and current rate of real-time traffic. This is the same as method of SWAN [11]. Similarly, it has many difficulties to estimate the threshold rate accurately because of its dependence to the traffic pattern. A lantern- tree topology is used to provide QoS multicast routing in [10]. This protocol shares time slots at the Mac layer and uses a CDMA over TDMA channel model. In this model, available bandwidth is measured in terms of the amount of free slots. At start up, it shares time slots between all neighbour nodes and finds a suitable scheduling of the free slots. Its main disadvantage is the need for a centralized MAC scheme in ad-hoc mobile networks with dynamic wireless environments. M. Ali et al. [12] have proposed a QoS aware routing protocol employing multi path routing backbones using intermediate nodes which are rich in resources like bandwidth, processing power, residual energy etc. The protocol ensures that the available bandwidth in the network is utilised efficiently by distributing traffic evenly across multiple routing backbones. Reddy and Raghavan [13] have proposed a scalable multipath on-demand routing protocol (SMORT), which reduces the routing overhead incurred in recovering from route breaks, by using secondary paths. Though it provides fail-safe multiple paths, it does not consider the individual QoS characteristics of the nodes like bandwidth, energy, load etc. A. Tsirigos, Z. J Hass [14] have found that, under certain constraints on the path failure probabilities, the probability of successful communication of packets between source and destination increases with number of paths used and can, in the limit, approach 100 percent. They have proposed a multipath scheme which finds the optimal way to fragment and then distribute the packets to the paths so that the probability of reconstructing the original information at the destination is maximised. Marina and Das [15] have proposed the multipath version of the AODV protocol called AOMDV. It is designed primarily for highly dynamic ad hoc networks where frequent link failures and route breaks occur. With multiple redundant paths, new route discovery is needed only when all paths to the destination fail, unlike AODV where a new route discovery is needed in response to every route break. The AOMDV algorithm finds multiple loop free link disjoint routes from source to destination in the MANET. AOMDV performs better in terms of delay, routing load and route discovery time compared to the single path AODV. However these multiple paths need not satisfy the QoS requirements of the flow as the intermediate nodes taking part in the multiple paths are not selected based on their ability to support the QoS requirements. Ivascu et al. [16] have presented an approach based on mobile routing backbone (MRB) for supporting QoS in MANETs. Their QMRB-AODV protocol identifies the nodes which have capabilities and characteristics that will enable them to take part in the MRB and efficiently participate in the routing process. Their approach improves network throughput and packet delivery ratio by directing traffic through lowly congested regions of the network that are rich in resources. To build routing backbones, they classify the nodes in the network based on their characteristics as either QoS routing nodes, simple routing nodes that route packets without any QoS guarantee or transceiver nodes. However since only a single MRB is identified between a source and destination, frequent route breaks may happen in highly dynamics networks leading to more frequent route re-discovery processes and hence increased overheads. 3. PROPOSED METHOD 3.1 Problem Definition In the field of mobile ad hoc networks routing protocols, there are lot of problems to be tackled such as Quality of service, routing optimization and security issues. My main interest is in the security issues related to routing protocols in MANETs. The work is done through Network simulator-2 and measures network performance. Our aim to minimize congestion using multipath routing with load aware technique that provide low overhead and increases performance of the network like throughput, packet delivery ratio and also minimize average end-to-end delay. 3.2Proposed Work 3.2.1 Proposed methodology According to problem statement , very first we create mobile node and very first routing protocol as AOMDV (Ad-hoc on demand multipath distance vector routing) after next time we apply LAR routing for destination expected zone finding and set channel type as wireless channel , prorogation type two ray ground wave because mobile node contain routing table and also node radio range is limited so our data transmitted from node to node after that we apply MAC ( media access control technique) as 802.11 WLAN that provides radio range as our dissertation work proposed in Enhance AOMDV with location aided routing and control the congestion as well as balance the load of the network here we describe LAR working scheme and the define proposed algorithm.
