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BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
CHAPTER 1
INTRODUCTION
1.1 About the Project
A fundamental problem in mobile ad hoc networks is asymmetry. Asymmetric or
unidirectional links arise in the network for several reasons: Devices transmitting with
different powers explicitly cause unidirectional links. Even when the devices are
transmitting at the same power, noise sources near a device that affect packet reception at
that device more than others may create unidirectional links. Finally, other intractable
factors such as barriers and environmental conditions that affect signal propagation also
lead to asymmetry.
Unidirectional Link Routing (UDLR) proposes a protocol that invokes tunneling
and encapsulation to send multi-hop acknowledgments at the link layer. However, the
protocol does not specify what routes are used for the multi-hop tunnels.
Fig. 1.1 A unidirectional ad hoc network. A → B is a unidirectional link, and B → C → A is its reverse route.
Reverse route forwarding is used for finding reverse routes for unidirectional
links in an asymmetric network is non-trivial. While it may appear that a straightforward
application of a standard distance-vector or link-state algorithm will provide the
necessary reverse route information, several problems arise while applying them in an
asymmetric network.
Dept of ISE, RLJIT 1
BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
Switch is a device that channels incoming data from any of multiple input ports to
the specific output port that will take the data toward its intended destination.
Disadvantage: If we use switch between any two networks we need more than
one switch to connect between them and the cost will also increases.
R outer is a device that forwards data packets along networks. A router is
connected to at least two networks, commonly two LANs or WANs or a LAN and its
ISP's network.
Routers are located at gateways, the places where two or more networks connect,
and are the critical device that keeps data flowing between networks and keeps the
networks connected to the Internet. When data is sent between locations on one network
or from one network to a second network the data is always seen and directed to the
correct location by the router.
There are mainly two types of Scheduling namely the system level scheduling
and the application level scheduling. The scheduling system will analyze the load
situation of every node and select one node to run the job. The scheduling policy is to
optimize the total performance of the whole system. If the system is heavily loaded, the
scheduling system has to realize the load balancing and increase the throughput and
resource utilization under restricted conditions. This kind of scheduling is known as the
system level scheduling.
If multiple jobs arrive within a unit scheduling time slot, the scheduling system
shall allocate an appropriate number of jobs to every node in order to finish these jobs
under a defined objective. Obviously, the objective is usually the minimal average
execution time. This scheduling policy is application-oriented so we call it application-
level scheduling.
Data mining, the extraction of hidden predictive information from large
databases, is a powerful new technology with great potential to help companies focus on
the most important information in their data warehouses.
Dept of ISE, RLJIT 2
BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
CHAPTER 2
LITERATURE SURVEY
This work first presents a simulation study quantifying the impact of asymmetric
links on network connectivity and routing performance. It then presents a framework
called BRA that provides a bidirectional abstraction of the asymmetric network to routing
protocols.
Extensive simulations of AODV layered on BRA show that packet delivery
increases substantially (two-fold in some instances) in asymmetric networks compared to
regular AODV, which only routes on bidirectional links.
Routing with BRA
BRA provides essential services to enable routing on asymmetric
networks. We expect BRA to operate as a sub-layer between the
current routing and the MAC layers in the network stack. If the system
implementation prohibits modifications to the network stack, then BRA
can be integrated with the routing protocol. While this integration will
require changes to the routing protocol, the changes are minimal. BRA
should not be completely transparent, that is, a routing protocol
layered on top of BRA is expected to be aware of the nature of links
they are routing over. This non-transparency allows routing protocols
to use the services of BRA intelligently and only upon necessity.
For instance, a routing protocol that cannot distinguish whether
two nodes are connected through a direct link or a multi-hop reverse
route might mistake the reverse route for a fast, direct-hop route and
route packets through the longer route; such an action may increase
the cost of routing, introduces additional congestion in the network,
and decreases the overall throughput of the system.
The services that BRA offers are: reverse route forwarding (“A
loop free extended Bellman-Ford routing protocol without bouncing effect,”[8]),
reliable packet delivery, and link status monitoring. The rest of
Dept of ISE, RLJIT 3
BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
this section describes these services in detail. “A Bidirectional Routing
Abstraction for Asymmetric Mobile Ad Hoc Network” [1].
Link-state protocols such as OLSR [2] maintain a view of the
network topology at each node; nodes broadcast their views of the
topology to their neighbors and in turn update their topology views
based on their neighbors’ state. Clearly, with a complete view of the
network, link-state protocols do not have a problem finding routes in an
asymmetric networks. Practical implementations of link-state protocols,
however, maintain partial views in order to reduce the worst-case
message complexity, where denotes the number of nodes; the partial
views may not have sufficient information to handle unidirectional
links. “A tunneling approach used in our project for routing with unidirectional links in
mobile ad hoc networks,” [2].
AODV Algorithm
On-demand protocols such as AODV [3] further decrease the
routing overhead by maintaining routes only when required for
communication.In typical on-demand protocols, a source node S that
requires to communicate with a destination node D first initiates a
route discovery process, where a route request packet (RREQ) is
broadcast typically to the entire network. The destination, or another
intermediate node that knows a route to the destination, sends a route
reply (RREP) back to the source upon receiving the RREQ.
Typically, the RREP is sent along the discovered path in the
reverse direction. The state about the discovered path is either
retained at each intermediate node (as in AODV) or carried along with
each packet (as in DSR). If the current route to the destination breaks,
a process similar to route discovery is performed to repair the route.
