fault management in mobile ad-hoc networks by tridib mukherjee
TRANSCRIPT
![Page 1: Fault Management in Mobile Ad-Hoc Networks by Tridib Mukherjee](https://reader035.vdocuments.site/reader035/viewer/2022070418/5697bfde1a28abf838cb2581/html5/thumbnails/1.jpg)
Fault Management in Mobile Ad-Hoc Networks
by Tridib Mukherjee
![Page 2: Fault Management in Mobile Ad-Hoc Networks by Tridib Mukherjee](https://reader035.vdocuments.site/reader035/viewer/2022070418/5697bfde1a28abf838cb2581/html5/thumbnails/2.jpg)
Transient Faults in Mobile Ad-Hoc Networks
Mobility of the NodesError Prone MediumLink FailuresLow Battery PowerNode Corruption
![Page 3: Fault Management in Mobile Ad-Hoc Networks by Tridib Mukherjee](https://reader035.vdocuments.site/reader035/viewer/2022070418/5697bfde1a28abf838cb2581/html5/thumbnails/3.jpg)
Fault Tolerance
Ability of a system to perform its function correctly even in the presence of internal faults.
Makes the network system more dependable.
Hides the faults from the user.Two basic kinds of Fault Tolerance :
Proactive and Reactive.
![Page 4: Fault Management in Mobile Ad-Hoc Networks by Tridib Mukherjee](https://reader035.vdocuments.site/reader035/viewer/2022070418/5697bfde1a28abf838cb2581/html5/thumbnails/4.jpg)
Self Stabilization
Stabilizes a Distributed System to a legitimate state from any arbitrary initial state.
Used as a Proactive Fault Tolerant Scheme.
There are 2 properties : Closure and Convergence.
![Page 5: Fault Management in Mobile Ad-Hoc Networks by Tridib Mukherjee](https://reader035.vdocuments.site/reader035/viewer/2022070418/5697bfde1a28abf838cb2581/html5/thumbnails/5.jpg)
Self-stabilizing Multicast Routing Protocols For Mobile Ad-Hoc Networks
Shortest Path Spanning Tree (SPST)Used in this project
Maintains Shortest Path from source to destination.
Beacon Messages provide information about neighbors.
Recreates the tree in case of faults.Unnecessarily propagates limited faults
across the network.
![Page 6: Fault Management in Mobile Ad-Hoc Networks by Tridib Mukherjee](https://reader035.vdocuments.site/reader035/viewer/2022070418/5697bfde1a28abf838cb2581/html5/thumbnails/6.jpg)
Fault Containment
Contains the fault in the region where it has occurred
Improves stabilization time Considerably.Increases Computational and
Communication Overhead.Does not contain faults in all the desired
cases in Mobile Ad-Hoc Networks.Tradeoff needed for optimal Energy
Efficiency while managing the faults.
![Page 7: Fault Management in Mobile Ad-Hoc Networks by Tridib Mukherjee](https://reader035.vdocuments.site/reader035/viewer/2022070418/5697bfde1a28abf838cb2581/html5/thumbnails/7.jpg)
Fault-containment Algo.
can_stabilize :
![Page 8: Fault Management in Mobile Ad-Hoc Networks by Tridib Mukherjee](https://reader035.vdocuments.site/reader035/viewer/2022070418/5697bfde1a28abf838cb2581/html5/thumbnails/8.jpg)
Propose for Adaptation
Adapt to the changing Fault Scenarios.Use Self Stabilization where Fault
Containment can not contain the faults.Use Fault Containment where it can
contain the faults.
