UNIVERSITY OF LAY ADVENTISTS OF KIGALI
(UNILAK)
Faculty: Computing and Information Sciences (CIS)
Module: Wireless Communication System
Topic: Mobile Ad-hoc Networks
Submitted To: Dr. Djuma Sumbiri
Submitted By: Group Four (4)
Group Members:
1. Jonah K. Menson ………………… 18073/2021
2. James B. Gibson …………………. 18213/2021
3. Lee Geyarlee ……………………… 18440/2021
4. Jonathan O. Grigsby Jr. ...……...…. 18103/2021
5. John Dolly ………………………… 18785/2021
6. Bleato Karnga …………….….….... 16700/2020
7. Uhuo Uchenna………….…………. 16801-2020
8. Uwase Celine ……………………... 15954/2019
Submission Date: May 28, 2023
Introduction
Mobile Ad-hoc Network (MANET):
Mobile Ad hoc Networks (MANETs) are self-configuring, infrastructure-less networks consisting
of mobile devices (nodes) that communicate with each other without the need for a centralized
infrastructure such as routers or access points. In a MANET, each node can act as both a transmitter
and a receiver, and the network topology can change dynamically as nodes move around, join or
leave the network.
Each device in a MANET is free to move independently in any direction and will therefore change
its links to other devices frequently.
CHARACTERISTICS OF MANET
1. In MANET, each node acts as both host and router. That is, it is autonomous in behavior.
2. The nodes can join or leave the network anytime, making the network topology dynamic
in nature.
3. Mobile nodes are characterized with less memory, power and light weight features.
4. All nodes have identical features with similar responsibilities and capabilities and hence it
forms a completely symmetric environment.
5. When a source node and destination node for a message is out of the radio range, the
MANETs are capable of multi-hop routing.
DIAGRAM OF A MOBILE AD-HOC NETWORK
TYPES OF MANETs
1. Vehicular ad-hoc networks (VANETs):
VANETs are used for communication between vehicles and roadside equipment.
Vehicular Ad-Hoc Networks (VANETs) play a crucial role in enhancing road safety and
mitigating accidents or collisions.
DIAGRAM TWO OF VANETs
2. Smart phone ad-hoc networks (SPANs)
Smartphone Ad-Hoc Networks (SPANs) are wireless communication networks formed by
smartphones or other mobile devices without relying on a centralized infrastructure, such
as cellular towers or Wi-Fi access points.
3. Internet-based mobile ad-hoc networks (iMANETs):
iMANETs are ad-hoc networks that link mobile nodes and fixed Internet-gateway nodes.
For example, multiple sub-MANETs may be connected in a classic Hub-Spoken VPN to
create a geographically distributed MANET.
PROS OF MANET
1. Scalable: MANETs are scalable because a greater number of nodes can be formed.
2. The network can be set up at any place and time
3. Less expensive as compared to wired network.
4. They provide access to inform and services regardless of geographic position.
CHALLENGES OF MANET
1. The wireless link characteristics are time-varying in nature
i.e.: There are transmission impediments like fading, path loss, blockage and interference
that adds to the susceptible behavior of wireless channels.
2. Limited range of wireless transmission
i.e.: The data rates are low when compared to wireless networks
3. Packet losses due to errors in transmission
i.e.: MANETs experience higher packet loss due to factors such as hidden terminals that
results in collisions, interference, frequent breakage in paths caused by mobility of nodes,
increased collisions due to the presence of hidden terminals problems.
4. Frequent networks partitions
The random movement of nodes often leads to partition of the network. This mostly affects
the intermediate nodes.
5. Limitations of Mobile Nodes
The mobile nodes have short battery life.
Characteristics of MANET cont…
i.
Dynamic Topologies: Network topology which is typically multihop may change
randomly and rapidly with time, it can form unidirectional or bi-directional links.
ii.
Bandwidth constrained, variable capacity links: Wireless links usually have lower
reliability, efficiency, stability, and capacity as compared to a wired network
iii.
Autonomous Behavior: Each node can act as a host and router, which shows its
autonomous behavior.
iv.
Energy Constrained Operation: As some or all the nodes rely on batteries or other
exhaustible means for their energy. Mobile nodes are characterized by less memory,
power, and lightweight features.
v.
Limited Security: Wireless networks are more prone to security threats. A centralized
firewall is absent due to the distributed nature of the operation for security, routing, and
host configuration.
vi.
Less Human Intervention: They require minimum human intervention to configure the
network, therefore they are dynamically autonomous in nature.
Advantages:
i.
Flexibility: MANETs are highly flexible, as they can be easily deployed in various
environments and can be adapted to different applications and scenarios. This makes
them ideal for use in emergency situations or military operations, where there may not be
a pre-existing network infrastructure.
ii.
Scalability: MANETs can easily scale to accommodate a large number of nodes, making
them suitable for large-scale deployments. They can also handle dynamic changes in
network topology, such as the addition or removal of nodes.
iii.