“Ad-hoc on demand distance vector (AODV) routing,” [3].
The Distributed Bellman–Ford Algorithm is a well-known
distance-vector algorithm to obtain the shortest routes between pairs
of nodes in a bidirectional network. This algorithm has practical
Dept of ISE, RLJIT 4
BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
advantages because it works asynchronously and is guaranteed to
converge eventually if the network is not partitioned and remains
stable for sufficient time. “A loop free extended Bellman-Ford routing
protocol without bouncing effect,”[4].
Java have two things: a programming language and a platform. Java The
complete reference [6].
Java is also unusual in that each Java program is both compiled and interpreted.
With a compile you translate a Java program into an intermediate language called Java
byte codes the platform-independent code instruction is passed and run on the computer.
Compilation happens just once; interpretation occurs each time the program is
executed. The figure illustrates how this works.
Figure 2.1 Compilation and Interpretation of Java Program
You can think of Java byte codes as the machine code instructions for the Java
Virtual Machine (Java VM). Every Java interpreter, whether it’s a Java development
tool or a Web browser that can run Java applets, is an implementation of the Java VM.
The Java VM can also be implemented in hardware.
Java byte codes help make “write once, run anywhere” possible. You can compile
your Java program into byte codes on my platform that has a Java compiler. The byte
codes can then be run any implementation of the Java VM. For example, the same Java
program can run Windows NT, Solaris, and Macintosh.
Swing is a set of classes that provides more powerful and flexible components that
are possible with AWT. In addition to the familiar components, such as button
Dept of ISE, RLJIT 5
Java Program
Compilers
Interpreter
My Program
BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
checkboxes and labels, swing supplies several exciting additions, including tabbed panes,
scroll panes, trees and tables. Java2 The Complete Reference [6].
Applet is a dynamic and interactive program that can run inside a web page
displayed by a java capable browser such as hot java or Netscape [5].
CHAPTER 3
PROBLEM DESCRIPTION
Network asymmetry
Network asymmetry adversely affects routing in several different ways:
1) Connectivity: Asymmetric networks have fundamentally different connectivity than
bidirectional networks. Two nodes may be connected through one or more unidirectional
links requiring an alternative path in the reverse direction. Or worse, they may be
connected in only one direction with no route in the reverse direction. Ignoring the
unidirectional links, and routing solely on the bidirectional links, as many conventional
routing protocols do, mitigates the problem but may instead prevent several connected
nodes from communicating with each other.
2) Routing Protocols: Standard routing protocols often fail to function or function
inefficiently in an asymmetric network. Some routing protocols (e.g., TORA [12]) were
primarily designedfor bidirectional networks and hence break down in the presence of
unidirectional links. Several others (e.g., AODV [14]) function by avoiding the
unidirectional links and routing data only along the bidirectional links. A few other
protocols(e.g., DSR [8]) have the capability to include unidirectional links in their routes
through expensive mechanisms that provide significantly decreased throughput in
asymmetric networks.
3) Link-layer Services: In addition to the routing layer, unidirectional links also pose
several problems at the lower layers such as the data link and the MAC layers. Common
MAC-level schemes for congestion avoidance (RTS-CTS) and packet loss recovery
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BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
(ACKs) fail for unidirectional links. Moreover, other useful services such as detection of
link breaks and discovery of new neighbors provided by some MAC protocols become
unavailable to the routing protocols.
This paper first presents a simulation study to quantify the impact of asymmetry
on network connectivity and routing performance.
We model three different types of asymmetric networks based on the cause of
asymmetry:
(a) regular links becoming unidirectional due to random irregularities in signal
propagation,
(b) unidirectional links created by external noise sources, and
(c) nodes transmitting at different power.
Our study on asymmetry reveals several surprising insights about connectivity in
asymmetric networks. First, we find that routing solely on bidirectional links is highly
unreliable; while bidirectional connectivity can often be quite good, it may deteriorate
suddenly and cut-off several bidirectional routes leading to a poorly-connected network.
Second, a substantial percentage of unidirectional links have short (one to three hop)
paths connecting them in the reverse direction. Finally, inclusion of such unidirectional
links with short reverse paths significantly increases the stability of the routes and leads to
better connectivity overall, without significant overhead.
The key contribution of this paper is a framework to improve connectivity on
asymmetric networks and support off-the-shelf routing protocols. This framework,
called BRA, uses the in- sights mentioned above to provide a bidirectional abstraction of
the underlying asymmetric network to routing protocols.
BRA takes the approach of discovering and maintaining reverse paths for
unidirectional links. Its core is a novel algorithm called Reverse Distributed Bellman–
Ford Algorithm (RDBFA), which efficiently searches for reverse routes in a bounded
search region around each node.
BRA keeps the overhead of maintaining reverse routes low by dynamically
adjusting the size of the search region, and thereby the length of the reverse routes,
Dept of ISE, RLJIT 7
BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
independently at each node based on the prevailing extent of asymmetry around that
node.
BRA provides three critical functionalities to facilitate routing in asymmetric
networks. First, it improves connectivity between nodes by finding new or better routes
through unidirectional links. Second, it provides reverse-route forwarding for
unidirectional links, which makes them appear as bidirectional links. This abstraction
enables routing protocols to send control packets (such as notifications about discovered
routes and detected errors) in the reverse direction as it would on symmetric networks.
Finally, it implements critical functionalities that MAC and link layers are often
unable to provide in asymmetric networks; namely, recovery of lost packets sent across
unidirectional links, proactive detection of new neighbors, and notifications about failed
links.
