Delivered Guest Talk in Faculty Development Programme held on 27th July 2017 @BVICAM New Delhi
1. Adhoc Networks & its Related
Empirical Research Directions
Institute of Technology & Science
• Computer Network is an interconnected
collection of independent computers which aids
• Good Communication Medium
– Sharing of Available resources
– Improved reliability of services
– Cost effectiveness
• Two major components
– Distributed Applications
– Networking Infrastructure
3. Wireless Network in Brief
• Computer networks that are not connected by
wires(Cables, Fibers etc.)of any kind.
• It enables enterprises to avoid the costly
process of introducing cables into buildings or
as a connection between different equipment
• The basis of wireless systems are radio waves,
an implementation that takes place at the
physical level of network structure.
4. WIRELESS NETWORKS DIVISION
• Industry to develop, deploy, and promote
emerging technologies and standards that will
dramatically improve the operation and use of
6. Cellular Networks
• Network is distributed over land areas called cells,
each served by at least one fixed-location transceiver,
known as a cell site or base station.
• This base station provides the cell with the network
coverage which can be used for transmission of
voice, data and others.
• A cell might use a different set of frequencies from
neighboring cells, to avoid interference and provide
guaranteed service quality within each cell.
7. Wireless Sensor Network
• It is collection of nodes, where each node is connected to one
(or sometimes several) sensors.
• Sensor network node consist of: a radio transceiver with an
antenna , a microcontroller, an electronic circuit for
interfacing with the sensors and an energy source, usually
a battery .
8. Wireless Mesh Network
• Rich interconnection among devices or nodes.
• consist of mesh clients, mesh routers and gateways.
• Mobility of nodes is less frequent. In case of high,
more time consumption in updating routes rather
than Data Delivery.
• Low-mobility centralized form of wireless ad hoc
MANET – Mobile Ad hoc Networks
Mobile ad hoc network is “a transitory association [1-9] of mobile
nodes which do not depend upon any fixed support infrastructure.
Connection and disconnection is controlled by the distance among
nodes and by willingness to collaborate in the formation of cohesive,
albeit transitory community.”
Communication is done through wireless links among mobile hosts
through their antennas.
11. MANET – Mobile Ad hoc Networks
- Mobility - Self Forming and healing - No Infrastructure
- Highly Dynamic - Independent of public infrastructure - Peer to Peer
Paradigm of Mobile ad hoc networks
• Formation of Dynamic Topology
• Bandwidth Constraints
• Energy Constrained Operation
• Limited Physical Security
• Autonomous transitory association of mobile nodes
• Possibly uni-directional links
• Constrained resources like Battery power, wireless transmitter range
• Network partitions due to frequent node movement
Establishing communication for emergency or
rescue operations, disaster relief efforts and
Mobility & Traffic
13. Applications of MANETs
Collaborative & Distributive Computing
Search & Rescue
Sensor Based Applications
16. Difference between WSN and MANETs
Communicating and Processing
Part “No Sensing Part”
Size Small Larger
Small Batteries Large Batteries
Cost Cheaper Expensive Comparatively
Density High Low
Redundancy High Low
Resources Limited like Memory
Big Memory Size
Higher Processing Capability
“To find and maintain routes between
nodes in a dynamic topology with
possibly uni-directional links, using
• Each node in this network must be able to
take care of routing of the packets and this is
the domain of ad-hoc routing. In routing
process, a route between source and
destination may consist of two or more
• Route finding and maintenance is very
crucial problem due to rapid changes in
• Ad hoc routing protocols make routing
decisions based on individual node mobility .
Kinds of Routing
TABLE DRIVEN ROUTING
DSDV routing* (CGSR)
ON DEMAND ROUTING
TORA (multi-path) (hybrid)
Zone Routing Protocol
Geographical Routing (LB)
18. Research Issues in MANETs(1)
• The MAC protocol design should be fully
distributed involving minimum control over
head, synchronization(Usage of scarce
resources such as bandwidth & battery
• MAC protocol should be able to overcome
the effect of collisions due to Hidden Terminal
Problem, Control Packets used for
synchronization., exposed terminal problem.
Designing Issues in MANETs
19. Research Issues in MANETs(2)
• Mechanism should attempt to minimize the
• Ability to provide an equal or weighted share
of the bandwidth to all computing nodes.
• Mechanism for throughput enhancement
– Minimize the occurrence of collisions
– Maximize Channel Utilization
– Minimizing Control Overhead
Designing Issues in MANETs
21. Research Issues in MANETs
•Medium Access Scheme
•Real Time Traffic Transport
•Ability to measure resource
•Capability for power
•Use of Directional
• Bandwidth Constraint
• Error Prone and Shared Channel
• Location dependent Contention
• Resource Constraint
Battery Power, Buffer Storage
Characteristics for Efficient Routing
Quick Route Reconfiguration
Loop Free Routing
Distributed Routing Approaches
Minimal Control Overhead
Security & Privacy
Support for Time sensitive Traffic
QoS (Jitter, Delay, Bandwidth, PDR, Throughput)
oriented TCP Protocol
•Security (Attacks, Resource
Consumption, Information Disclosure, Host
• In ad hoc networks, requirement of efficient routing has
been a complex problem due to lack of fixed infrastructure.