Cost-effective: Since MANETs do not require any centralized infrastructure, they are
often more cost-effective than traditional wired or wireless networks. They can also be
used to extend the range of existing networks without the need for additional
infrastructure.
iv.
Rapid Deployment: MANETs can be rapidly deployed in areas where infrastructure is
not available, such as disaster zones or rural areas.
Disadvantages:
i.
Security: MANETs are vulnerable to security threats, such as attacks by malicious
nodes, eavesdropping, and data interception. Since the network is decentralized, there is
no central authority to ensure the security of the network.
ii.
Reliability: MANETs are less reliable than traditional networks, as they are subject to
interference, signal attenuation, and other environmental factors that can affect the quality
of the connection.
iii.
Bandwidth: Since MANETs rely on wireless communication, bandwidth can be limited.
This can lead to congestion and delays, particularly when multiple nodes are competing
for the same channel.
iv.
Routing: Routing in MANETs can be complex, particularly when dealing with dynamic
network topologies. This can result in inefficient routing and longer delays in data
transmission.
v.
Power Consumption: Since MANETs rely on battery-powered devices, power
consumption can be a significant issue. Nodes may need to conserve power to extend the
life of the battery, which can limit the amount of data that can be transmitted.
APPLICATIONS OF MANET
1. Military
Mobile Ad-hoc Network would allow the military to take advantage of technology to
maintain an information network between the soldiers, vehicles, and military information
headquarters.
2. Rescue Operation
Ad-hoc can be used in emergency or rescue operations for disaster relief efforts, e.g., in
fire, flood, or earthquake.
3. Business Work
Whenever any emergency meeting is planned outside the office exchange of information
on a given project is made possible by means of MANET.
4. Classroom and Conference
Mobile Ad-hoc networks can autonomously link an instant and temporary multimedia
network using notebook computers to spread and share information among participants.
Example, conference or classroom.
THE THREE TYPES OF MANETs
1. Vehicular Ad-Hoc Networks (VANETs):
Vehicular Ad-Hoc Networks (VANETs) play a crucial role in enhancing road safety and mitigating
accidents or collisions. Here are some ways in which VANETs can help:
i.
Collision Warning Systems: VANETs enable vehicles to communicate with each other
and exchange information in real-time. This communication can be utilized to develop
collision warning systems. For example, if a vehicle detects a potential collision with
another vehicle ahead, it can transmit a warning message to nearby vehicles, alerting them
to the danger and allowing them to take appropriate actions, such as braking or changing
lanes.
ii.
Emergency Vehicle Notification: VANETs facilitate the quick dissemination of
information about emergency vehicles, such as ambulances, police cars, or fire trucks.
When an emergency vehicle is approaching, it can transmit a signal to nearby vehicles,
notifying them of its presence and requesting the right of way. This helps in clearing a path
for the emergency vehicle, reducing response times, and potentially saving lives.
iii.
Traffic Congestion Management: VANETs enable vehicles to share information about
traffic conditions, such as congestion, accidents, or road closures, with other vehicles in
the network. This information can be used to dynamically adjust routes and redirect
vehicles to less congested paths, reducing the likelihood of accidents caused by heavy
traffic or gridlock situations.
iv.
Intersection Safety: Intersections are often high-risk areas for accidents. VANETs can
enhance intersection safety by enabling vehicles to communicate their positions, speed,
and intentions to other vehicles approaching the intersection. This information can be used
to coordinate traffic signals and optimize the timing of traffic lights, improving traffic flow
and reducing the likelihood of collisions.
v.
Pedestrian Safety: VANETs can also enhance pedestrian safety by enabling vehicles and
pedestrians to communicate with each other. For example, a pedestrian equipped with a
mobile device can transmit their presence and location information to nearby vehicles.
Vehicles can then use this information to detect pedestrians in their vicinity and take
appropriate actions to avoid accidents, such as sounding an alert or applying automatic
emergency braking.
2. Smartphone Ad-Hoc Networks (SPANs):
Smartphone Ad-Hoc Networks (SPANs) are wireless communication networks formed by
smartphones or other mobile devices without relying on a centralized infrastructure, such as
cellular towers or Wi-Fi access points. SPANs leverage the built-in wireless capabilities of
smartphones to establish direct peer-to-peer connections and enable communication between
devices within close proximity. Here are some key aspects of SPANs:
i.
Formation of Networks: SPANs allow smartphones to form temporary networks on the
fly, without the need for an existing infrastructure. This can be achieved using various
wireless communication technologies such as Bluetooth, Wi-Fi Direct, or ad-hoc
networking protocols. When smartphones come into range of each other, they can
automatically discover and connect to form a network.
ii.