BRA supports conventional off-the-shelf routing protocols with little or no
modifications. In this paper, we do not consider the details of integrating BRA within the
current protocol stack. Rather, we focus on the principles that are needed to provide such
an abstraction but we also provide a proof of concept: the implementation of the well-
known AODV routing protocol using BRA; other implementations can be carried out in a
similar manner.
Extensive evaluation of AODV layered on BRA shows that it obtains a significant
increase in the number of reachable destinations (double in some instances) in typical
asymmetric networks compared to regular AODV, which only routes using bidirectional
links. Moreover, the improved connectivity is obtained at a modest cost and little
difference in los rate and network delay.
Dept of ISE, RLJIT 8
BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
CHAPTER 4
SYSTEM ANALYSIS
System analysis can be defined, as a method that is determined to use the
resources, machine in the best manner and perform tasks to meet the information needs of
an organization.
4.1 System Requirement
Hardware specifications:
Processor : Intel Processor IV
RAM : 128 MB
Hard disk : 20 GB
Monitor : 15’ Samtron color
Keyboard : 108 mercury keyboard
Mouse : Logitech mouse
Software Specification:
Operating System – Windows XP/2000
Language used – J2sdk1.5.0
4.2 System Description
It is also a management technique that helps us in designing a new systems
or improving an existing system. The four basic elements in the system
development life cycle are
Analysis of the System
System Requirement
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BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
Design
Coding
Testing
Implementation
4.3 Existing Method
AODV Algorithm
The Ad hoc On Demand Distance Vector (AODV) routing algorithm is a routing
protocol designed for ad hoc mobile networks. AODV is capable of both unicast and
multicast routing. It is an on demand algorithm, meaning that it builds routes between
nodes only as desired by source nodes. It maintains these routes as long as they are
needed by the sources. Additionally, AODV forms trees which connect multicast group
members. The trees are composed of the group members and the nodes needed to connect
the members. AODV uses sequence numbers to ensure the freshness of routes. It is loop-
free, self-starting, and scales to large numbers of mobile nodes.
AODV builds routes using a route request / route reply query cycle. When a
source node desires a route to a destination for which it does not already have a route, it
broadcasts a route request (RREQ) packet across the network. Nodes receiving this
packet update their information for the source node and set up backwards pointers to the
source node in the route tables.
In addition to the source node's IP address, current sequence number, and
broadcast ID, the RREQ also contains the most recent sequence number for the
destination of which the source node is aware. A node receiving the RREQ may send a
route reply (RREP) if it is either the destination or if it has a route to the destination with
corresponding sequence number greater than or equal to that contained in the RREQ. If
this is the case, it unicast a RREP back to the source. Otherwise, it rebroadcasts the
RREQ. Nodes keep track of the RREQ's source IP address and broadcast ID. If they
receive a RREQ which they have already processed, they discard the RREQ and do not
forward it.
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BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
As the RREP propagates back to the source, nodes set up forward pointers to the
destination. Once the source node receives the RREP, it may begin to forward data
packets to the destination. If the source later receives a RREP containing a greater
sequence number or contains the same sequence number with a smaller hop count, it may
update its routing information for that destination and begin using the better route.
As long as the route remains active, it will continue to be maintained. A route is
considered active as long as there are data packets periodically travelling from the source
to the destination along that path. Once the source stops sending data packets, the links
will time out and eventually be deleted from the intermediate node routing tables. If a link
break occurs while the route is active, the node upstream of the break propagates a route
error (RERR) message to the source node to inform it of the now unreachable
destination(s). After receiving the RERR, if the source node still desires the route, it can
reinitiate route discovery.
4.4 Proposed System
This proposed system takes care of data transfer between computers of two
networks. Generally, during data transfer between pc of two different networks, a router
will be present in between the networks and it will take care of the scheduling of data
packets between the source and destination computers.
In the router there will be a number of ports and each port will take care of one
data transfer. In each port, there will be a queue for data packets and this is where
scheduling is applied. There are various scheduling algorithms possible to schedule the
packets in each port of the router. The objective of each router is to reduce the congestion
of data transfer.
Here we compare the proposed method with AODV (first-come-first-serve)
scheduling. We show the difference in terms of bandwidth at the router. The Bandwidth
will be kept in a stable condition and hence possibility of congestion and deadlock are
greatly reduced. The queue length is optimally adjusted using Bi-Directional Routing
Algorithm so that queue length is minimized during data transfer in order to keep the
bandwidth at a stable condition.
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BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
We will first select a certain number of inputs, say, x1, and x2 ... xn belonging to
the input space X. In the GA terminology, each input is called an organism or
chromosome. The set of chromosomes is designated as a colony or population.
Computation is done over epochs. In each epoch the colony will grow and evolve
according to specific rules reminiscent of biological evolution.
To each chromosome xi, we assign a fitness value which is nothing but f (xi).
Stronger individual that is those chromosomes with fitness values closer to the colony
optimal will have greater chance to survive across epochs and to reproduce than weaker
individuals which will tend to perish. In other words, the algorithm will tend to keep
inputs that are close to the optimal in the set of inputs being considered (the colony) and
discard those that under-perform the rest.
The crucial step in the algorithm is reproduction or breeding that occurs once per
epoch. The content of the two chromosomes participating in reproduction are literally
merged together to form a new chromosome that we call a child. This heuristic allows us
to possibly combine the best of both individuals to yield a better one (evolution).