- 4. 208 3.2.2 Working of LAR with respect to Location Tracking System Our first scheme uses a request zone that is rectangular in shape (refer to figure 4). Assume that node S knows that node D was at location (Xd, Yd) at time t0. At time t1, node S initiates a new route discovery for destination D. We assume that node S also knows the average speed v with which D can move. Using this, node S defines the expected zone at time t1 to be the circle of radius R = v (t1 � t0) cantered at location (Xd, Yd). (As stated before, instead of the average speed, v may be chosen to be the maximum speed or some other function of the speed distribution.) In position-based routing, a Location-Aided Routing, LAR [75] protocol is a position-based routing protocol that discovers routes to destinations reactively. It uses location information to reduce the routing overhead caused by the route discovery process. Its main concept is to confine the propagation area of the route request (RREQ) messages to the geographical zone that leads to the destination node. For this reason, LAR defines two zones: expected zone and request zone. The expected zone, illustrated in Figure 2, is the circle where the destination node is expected to be located. Fig: 1 LAR request and expected zones The source node, only, broadcasts the discovery request within the request zone, which is the smallest rectangle formed by the expected zone and the source node’s position. Furthermore, LAR defines two schemes: scheme-1 and scheme-2. The difference resides in the way the request zone is specified within the request message. In the scheme-1, the source node explicitly specifies the request zone by including the coordinates of the zone’s four corners in the RREQ. The receivers located outside the specified rectangle discards the RREQ. On the other hand, in scheme-2, the source node includes in the RREQ the destination’s coordinates as well as its distance, Dists, to the destination. The receiving nodes will then calculate their distance to the destination node, and only the nodes whose distance is greater than Dists will forward the RREQ. 3.3 Proposed Algorithm Here we design algorithm for Enhance AOMDV with location aware routing under MANET, in algorithm very first we create sender and receiver node’s and configure routing protocol to each node as AOMDV, that routing protocol uses alternative path means each communication uses two path name as incoming and outgoing path that balance the load of all existing path and uses equal priority base resource after that in internal module we add location aware routing that provide estimated location of destination to the source that LAR protocol minimize routing overhead because every communication failure case routing packet broadcasted by the sender node but the our LAR module minimize routing broadcasting to all direction into only specific estimated location direction. in external TCL (tool command language) very first we set initial network parameter like physical parameter, MAC protocol channel type, antenna type and routing protocol after that we create mobile node with sender and receiver node and routing as AOMDV after that compute route function call and discover route from source to destination on the bases of shortest path for transmissions and alternative path for acknowledge incoming into the sender node, if route break in certain time so route function repetitive call and broadcast route packet that increases route overhead so we use LAR (location aware routing) that module is very use full for route overhead minimization, that case receiver node send location information to the sender node time to time manner and useful for route discovery process and route packet flood only expected zone on the bases of previous location table, here we deploy algorithm step by step in below. Mobile node = N; // Number of mobile nodes Sender node = S; // sub set of N Receiver Node = R; //sub Set of N Receiver Routing = LAR; // Location aware routing Start simulation time = t0 Set routing protocol = AOMDV; Set MAC = 802.11 Set radio range = rr; //initialize radio range RREQ_B(S, R, rr) { If ((rr<=550) && (next hop >0)) { Compute route () { rtable->insert (rtable- >rt_nexthop); // nexthop to RREQ source rtable1->insert (rtable1- >rt_nexthop); // nexthop to RREQ destination if (dest==true)
- 5. 209 {send ack to source node with rtable1; Data_packet_send (s_no, nexthop, type, rtable) Receiver R uses LAR routing; Receiver send expected location and speed information to sender; If (node updates location) { Use location info and sender send routing packet to expected zone; If (dest == true) { Data_packet_send (s_no, nexthop, type) } }} else { destination not found; } } else {destination un-reachable; } } 3.3 Proposed Working Architecture Fig: 2 Proposed working architecture In above structure present working architecture of our proposed model, basically our module divides into three part internal structure, intermediate and output result format, very firs we explain about internal structure of NS- 2, initially we deploy node and apply routing protocol as AOMDV, after that in internal module we inbuilt MAC as 802.11 scheme for that purpose we updated internal file Make. in, ns-lib.tcl, packet.h and cmutrace.cc after that we add third and important part of routing minimization that is LAR module and same above procedure follow if all the module successfully compile