Decentralized Communication: In SPANs, devices communicate directly with each other
without relying on a centralized server or network infrastructure. Each smartphone acts as
both a client and a router, relaying messages to other devices within range. This
decentralized communication allows for efficient and flexible data exchange in scenarios
where traditional networks may be unavailable or unreliable.
iii.
Peer-to-Peer Applications: SPANs enable a range of peer-to-peer applications, allowing
smartphones to share resources and services directly. For example, users can share files,
exchange messages, play multiplayer games, or collaborate on tasks without requiring an
internet connection. SPANs provide a convenient means of communication and resource
sharing in environments with limited or intermittent network connectivity.
iv.
Emergency Communication: SPANs can be particularly valuable in emergency situations
where existing communication infrastructure may be disrupted. During natural disasters or
emergencies, when cellular networks may be congested or damaged, SPANs can help
establish communication among nearby devices, enabling users to send distress signals,
coordinate rescue efforts, or share critical information.
v.
Proximity-based Services: SPANs can facilitate proximity-based services, where
smartphones can discover and interact with other devices or services in their immediate
vicinity. For example, SPANs can support location-based social networking, allowing users
to find and connect with nearby friends or discover local businesses and services.
3. Internet-based Mobile Ad-hoc Networks (iMANETs)
Internet-based Mobile Ad-Hoc Networks (iMANETs) are wireless networks that combine the
principles of Mobile Ad-Hoc Networks (MANETs) with the connectivity and services provided by
the Internet. iMANETs enable mobile devices to form ad-hoc networks and establish
communication links using the existing Internet infrastructure.
Here are some key aspects of iMANETs:
i.
Hybrid Network Architecture: iMANETs combine the decentralized nature of MANETs
with the global connectivity of the Internet. Mobile devices, such as smartphones or tablets,
form ad-hoc networks among themselves using wireless communication technologies like
Wi-Fi or Bluetooth. These ad-hoc networks are then connected to the Internet through
gateways or access points, allowing communication beyond the immediate range of
devices.
ii.
Internet Connectivity: The integration of the Internet in iMANETs provides access to a
wide range of online services and resources. Devices within the ad-hoc network can
connect to the Internet through gateways, enabling them to access websites, send emails,
use cloud services, and utilize other online applications. This connectivity expands the
capabilities of the ad-hoc network beyond local communication and enables interaction
with the global Internet ecosystem.
iii.
Routing and Communication: iMANETs utilize routing protocols that facilitate
communication within the ad-hoc network as well as between the ad-hoc network and the
Internet. Routing protocols dynamically determine the optimal paths for data transmission,
considering factors like device mobility, network congestion, and the availability of
Internet gateways. These protocols ensure efficient and reliable communication, both
within the ad-hoc network and with external Internet resources.
iv.
Service Discovery and Integration: iMANETs support service discovery mechanisms
that allow devices to identify and utilize services available within the network or on the
Internet. Devices can discover and interact with other devices, access shared resources, or
utilize online services and applications. Service discovery protocols help in locating and
integrating various services, fostering collaboration and resource sharing among devices in
the network.
v.
Mobility Support: iMANETs handle device mobility by adapting routing and
communication mechanisms to accommodate dynamic changes in network topology. As
devices move within or between ad-hoc networks, routing protocols adjust to establish new
paths and maintain connectivity. The integration with the Internet allows seamless
communication even when devices transition between local ad-hoc networks and external
Internet connections.
Conclusion
Mobile ad hoc network can also be termed as a wireless ad hoc network (MANET or WANET). It
is a decentralized type of wireless network. The network is ad hoc because it does not rely on a
pre-existing infrastructure, such as routers or wireless access points. Instead, each node participates
in routing by forwarding data for other nodes.
References:
1. Ad Hoc Mobile Wireless Networks: Principles, Protocols, and Applications"
Authors: C.K. Toh
Publisher: Pearson Education
Year: 2002
ISBN: 020178456X
Link: Amazon
2. Mobile Ad Hoc Networking: Cutting Edge Directions"
Editors: Stefano Basagni, Marco Conti, Silvia Giordano, Ivan Stojmenovic
Publisher: John Wiley & Sons
Year: 2013
ISBN: 978-0470740632
Link: Wiley
3. Routing in Mobile Ad Hoc Networks: A Survey"
Authors: Elizabeth M. Royer, Chai-Keong Toh
Journal: IEEE Communications Magazine
Year: 1999
Volume: 39
Issue: 2
Pages: 90-100
Link: IEEE Xplore
4. TSecurity in Mobile Ad Hoc Networks: Challenges and Solutions"
Authors: Huiping Guo, Yingshu Li
Journal: IEEE Wireless Communications
Year: 2009
Volume: 16
Issue: 1
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Link: IEEE Xplore
5. Performance Comparison and Analysis of MANET Routing Protocols"
Authors: R.S. Rajesh, C. Puttamadappa
Journal: International Journal of Computer Applications
Year: 2010
Volume: 8
Issue: 10
Pages: 18-24
Link: ResearchGate