During each epoch, a given fraction of the organisms is allowed to mutate. This
provides a degree of randomness which allows us to span the whole input space by
generating individuals with partly random genes.
Each epoch ends with the deaths of inapt organisms. We eliminate inputs
exhibiting bad performance compared to the overall group. This is based on the
assumption that they're less inclined to give birth to strong individuals since they have
poor quality genes and that therefore we can safely disregard them (selection).
Now that we've outlined the basic principles, let's examine in further detail how
this whole process is accomplished and how the algorithm works in practice. Let's take
the example of optimizing a function f over a space X.
Every input x in X is an integer vector x=(x1, x2... xn). For the sake of simplicity,
assume 0<=xi<=k for i=1...n. In order to implement our Bi-Directional Routing
Algorithm for optimizing f, we first need to encode each input into a chromosome. We
can do it by having log (k) bits per component and directly encoding the value xi (figure
Dept of ISE, RLJIT 12
BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
4.1). Each bit will be termed gene. Of course, we may choose any other encoding based
on our requirements and the problem at hand.
Figure 4.1 Encoding of input in to genes
At epoch 0, we generate (possibly randomly) an initial set of inputs in X. Then at
each epoch i, we perform fitness evaluation, reproduction, mutation and selection. The
algorithm stops when a specified criterion providing an estimate of convergence is
reached.
Reproduction: At each epoch, we choose a set of chromosomes belonging to the
population that will mate. We choose to call such individuals females. Each female
chooses a random set of potential partners and mates with the fittest of the group (this is
another way of achieving selection). Once two organisms have been chosen for crossover,
we merge their Bi-Directional information in order to create a new organism. The split
position is determined randomly.
Figure 4.2 Reproduction
Mutation: A new organism is created by randomly modifying some of its genes.
This can be done right after reproduction on the newly created child or as a separate
process.
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BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
Figure 4.3 Mutation
Death: Worst performers among the colony are given a high probability of dying
at the end of each epoch. We may also consider eliminating old chromosomes. The
highest performer is immune from death from old age.
Why do BRA Routing algorithm Work
Similarities among the strings with high fitness value suggest a relationship
between those similarities and good solutions.
A schema is a similarity template describing a subset of strings with similarities at
certain string positions.
Crossover leaves a schema unaffected if it doesn't cut the schema.
Mutation leaves a schema unaffected with high probability (since mutation has a
low probability).
Highly-fit, short schemas (called building blocks) are propagated from generation
to generation with high probability.
Competing schemata are replicated exponentially according to their fitness value.
Good schemata rapidly dominate bad ones.
The effectiveness of the search depends on the population size and the number of
generations.
The larger the population, the more likely that our initial population is
representative of the search space, and the more likely that a probabilistic survival of the
fittest mechanism produces the expected outcomes.
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BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
Each successive generation should improve the fitness of the result, so longer runs
usually produce better solutions.
Bi-Directional Routing Algorithm application level scheduling algorithm
generates the initial population, evaluates each individual’s fitness, and performs Bi-
Directional operations on the individuals with high fitness such copying, crossover and
mutation, to generate a new population. The Bi-Directional process continues with the
new population until a nearly optimal jobs assignment strategy is obtained. Finally, the
jobs are assigned to each node based on the strategy.
The connection to a resource is limited and a limited service is provided to the
jobs. The scheduling policies used are the greedy algorithm which assigns the resources
as and when it is found.
Suppose that there are three data servers {S1, S2, S3}, each having two available
connections. Let S1 have resources {r1, r2, r3, r4} and both S2 and S3 have resources
{r1, r2, r5, r6}. Suppose the scheduler has four tasks each processing one of the
resources. Each task with no contention, run for one hour. A greedy scheduler could
allocate the two connections of S1 for running the resources r1 and r2. The running time
is two hours as the other tasks cannot be run.
The parameters to be considered in job scheduling are the following
Total execution time is the time between the beginning of execution of the first job of
a series and completion of the last job.
Average turnaround time is the average, for each job from when the job arrives to
when the job finished.
Parallel BRA Routing algorithm PGA has the same advantage as a serial BRA
Routing algorithm, consisting in using representation of the problem parameters,
robustness, easy customization for a new problem and multiple solution capabilities. PGA
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BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
is usually faster, less prone to finding only sub-optimal solutions, and able of cooperating
with other search techniques in parallel. PGA can be divided into global, fine grained,
coarse grained and hybrid models.
The advantages of using PGA as stated in are
Parallel search from multiple points in a space
Works on a coding of the problem.
Can yield alternate solutions to the problem.
Better search even if no parallel hardware is used.
Higher efficiency and efficacy than sequential BRA Routing algorithms.
The global single population master slave Bi-Directional Routing Algorithm tells
the master stores the population, executes the Bi-Directional operators, and distributes
individuals to the slaves. The slave evaluates the fitness of the individual and reports the
fitness value to the master.
4.5 Algorithm design
We propose a model of the scheduling algorithm where the scheduler can learn
from the previous experiences.
We assume that the resource a job needs are in a location and not split over nodes.
Each node that has a resource runs a fixed number of jobs. This paper is limited to the
application level scheduling and does not discuss system level scheduling.
A type of parallel Bi-Directional Routing Algorithm is used called the Global
single population master slave BRA Routing algorithm. Selection and crossover are
considered in the entire population; each individual may compete and mate.
A binary encoding is used to convert the scheduling problem to chromosomes
and each chromosome has genes. Here the efficiency may be high if the same jobs have
to be scheduled.