and cerate object file than we work in intermediate structure, in that case we create mobile node through the TCL (tool command language) and set mobile ad-hoc network basic parameter here we also apply initial energy of each node, LAR (location aware routing) for destination location aware and routing protocol as DSR and MAC as 802.11 that create the radio range of the node’s. in this module sender node initiate routing discovery process so sender use as AOMDV routing and broadcast routing protocol and same time we also search alternative path for acknowledgment sending that minimize congestion in one existing path but node change self-position and break the communication link than LAR module are work important role for re- establishing of route from source to destination that uses expected zone base route broadcast technique and minimize routing overhead after that we analyse our result through generated trace file and apply third or output module that case we pass output generated trace file into awk (abstract window tool kit) and analyse the result of our proposed work and conclude. Fig: 3 Proposed working architecture 4. RESULT ANALYSIS 4.1 Simulation Environment The detailed simulation model is based on network simulator-2 (ver-2.31), is used in the evaluation. The NS instructions can be used to define the topology structure of the network and the motion mode of the nodes, to configure the service source and the receiver etc. 4.2 Data Collection and Implementation Strategy For data collection and implementation we will use Network Simulator-2 (NS-2). The description about simulation environment is as follows: Network simulator 2 (NS2) is the result of an on-going effort of research and development that is administrated by researchers at Berkeley [17]. It is a discrete event simulator targeted at
- 6. 210 networking research. It provides extensive support for simulation of TCP, routing, and multipath protocol. The simulator is written in C++ and a script language called OTcl2. Ns use an OTcl interpreter towards the user. This means that user writes an OTcl script that defines the network (number of nodes, links), the traffic in the network (sources, destinations, type of traffic) and which protocols it will use. This script is used by ns during the simulations. The result obtained from the simulations is an output file known as trace file that can be used to doing data processing (throughput, calculate delay etc) and to visualize the simulation with a program called Network Animator. 4.3 Basic Simulator Architecture Fig: Basic simulator architecture 4.4 Simulation Parameter We get Simulator Parameter like Number of nodes, Dimension, Routing protocol, traffic etc. According to below table 1 we simulate our network. Table 1: Simulation Parameter 4.5 Performance Evaluation There are following different performance metrics have showed the results on the basis of following: Routing overhead: This metric describes how many routing packets for route discovery and route maintenance need to be sent so as to propagate the data packets. Average Delay: This metric represents average end-to-end delay and indicates how long it took for a packet to travel from the source to the application layer of the destination. It is measured in seconds. Throughput: This metric represents the total number of bits forwarded to higher layers per second. It is measured in bps. It can also be defined as the total amount of data a receiver actually receives from sender divided by the time taken by the receiver to obtain the last packet. Packet Delivery Ratio: The ratio between the amount of incoming data packets and actually received data packets. 4.6 Results This section represents the results that are calculated on the basis of simulation parameters 4.6.1 TCP Analysis In this simulation Two TCP connection with TCP normal AOMDV case and TCP at Enhanced AOMDV (with load balancing) were created and analyze the comparative result between them. In given graph result shows x-coordinate as simulation time in seconds and y-coordinate represents window size, according to result output it is observed that maximum window size which TCP normal AOMDV case reached 33 units and TCP E-AOMDV reached maximum 60 units in data transfer. According to simulation result it is observed that the performance of TCP E-AOMDV is much higher. Fig: 4 TCP Analyses 4.6.2 Packet Delivery Ratio Analysis Packet delivery fraction (ratio) is a ratio of no of receives packets from no of packets transmitted per time unit. According to graph shown below, PDF of normal AOMDV case shown by red line and PDF of Enhanced AOMDV (E-AOMDV) case shown with green line As per result obtained higher PDF value of Normal AOMDV case is nearly 96 % and higher PDF value of E-AOMDV case is nearly 99 %. As per graph E-AOMDV approach shows better result than normal AOMDV. 4.6.3 Routing Load Analysis Routing load is calculated as the total number routing packets are transmitted over the successful data transmission. The increase in the routing load reduces the performance of the ad-hoc network as it consumes portions from the bandwidth available to transfer data between the nodes. As per graph shown, it is observed that routing load of normal AOMDV time (shown in Red line) was higher than enhanced E-AOMDV time (shown in Green line). Hence according to routing load analysis it is clear that E- AOMDV is better than normal AOMDV.
