Fundamental of WSN with Fault Tolerance Concepts

1. INITIAL SURVEY ON FAULT TOLERANCE
AND IMPLEMENTATION
IN WIRELESS SENSOR NETWORKS
PRESENTED BY:
Hitesh Mohapatra
Reg.No:1710040005
Supervised By:
Dr.(Prof.) A.K.Rath

2. CONTENTS:
 INTRODUCTION
 WSN
 FAULT
 FUNDAMENTAL OF FAULT TOLERANCE
 WHAT IS FAULT TOLERANCE
 WHY FAULT TOLERANCE
 SURVEY (Fault organising wireless sensor networks)
 Node Faults
 Network Faults
 Sink Faults
 Hardware Layer
 Software Layer
 Network Communication Layer
 Application Layer
 PREVENTIVE TECHNIQUE
 CURATIVE TECHNIQUE
 CONCLUSION
 REFERENCES
 QUESTIONS

3. INTRODUCTION
• Sensor networks are highly distributed networks of small, lightweight
wireless node, deployed in large numbers to monitor the environment
or system.
• Each node of the sensor networks consist of three subsystem:
• Sensor subsystem: senses the environment
• Processing subsystem: performs local computations on the sensed data
• Communication subsystem: responsible for message exchange with
neighboring sensor nodes
• The features of sensor nodes
• Limited sensing region, processing power, energy

4. PROPERTIES
• The advantage of sensor networks
• Robust : a large number of sensors
• Reliable :
• Accurate : sensor networks covering a wider region
• Fault-tolerant : many nodes are sensing the same event
• Two important operations in a sensor networks
• Data dissemination : the propagation of data/queries throughout the
network
• Data gathering : the collection of observed data from the individual sensor
nodes to a sink
• The different types of sensors
• Seismic, thermal, visual, infrared

5. APPLICATIONS OF SENSOR NETWORKS
• Using in military
• Battlefield surveillance and monitoring, guidance systems of intelligent
missiles, detection of attack by weapons of mass destruction such as
chemical, biological, or nuclear
• Using in nature
• Forest fire, flood detection, habitat exploration of animals
• Using in health
• Monitor the patient’s heart rate or blood pressure, and sent regularly to
alert the concerned doctor, provide patients a greater freedom of
movement

6. MORE APPLICATIONS
• Using in home (smart home)
• Sensor node can built into appliances at home, such as ovens, refrigerators,
and vacuum cleaners, which enable them to interact with each other and
be remote-controlled
• Using in office building
• Airflow and temperature of different parts of the building can be
automatically controlled
• Using in warehouse
• Improve their inventory control system by installing sensors on the
products to track their movement

7. ISSUES AND CHALLENGES IN
DESIGNING A SENSOR NETWORK
• Issues and Challenges
• Sensor nodes are randomly deployed and hence do not fit into any regular
topology. Once deployed, they usually do not require any human
intervention. Hence, the setup and maintenance of the network should be
entirely autonomous.
• Sensor networks are infrastructure-less. Therefore, all routing and
maintenance algorithms need to be distributed.
• Energy problem
• Hardware and software should be designed to conserve power
• Sensor nodes should be able to synchronize with each other in a
completely distributed manner, so that TDMA schedules can be imposed.
• A sensor network should also be capable of adapting to changing
connectivity due to the failure of nodes, or new nodes powering up. The
routing protocols should be able to dynamically include or avoid sensor
nodes in their paths.

8. CONT..
• Real-time communication over sensor networks must be supported
through provision of guarantees on maximum delay, minimum
bandwidth, or other QoS parameters.
• Provision must be made for secure communication over sensor
networks, especially for military applications which carry sensitive
data.

9. SENSOR NETWORK ARCHITECTURE
• The two basic kinds of sensor network architecture
• Layered Architecture
• Clustered Architecture

10. LAYERED ARCHITECTURE
• A layered architecture has a single powerful base station, and the layers
of sensor nodes around it correspond to the nodes that have the same
hop-count to the BS.
• In the in-building scenario, the BS acts an access point to a wired
network, and small nodes form a wireless backbone to provide wireless
connectivity.
• The advantage of a layered architecture is that each node is involved
only in short-distance, low-power transmissions to nodes of the
neighboring layers.

11. Figure : Layered architecture

12. CLUSTERED ARCHITECTURE
• A clustered architecture organizes the sensor nodes into clusters, each
governed by a cluster-head. The nodes in each cluster are involved in
message exchanges with their cluster-heads, and these heads send
message to a BS.
• Clustered architecture is useful for sensor networks because of its
inherent suitability for data fusion. The data gathered by all member of
the cluster can be fused at the cluster-head, and only the resulting
information needs to be communicated to the BS.
• The cluster formation and election of cluster-heads must be an
autonomous, distributed process.

13. Figure: Clustered architecture

14. INTRODUCTION to FAULT:
WHAT IS FAULT TOLERANCE
•Monitored and tolerated in order to provide a good
performance for the users throughout the network.
•WHY FAULT TOLERANCE
Reliability
Survivability
Performance

15. RELIABILITY:
• Our goal is to maximize the network reliability at its design
life.
• As dependence on mobile terminals increases, users will
demand the same system functionality, in terms of reliable
service.
• Reliability techniques comprise of the following phases.
• Fault confinement
• Fault detection
• Fault latency

16. SURVIVABILITY:
• Survivability is used to describe the available performance
of a network after a failure.
•Strategies to improve network survivability can be classified
into three categories:
-> Prevention,
-> Network design and capacity allocation,
->Traffic management and restoration.
•The ideal survivability goal is to make a network failure
imperceptible to the user by providing service continuity and
minimizing network congestion.