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BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
The scheduler starts with no prior information about the jobs at first, after each
allocation the information is stored to the history base.
The next time the job of specific requirement comes a different combination is
tried according to the resource availability and if the execution time is lower then it is
recorded. This is called the learning phase.
If a new job which has not yet scheduled by the scheduler, then the system is put
to a brief learning phase again.
The encoding process is done by assuming that a chromosome has the following
gene structure.
Chromosome {gene1, gene2, gene3}
Gene1 is the job identifier.
Gene2 is the resource identifier.
Gene3 is the node identifier.
The fitness function f is the execution time of that job at the node. The population
generation is done by assigning binary set values for each of the genes.
Job A may be encoded as 00 and job B may be encoded as 01 and so on. The same
method can be used to represent all genes.
The sample population may have individuals like 00 01 10. After the population is
built in the learning phase, the fitness of the individual is recorded as the execution time
of the job at the node. The next time the same job is to be scheduled the history
information is checked and a new gene combination is found and job scheduled and the
fitness recorded. After time T the Bi-Directional operator of crossover is applied and the
individuals of the same job type are selected for crossover.
For example genes
00 01 | 10 20 ms
00 01 | 11 15 ms
The above representation says that job A which needed resource X has an
execution time of 20 ms in node n2 and 15 ms in node n3. The dotted lines indicate the
crossover point.
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BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
After cross over 00 01 11 15 ms. the parallel Bi-Directional Routing Algorithm is
used to evaluate in a way that the scheduler stores the population, executes Bi-Directional
operations and distributes individuals to the nodes. The nodes evaluate the fitness of the
individual.
The proposed algorithm is given below
Procedure for the learning phase
{
Create the population by encoding the problem.
Add chromosome to the history if it does not exist in the history
Else
Try a different combination of genes.
}
If job details available in history
Then
If the resource availability
Then send the job to the node
Else
Try a different resource if it is available.
Else
Initiate the learning procedure
After time T apply the Bi-Directional Operators on the history information.
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BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
CHAPTER 5
SYSTEM DESIGN
Design is concerned with identifying software components specifying
relationships among components. Specifying software structure and providing blue print
for the document phase.
Modularity is one of the desirable properties of large systems. It implies that the
system is divided into several parts. In such a manner, the interaction between parts is
minimal clearly specified.
Design will explain software components in detail. This will help the
implementation of the system. Moreover, this will guide the further changes in the system
to satisfy the future requirements.
5.1 Form design
Form is a tool with a message; it is the physical carrier of data or information.
The form is design in such a way that the simulated networks of computers connected
through router. The button is provided to invoke the network model. When this button is
clicked the two different networks are formed as Network 0 and network 1. In between
we have router.
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BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
Figure 5.1 form design
SWINGS:
Swing is a set of classes that provides more powerful and flexible components
than are possible with the AWT. In addition to that the familiar components such as
buttons, check box and labels swings supplies several exciting additions including tabbed
panes, scroll panes, trees and tables.
Even familiar components such as buttons have more capabilities in swing. For
example a button may have both an image and text string associated with it. Also the
image can be changed as the state of button changes.
Unlike AWT components swing components are not implemented by platform
specific code instead they are return entirely in JAVA and, therefore, are platform-
independent. The term lightweight is used to describe such elements. The number of
classes and interfaces in the swing packages is substantial.
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BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
SWINGS COMPONENT CLASSES:
JApplet - swing version of Applet, supports various “panes”. The add()
method of the container can be used to add a component to the content pane.
Void add(comp)
Here, comp is the component to be added to the content pane.
Object Hierarchy:
Component
+------Container
+------Panel
+------Applet
+------JApplet
JFrame- It is a Standard top level window with title bar, close, minimize,
maximize and restore buttons and a System menu.
Void add(comp)
Here,comp is the component to be added to the content pane.
Creating a Frame:
JFrame frmMain=new JFrame(strTitle);
Setting Parameters for Frame:
frmMain.setResizable(false);
frmMain.setBounds(frmLeft,frmTop,frmWidth,frmHeight);
frmMain.getContentPane().setLayout(null);
frmMain.setDefaultCloseOperation(EXIT_ON_CLOSE);
Object Hierarchy:
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BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
Component
+------Container
+------Panel
+------Applet
+------JApplet
+------JFrame
JLabel – It displays text and/or icon.
Details:
Jlabel(Icon i)
Is a constructor which labels the specified icon.
Void setText(String s)
Is a method that will give a name to the label as specified by user.
Creating a JLabel:
JLabel lblNodeCount=new JLabel("");
Void add(comp)
Here, comp is the component i.e. JLabel to be added to the content pane.
JLabel is added to the JFrame by the following Code:
frmMain.getContentPane().add(lblNodeCount);
Object Hierarchy:
Component
+------Container
+------Panel
+------Applet
+------JApplet
+------JFrame
+------JLabel
JButton- It provides a functionality of a push button.
Dept of ISE, RLJIT 22
BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
Figure 5.2 Jbutton for adding nodes
Details:
JButton(Icon icon)
JButton(String str)
JButton(String str,Icon icon)
Str and icon are string and icon used for button.
Creating JButton:
JButton btAddNodes=new JButton("Add Nodes");
Void add(comp)
Here, comp is the component i.e. JButton to be added to the content pane.