- 7. 211 Fig: 5 Packet Delivery Ration Analyses 4.6.4 Throughput Analysis In wireless communication networks, such as packet radio, throughput or network throughput is the average rate of successful message delivery over a communication channel. Fig: 6 Routing Load Analysis Fig: 7 Throughput Analyses. This data may be delivered over a logical or physical link, or pass through a certain wireless network node. The throughput is regularly measured in bits per second (bit/s or bps), and occasionally in data packets per second or data packets per time slot. In this graph it is observe that in normal AOMDV and E-AOMDV time, throughput value of normal AOMDV is nearly 900. And throughput of E- AOMDV is 1300 maximum. E-AOMDV gives better result than normal AOMDV time. 5. CONCLUSION AND FUTURE WORK In this paper we proposed Load aware and load balancing using AOMDV routing in MANET. In this work we are going to design an efficient system for load aware routing protocol with load balancing mechanism using AOMDV routing in mobile ad-hoc network, so that we can minimize routing overhead of the network and also increase the life time of the network. As per simulation result enhanced or load balanced E-AOMDV is better than normal AOMDV. Here we analyze AOMDV and E-AODMV in future we also work in the field of secruity constrant under MANET. REFERENCES [1]. M. Ali, B. G Stewart, A Shahrabi, A Vallavaraj “Multipath Routing Backbones For Load Balancing In Mobile Ad Hoc Networks”, 16th IEEE Mediterranean Electro technical Conference on (MELECON), pp. 749 - 752, 2012. [2]. P. Johanson, T. Larsson, N. Hedman, B. Mielczarek, and M. Degermark, Scenario-based Performance Analysis of Routing Protocols for Mobile Ad-hoc Networks,” Proceedings of ACM/IEEE MOBICOM'99, Seattle, WA, August 1999, pp. 195-206. [3]. Das, S.R., Perkins, C. E., Royer, E.M.: Performance Comparison of Two On demand Routing Protocols for Ad hoc Networks. Proc. IEEE INFOCOM (2000) 3–12 45 [4]. E. Royer and C. Perkins, (2000, Jul.). Multicast ad hoc on-demand distance vector (MAODV) routing. IETF Intemet Draft. [5]. E.M. Royer, and C. E. Perkins, “Multicast operation of the ad hoc on-demand distance vector routing protocol,” in Proc. 5th Annual ACM/IEEE Int. Conf. Mobile Computing and Networking, Seattle, WA, 1999, pp. 207-217. [6]. S. J. Lee, M. Gerla, and C. C. Chiang, “On-demand multicast routing protocol,” in Proc. IEEE Wireless Communications and Networking Conf. New Orleans, LA, 1999, pp. 1298-1302. [7]. J. Garcia-Luna-Aceves and E. Madruga, “The Core Assisted Mesh Protocol,” IEEE J. Selected Areas in Communications, vol. 17, no. 8, 1999, pp. 1380-1394. [8]. H. Tebbe and A. Kassler, “QAMNet: Providing Quality of Service to Ad-hoc Multicast Enabled Networks,” 1st International Symposium on Wireless Pervasive Computing (ISWPC), Thailand, 2006, pp. 1-5. [9]. M. Saghir, T. C. Wan and R. Budiarto, “Load Balancing QoS Multicast Routing Protocol in Mobile Ad Hoc Networks,” AINTEC, Bangkok, Thailand, vol. 3837, 2005, pp. 83-97.
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