• The mobility of ad hoc nodes in routing imposes limitations
on their power capacity, bandwidth, as well as their
• Performance evaluation of ad hoc routing protocols based on
routing metrics is another challenging issue.
23. Research Problems(Still Unexplored)
• Current simulation use fixed environment, where as real life
situations are practically random in nature.
• To study various mobility model to create random scenarios.
• Requirement of effective and efficient mobility management with
respect to specific application.
• Develop routing protocol which will consider the concept of power
as one of deciding factor in route selection.
• Develop a security solution that is embedded into possibly every
component in the network.
• To explore methods to optimally manage resources.
• Develop routing protocol which will evaluate presence of nodes in
static as well as dynamic scenario.
25. VANETs(Vehicular Adhoc Networks)
• Subclass of MANETs
• to provide communications
among nearby vehicles and
between vehicles and nearby
• Needs road related
information in advance for
and sensing capabilities.
Figure 1 VANETs system domains
28. Research Problems(Still Unexplored)
• Securing network transmissions without
securing the routing protocols is not sufficient.
Therefore, in VANET network with security
needs, there must be two security systems:
• One to protect the data transmission.
• One to make the routing protocol secure.
• Unmanned Air Vehicles
• Driverless Aircraft
• Remote Control by human operator or
• Collection of Sensors, Actuators, Computing
Power, Communication Link, Remote Control-
Data Link, Recorder, Energy Supply
31. Flying Adhoc Networks
• It is group of Unmanned Air Vehicle(UAV) is
communicating with each other with no need to
access point, but at least one of them must be
connected to a ground base or satellite.
• Like as Autopilot.
• Known as Air bone Adhoc Networks.
• Reliable Protocol
– Two Factors
• Mobility Model
• Traffic Pattern
• FANETs are new form of MANETs in which the
nodes are UAVs.
• Single UAV Systems cannot form a FANET
which is valid only for Multi UAV Systems.
• The UAV Communication must be realized
with the help of an ad hoc network between
UAVs then it will form FANETs.
• E.g. Aerial Robot Team, Aerial Sensor Network
38. Research Issues in FANETs
• Routing: Existing MANETs routing protocols do not
satisfy the FANET requirements.
• There is need to develop New routing algorithm that
can support peer to peer communication and traffic
management which is still an open issue.
• There is need to develop Reliable environment in
• Due to transmission of fast sender and multiple
sender, the receiver may be overloaded. So Flow
control is an important issue for heterogeneous
39. Research Issues in FANETs
• There is need to develop efficient transport
layer protocol which needs to fulfill
multimedia application reliability
requirements including its performance based
requirements(Delay, Bandwidth, jitter etc.).
• There is need to refine Mobility Models as
per FANET requirements.
42. Simulator & Emulator
• A Simulator is a less complex application that
simulation internal behavior of a device, but
does not emulate hardware and does not
work over the real operating System.
• An Emulator is an application the emulates
real mobile device software, hardware and
operating systems allowing us to test and
debug our application.
• Complex network topologies
• Gigabit speeds
• Scalable Architecture for Real Time Experiments
• Open source and free
• Marionnet is a virtual network laboratory: it allows
users to define, configure and run complex computer
networks without any need for physical setup.
• GNU/Linux host machine is required to simulate a
whole Ethernet network complete with computers,
routers, hubs, switches, cables, and more.
• Support is also provided for integrating the virtual
network with the physical host network.
• Software Defined Networking technologies.
• Mininet is most useful to researchers who are
building SDN controllers and need a tool to
verify the behavior and performance of SDN
• Knowledge of the Python scripting language is
very useful when using Mininet.
• Excellent documentation
• Command-line based simulation tool that uses
user-mode Linux to create the virtual machines.
• A full Linux OS can run on each machine.
• It has good documentation and the project’s web
site has a long list of interesting lab scenarios to
practice, with documentation for each scenario.
• It also appears to be actively supported by a small
community and was last updated in 2011.
• It is a discrete-event open-source network
simulator for Internet systems, used primarily
for research and educational use. NS-3 is a
complex tool that runs simulations described by
code created by users, so you may need
programming skills to use it.
• NS-3 can run real software on simulated nodes
using its Direct Code Execution feature.
• This allows researchers to test real software in a
discrete-event network simulation to produce
• It is a new software-defined network (SDN)
emulator that offers functionality similar to
the Mininet network emulator and adds some
useful tools for generating traffic and
monitoring Open Flow messages and
evaluating SDN controller performance.