JButton is added to the JFrame by the following Code:
btAddNodes.setBounds(frmWidth-160-30,30,160,22);
btAddNodes.addActionListener(this);
frmMain.getContentPane().add(btAddNodes);
Object Hierarchy:
Component
+------Container
+------Panel
+------Applet
+------JApplet
+------JFrame
+------JButton
JScrollPane- JScrollpane is a lightweight container that automatically handles the
scrolling of another component. The component being scrolled can be an individual
component, such as a table or Jpanel.
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BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
Details:
JScrollPane(Component comp)
The component to be scrolled is specified by comp.
Creating ScrollPane:
JScrollPane spInput=new JScrollPane(txtInput);
Void add(comp)
Here, comp is the component i.e. JScrollPane to be added to the content
pane.
JScrollpane is added to the JFrame by the following Code:
spInput.setBounds(frmWidth-160-30,60,160,60);
spInput.setColumnHeaderView(new JLabel("Input:"));
frmMain.getContentPane().add(spInput);
Object Hierarchy:
Component
+------Container
+------Panel
+------Applet
+------JApplet
+------JFrame
+------JScrollPane
JTextField- JTextField is the simplest Swing text component. JTextField allows
to edit one line of text. It is derived from JTextComponent, which provides basic
functionality common to Swing text components.
Details:
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BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
JTextField(int cols)
JTextField(String str, int cols)
JTextField(String str)
Here str is the String to be initially presented and cols is the number of
columns in the text field.
Creating Text Field:
JTextField txtSourceDataSize=new JTextField("2048");
Void add(comp)
Here, comp is the component i.e. JTextField to be added to the content
pane.
JTextField is added to the JFrame by the following Code:
frmParameters.getContentPane().add(txtSourceDataSize);
Object Hierarchy:
Component
+------Container
+------Panel
+------Applet
+------JApplet
+------JFrame
+------JTextField
Now when you click the source and destination computer, the path between them
is drawn by invoking the algorithms called first Come First serve and Bi-Directional
Routing Algorithm for scheduling packet data transfer across the network.
The comparative study is also projected to the user, to check the efficiency of BRA
Routing algorithm.
Dept of ISE, RLJIT 25
BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
EVENT LISTENER Interfaces:
ACTION Listener-This interface defines actionperformed() method that is
invoked when an action event occurs.
void actionPerformed(ActionEvent ae)
This Listener is added to the frame by the following definition:
frmMain.addActionListener(this);
This Listener is invoked when Buttons ADD NODES, AODV or BRA is
Clicked.
Then actionPerformed method is invoked automatically.
MOUSELISTENER Interface-This interface defines five methods. If mouse
is pressed and released at the same point, mouseClicked() is invoked . When
mouse Enters a component, mouseEntered() method is invoked. When it
leaves mouseExited() is invoked. ThemosePressed() and mouseReleased()
is invoked when mouse is pressed and released respectively.
void mouseClicked(MouseEvent me)
void mouseEntered(MouseEvent me)
void mouseExited(MouseEvent me)
void mousePressed(MouseEvent me)
void mouseReleased(MouseEvent me)
mouseClicked() is invoked when mouse is clicked on one of the nodes in the
network.
MOUSEMOTIONLISTENER Interface-This interface defines two
methods.
The mouseDragged() method is invoked when mouse is dragged.
The mouseMoved() method is invoked when mouse is moved.
void mouseDragged(MouseEvent me)
void mouseMoved(MouseEvent me)Dept of ISE, RLJIT 26
BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
mouseMoved() is invoked when mouse is moved on the main frame.
5.2 Input design
Inaccurate input data is the most common case of errors in data processing.
Errors entered by data entry operators can control by input design.
Input design is the process of converting user-originated inputs to a computer-
based format. Input data are collected and organized into group of similar data.
Figure 5.3 input design
5.3 Module Design
Simulated Model:
The simulated model of network is constructed by keeping group of computer as
Network 0 and Network 1. In between the two network the router is placed from where
the data from one network flows to other network.
First Come First Serve Algorithm:
Dept of ISE, RLJIT 27
BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
The packet transfer between the networks in implemented using AODV
algorithm.
private void AODV(PathCollection tpaths)
{
int totalsize=Integer.parseInt(txtSourceDataSize.getText())*1024;
int speed=Integer.parseInt(txtLinkSpeed.getText())*1024;
int qlength=600; //cells (packets)
int packetlength=32; //one packet=32 bytes
int unitsize=packetlength*qlength,tbandwidth=0;
//determine data transfer speed
unitsize=(int)((double)speed*(1.0-(double)0.7));
long tstart=System.currentTimeMillis();
initializeGraph();
xmaxmain=(int)((double)totalsize/(double)unitsize);
for(int i=0,tindex=0;i<tpaths.size();i++)
{
Path tpath=tpaths.getPath(i);
int delivered=0;
while(delivered<totalsize)
{
for(int t=0;t<tpath.size();t++)
{
if(t>0)
{
int node1=tpath.getNode(t-1);
int node2=tpath.getNode(t);
g.setColor(new Color(255,0,0));
drawPath(node1,node2);
delivered+=unitsize;
if(delivered>=totalsize) break;
long tend=System.currentTimeMillis();
doubleseconds=((double)(tendtstart))/(double)1000;
Dept of ISE, RLJIT 28
BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
double trate=((double)delivered/(double)tseconds);
tbandwidth=(int)(trate/1024.0);
showDelivered(delivered,tbandwidth);
drawGraph(tindex,tbandwidth,0);
tindex+=1;
}
Globals.wait(Globals.DataTransferDelay);
}
showPaths(tpaths);
}
delivered=totalsize;
showDelivered(delivered,tbandwidth);
}
frmMain.setTitle(strTitle);
displayStatus();
}
Dept of ISE, RLJIT 29
BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
Figure 5.4 Output of AODV algorithm
BRA routing algorithm:
The packet transfer between the networks in implemented using BRA Routing
algorithm. The algorithm details were discussed in proposed system design.