17. Survivability issues in wireless networks must take into account
these unique characteristics:
• user mobility,
• power conservation in mobile terminals,
• security (encryption and authentication),
• the poor quality of radio links (in comparison to wired
equivalents),
• channel capacity that is limited by a regulated frequency
spectrum.

18. PERFORMANCE
•Various issues and factors are considered for good performance of the
network. In order to achieve over all good performance of the network
fault tolerant techniques are implemented at various levels.
For example, Recovery
•Recovery is a process where the type of the faults is identified and new
clusters are allocated to the sensors.
•When the gateway is identified as failure all sensors in its clusters are
recovered.
•The status message is parsed to extract the identity of sensors that cannot
communicate with the gateway due to range faults in the gateways.
•Clustering is based on the distance between the sensors and gateways.
•During clustering each gateway creates a range set based on the
communication range of the sensors and the gateways.

19. TYPES OF CONCERNS IN FAULT TOLERANCES:
• Node Faults
• Network Faults
• Sink Faults
• Hardware Layer
• Software Layer
• Network Communication Layer
• Application Layer

20. PREVENTIVE TECHNIQUES
• This category includes all the techniques that attempt to prevent failure
by improving the use of the available resources and/or implementing
different alternatives that provide the same service in such a way that a
failure does not affect the continuity of the service.
• It can be distinguished in two level :
• Node Level
• Network Level

21. CURATIVE TECHNIQUE
• The techniques belonging to this class are triggered when a problem is
noticed in the network functioning.
• They attempt to recover the failure in order to resume the data sensing
and/or transmission.
• The recovery is done by replacing failed components by new ones.
There placement not means necessarily adding new components, but
activating redundant nodes which are in sleeping mode or relocating
some nodes to guarantee the service providing continuity.

22. SOME MORE CLASSIFICATION
• The second criterion for the classification of the
fault tolerance mechanisms is its main objective
when proposed. This criterion allows organizing the
mechanisms in four main classes:
• energy or power management
• flow management
• data management and coverage
• connectivity management

23. Fig.1. Classification of Fault Tolerance

24. CONCLUSION
Study of fault tolerance in each layer and different type of
implementations done to each layer and different algorithms proposed in
order to over come faults in the network.
Algorithm-based fault tolerance techniques can achieve high
performance, tolerate physical failures in the system, and still produce
correct results.

25. REFERENCES
• “A survey on fault tolerance in small and large scale wireless sensor networks”
Samira Chouikhi, Inès El Korbi, Yacine Ghamri-Doudane, Leila Azouz Saidane
Review article Computer Communications, Volume 69, 15 September 2015, Pages
22-37,Elsevier.
• “A survey on fault tolerance techniques in Wireless Sensor Networks” Gholamreza
Kakamanshadi; Savita Gupta; Sukhwinder Singh 2015 International Conference on
Green Computing and Internet of Things (ICGCIoT) Year: 2015 Pages: 168 – 173,IEEE
Conferences.
• “Neural fault isolator for Wireless Sensor Networks” Luciana Moreira Sa de
Souza; Ricardo Sangoi Padilha; Christian Decker 2008 5th International Conference
on Networked Sensing Systems Year: 2008 , Pages: 47 – 50,IEEE Conferences.
• Paradis, L. & Han, Q. J Netw Syst Manage (2007) 15: 171.
https://doi.org/10.1007/s10922-007-9062-0 DOIhttps://doi.org/10.1007/s10922-
007-9062-0 Publisher NameKluwer Academic Publishers-Plenum Publishers Print
ISSN1064-7570 Online ISSN1573-7705, Springer.
• Zhang Z., Shu L., Mehmood A., Yan L., Zhang Y. (2018) A Short Survey on Fault
Diagnosis in Wireless Sensor Networks. In: Huang M., Zhang Y., Jing W., Mehmood
A. (eds) Wireless Internet. WICON 2016. Lecture Notes of the Institute for
Computer Sciences, Social Informatics and Telecommunications Engineering, vol
214. Springer, Cham.
• Cheraghlou, M.N., Khadem-Zadeh, A. & Haghparast, M. Wireless Pers Commun
(2017) 92: 603. https://doi.org/10.1007/s11277-016-3559-3.

26. QUESTIONS FACED DURING
THE SURVEY

27. Q. What are the factors that lead to implementation of fault
tolerance in wireless networks in addition to two factors
reliability and internet that you have described at the
abstract level?
Additional factors that include for fault tolerant wireless
network is
a) Software
b) Hardware
c) Survivability
d) Performance
e) Heterogeneity of the network

28. Q. What are the different types of algorithms for
fault tolerance?
Distributed clustering algorithm
Topology controlling algorithm
Algorithm for improving the dependability

29. Top Journals in this area
• IEEE, Wireless Communication ,
http://www.comsoc.org/wirelessmag
• ACM Computing Surveys http://surveys.acm.org/
• Mobile Networks and Applications
http://www.springer.com/engineering/signals/journal/11
036
• IEEE Transactions on Communications
http://www.comsoc.org/tc
• IEEE Communications Surveys and Tutorials
http://www.comsoc.org/cst
• Computer Communications The International Journal for the
Computer and Telecommunications Industry
https://www.journals.elsevier.com/computer-
communications

30. Thank You
QUESTIONS?