private void BRA(PathCollection tpaths)
{
int totalsize=Integer.parseInt(txtSourceDataSize.getText())*1024;
int speed=Integer.parseInt(txtLinkSpeed.getText())*1024;
int qlength=600; //cells (packets)
int packetlength=32; //one packet=32 bytes
int unitsize=packetlength*qlength,tbandwidth=0;
//determine data transfer speed
unitsize=(int)((double)speed*(1.0-(double)0.85));
long tstart=System.currentTimeMillis();
initializeGraph();
xmaxmain=(int)((double)totalsize/(double)unitsize);
Dept of ISE, RLJIT 30
BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
for(int i=0,tindex=0;i<tpaths.size();i++)
{
Path tpath=tpaths.getPath(i);
int delivered=0;
while(delivered<totalsize)
{
for(int t=0;t<tpath.size();t++)
{
if(t>0)
{
int node1=tpath.getNode(t-1);
int node2=tpath.getNode(t);
g.setColor(new Color(255,0,0));
drawPath(node1,node2);
delivered+=unitsize;
if(delivered>=totalsize) break;
long tend=System.currentTimeMillis();
double tseconds=(double)(tendtstart)(double)100;
double trate= ((double)delivered/(double)tseconds);
tbandwidth=(int)(trate/1024.0);
showDelivered(delivered,tbandwidth);
drawGraph(tindex,tbandwidth,0);
tindex+=1;
}
Globals.wait(Globals.DataTransferDelay);
}
showPaths(tpaths);
}
delivered=totalsize;
showDelivered(delivered,tbandwidth);
}
frmMain.setTitle(strTitle);
displayStatus();
}
Dept of ISE, RLJIT 31
BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
Figure 5.5 Output of BRA algorithm
5.4 Project Result and Comparison:
Drawing the path between source and destination shows the data transfer between
the network of source and destination. For drawing the path, the points across the network
are also collected. The comparison of two algorithm result are displayed to the user in
separate frame to see the efficiency of BRA routing algorithm.
Figure 5.6 Comparison graph for AODV and BRA
Dept of ISE, RLJIT 32
BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
Figure 5.7 Status and Result for AODV and BRA algorithm
Dept of ISE, RLJIT 33
BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
5.5 Data Flow Diagram:
In this data flow diagram we are adding the nodes to the networks by clicking on
add nodes button and taking input parameters from parameter frame such as source data
size and link speed. After that nodes are added to the networks. Now we select the source
and destination nodes from each networks. Then we select any one of the algorithm such
as AODV or BRA for routing of packets from source to destination. Finally we will get
the status, result and comparison graph for the above algorithms.
Figure 5.8 Data flow diagram
Dept of ISE, RLJIT 34
ADD NODESINPUT PARAMETERS:SOURCE DATA SIZELINK SPEED
NETWORK1SELECT SOURCE / DESTINATION NODES
NETWORK 2SELECT SOURCE / DESTINATION NODES
AODVMODULE
BRA MODULE
STATUS:DELIVERED BYTESBANDWIDTH AT ROUTERRESULT:TIME TAKEN IN SECONDS
COMPARISION GRAPH FOR AODV AND BRA
BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
5.6 USE CASE DIAGRAM:
User selects source and destination nodes from both the networks. Here we use the
router to communicate between two networks for transmission of packets from source to
destination.
Figure 5.9 Use case diagram
Dept of ISE, RLJIT 35
NETWORK 1SOURCE/DESTINATION
ROUTER
NETWORK 2SOURCE/DESTINATION
BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
CHAPTER 6
IMPLEMENTATION AND TESTING
6.1 Implementation
Implementation includes all those activities that take place to convert from the old
system to the new. The new system may be totally new, replacing an existing system or it
may be major modification to the system currently put into use. This application
implemented with simulation model of computer network, constructed along with the
router.
The options are given to invoke the AODV and BRA Routing algorithm. The path
between source and destination were drawn and the result of both algorithms is discussed.
6.2 Software Testing
Software Testing is the process of confirming the functionality and correctness of
software by running it. Software testing is usually performed for one of two reasons:
1. Defect detection
2. Reliability estimation.
White box testing is concerned only with testing the software product; it cannot
guarantee that the complete specification has been implemented. White box testing is
testing against the implementation and will discover faults of commission, indicating that
part of the implementation is faulty.
Black box testing is concerned only with testing the specification; it cannot
guarantee that all parts of the implementation have been tested. Thus black box testing is
testing against the specification and will discover faults of omission, indicating that part
of the specification has not been fulfilled.
In order to fully test a software product both black and white box testing are required.
Dept of ISE, RLJIT 36
BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
The problem of applying software testing to defect detection is that software can
only suggest the presence of flaws, not their absence (unless the testing is exhaustive).
The problem of applying software testing to reliability estimation is that the input
distribution used for selecting test cases may be flawed. In both of these cases, the
mechanism used to determine whether program output is correct is often impossible to
develop. Obviously the benefit of the entire software testing process is highly dependent
on many different pieces. If any of these parts is faulty, the entire process is
compromised.
Software is now unique unlike other physical processes where inputs are received
and outputs are produced. Where software differs is in the manner in which it fails. Most
physical systems fail in a fixed (and reasonably small) set of ways. By contrast, software
can fail in many bizarre ways. Detecting all of the different failure modes for software is
generally infeasible.
The key to software testing is trying to find the myriad of failure modes –
something that requires exhaustively testing the code on all possible inputs. For most
programs, this is computationally infeasible. It is commonplace to attempt to test as many
of the syntactic features of the code as possible (within some set of resource constraints)
are called white box software testing technique. Techniques that do not consider the
code’s structure when test cases are selected are called black box technique.
Functional testing is a testing process that is black box in nature. It is aimed at
examine the overall functionality of the product. It usually includes testing of all the
interfaces and should therefore involve the clients in the process.
Final stage of the testing process should be System Testing. This type of test
involves examination of the whole computer system, all the software components, all the
hard ware components and any interfaces.The whole computer based system is checked
not only for validity but also to meet the objectives.
Dept of ISE, RLJIT 37
BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
CHAPTER 7
CONCLUSION
The proposed system is designed to implement the data transfer between the
computer networks by predictive job scheduling algorithm. The objective of keeping
router is to reduce the congestion of data transfer. The system compares the proposed
method with AODV scheduling. We show the difference in terms of bandwidth at the
router. Bandwidth will be kept in a stable condition and hence possibility of congestion
and deadlock are greatly reduced. The queue length is optimally adjusted using BRA so
that queue length is minimized during data transfer in order to keep the bandwidth at a
stable condition. Graph is also drawn to show the difference of bandwidth.
This project presents a bidirectional routing abstraction (BRA) to handle
unidirectional links that arise frequently in mobile ad hoc networks. BRA provides
routing protocols with the familiar bidirectional abstraction that they are typically
designed for and thus enables them to operate efficiently on asymmetric networks.
Internally, however, it actively uses both unidirectional and bidirectional links to 1) find
symmetric routes more effectively than conventional techniques; 2) find new, asymmetric
routes substantially increasing the reach ability of the network; and 3) find alternate
routes with shorter path length.
Finally, it showed through extensive evaluation how a typical routing protocol,
such as the well-known AODV, layered on BRA achieves superior connectivity in
asymmetric networks.
Dept of ISE, RLJIT 38
BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
APPENDIX A
ACRONYMS
AODV - Ad hoc On Demand Distance Vector
AWT - Abstract Window Toolkit
BRA - Bi-Directional Routing Abstraction
MAC - Media Access Control
PGA - Parallel Genetic Algorithm
RDBFA - Reverse Distributed Bellman-Ford Algorithm
RREP - Route Reply
RREQ - Route Request
RRER - Route Error
UDLR - Uni - Directional Link Routing
Dept of ISE, RLJIT 39
BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
APPENDIX- B
SCREEN SHOTS
This is the first screen we view after executing the project, next we are going to
show how to add the nodes to the networks.
MAIN FRAME
PARAMETERS FRAME
COMPARISON FRAME
Dept of ISE, RLJIT 40
BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
DISPLAYING THE NETWORK NODES
Here we are showing the nodes added to the networks.
Dept of ISE, RLJIT 41
BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
SELECTION OF SOURCE AND DESTINATION NODES
Here we will select source and destination nodes from both networks by left
clicking the node for source and right clicking the node for destination.
Dept of ISE, RLJIT 42
BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
PACKETS TRANSMISSION USING AODV ALGORITHM
After selecting the nodes we go for AODV algorithm to transmit the packets from
source to destination. The corresponding Status and Results are displayed for AODV
algorithm.
COMPARISION GRAPH FOR AODV ALGORITHM
The comparison graph shows the variation of Bandwidth at router for AODV algorithm.
Dept of ISE, RLJIT 43
BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
PACKETS TRANSMISSION USING BRA ALGORITHM
After selecting the nodes we go for BRA algorithm to transmit the packets from
source to destination. The corresponding Status and Results are displayed for BRA
algorithm.
COMPARISION GRAPH FOR BRA ALGORITHM
The comparison graph shows the variation of Bandwidth at router for BRA algorithm.
Dept of ISE, RLJIT 44
BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
MULTIPLE JOB SCHEDULING USING AODV ALGORITHM
Here we show the transmission of packets from multiple sources to multiple destinations.
Dept of ISE, RLJIT 45
BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
MULTIPLE JOB SCHEDULING USING BRA ALGORITHM
Here we show the transmission of packets from multiple sources to multiple destinations.
BIBILOGRAPHYDept of ISE, RLJIT 46
BIDIRECTIONAL ROUTING ABSTRACTION FOR ASYMMETRIC MOBILE ADHOC NETWORKS 2009-2010
[1] BRA: A Bidirectional Routing Abstraction for Asymmetric Mobile Ad Hoc
Network by Venugopalan Ramasubramanian and Daniel Mossé.
[2] S.Nesargi and R. Prakash, “A tunneling approach to routing with unidirectional
links in mobile ad hoc networks”.
[3] C. E. Perkins, E. M. Royer, and S. R. Das, “Ad-hoc on demand distance vector
(AODV) routing”.
[4] C. Cheng, R. Riley, S. Kumar, and J. Garcia-Lunes-Aceves, “A loopfree extended
Bellman-Ford routing protocol without bouncing effect”.
[5] The complete reference by Tim O'Brien, John Casey.
[6] JAVA 2 : The Complete Reference by Herbert Schildt.
Dept of ISE, RLJIT 47
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