![Page 9: Fault Management in Mobile Ad-Hoc Networks by Tridib Mukherjee](https://reader035.vdocuments.site/reader035/viewer/2022070418/5697bfde1a28abf838cb2581/html5/thumbnails/9.jpg)
Fault Classification
Fault-Containable (FC) Faults Fault can be contained using Fault Containment
Non-Fault-Containable (NFC) Faults Fault Containment can not contain the faults Self-stabilization and Fault-containment have same
performance Fault-containment executes self-stabilization
internally Fault-containment adds computational overhead
![Page 10: Fault Management in Mobile Ad-Hoc Networks by Tridib Mukherjee](https://reader035.vdocuments.site/reader035/viewer/2022070418/5697bfde1a28abf838cb2581/html5/thumbnails/10.jpg)
Valid SPST Tree
R
A
X
M
Y
Level 0
Level 1
Level 2
Level 3
Level 4
![Page 11: Fault Management in Mobile Ad-Hoc Networks by Tridib Mukherjee](https://reader035.vdocuments.site/reader035/viewer/2022070418/5697bfde1a28abf838cb2581/html5/thumbnails/11.jpg)
M moves out
R
A
C
X
D
M
Y
Level 0
Level 1
Level 2
Level 3
Level 4
can_stabilize(Y) is falsecan_stabilize(X) is falsecan_stabilize(C) is falsecan_stabilize(D) is false
![Page 12: Fault Management in Mobile Ad-Hoc Networks by Tridib Mukherjee](https://reader035.vdocuments.site/reader035/viewer/2022070418/5697bfde1a28abf838cb2581/html5/thumbnails/12.jpg)
This is NFC fault
R
A
X
Y
Level 2
Level 3
![Page 13: Fault Management in Mobile Ad-Hoc Networks by Tridib Mukherjee](https://reader035.vdocuments.site/reader035/viewer/2022070418/5697bfde1a28abf838cb2581/html5/thumbnails/13.jpg)
Neighborhood of Y is different
R
A
C
X
D
M
Y
Level 0
Level 1
Level 2
Level 3
Level 4
can_stabilize(Y) is truecan_stabilize(A) is falsecan_stabilize(C) is falsecan_stabilize(D) is false
![Page 14: Fault Management in Mobile Ad-Hoc Networks by Tridib Mukherjee](https://reader035.vdocuments.site/reader035/viewer/2022070418/5697bfde1a28abf838cb2581/html5/thumbnails/14.jpg)
FC faults
The scenario of the previous slideFaults occurred due to corruption are FC
faultsBoth NFC and FC faults can occur in
multiple nodes simultaneouslyFor NFC faults, self stabilization is
executed internally
![Page 15: Fault Management in Mobile Ad-Hoc Networks by Tridib Mukherjee](https://reader035.vdocuments.site/reader035/viewer/2022070418/5697bfde1a28abf838cb2581/html5/thumbnails/15.jpg)
Two FC faults within 2 hops
R M
X
AY B
• Level of A gets corrupted to 6 • M moves out and X becomes the parent of Y • Both the FC faults become Non-containable • Distance of 2 hops is named as Containability Limit (CL)
0 1 2 3 4 5
![Page 16: Fault Management in Mobile Ad-Hoc Networks by Tridib Mukherjee](https://reader035.vdocuments.site/reader035/viewer/2022070418/5697bfde1a28abf838cb2581/html5/thumbnails/16.jpg)
Reason
Gp(Y) and Gp(A) are true
Can_stabilize(Y) and Can_stabilize(A) are false
So Fault Containing Algorithm executes self-stabilization internally
FC faults becomes NFC if they occur within CL
![Page 17: Fault Management in Mobile Ad-Hoc Networks by Tridib Mukherjee](https://reader035.vdocuments.site/reader035/viewer/2022070418/5697bfde1a28abf838cb2581/html5/thumbnails/17.jpg)
Improved_Can_Stabilize
Check if local action can nullify Gp in all the two hop neighbors instead of one hop neighbors as in the original algorithm
Otherwise check if local actions in all the one hop neighbors can eradicate fault in all the two hop neighbors
![Page 18: Fault Management in Mobile Ad-Hoc Networks by Tridib Mukherjee](https://reader035.vdocuments.site/reader035/viewer/2022070418/5697bfde1a28abf838cb2581/html5/thumbnails/18.jpg)
Improved Fault-containment
![Page 19: Fault Management in Mobile Ad-Hoc Networks by Tridib Mukherjee](https://reader035.vdocuments.site/reader035/viewer/2022070418/5697bfde1a28abf838cb2581/html5/thumbnails/19.jpg)
Reasoning
Gp(Y) and Gp(A) are true
Can_stabilize(Y) and Can_stabilize(A) are also true
Fault Containing Algorithm executes self-stabilization internally only if faults are NFC
Containability Limit is 0
![Page 20: Fault Management in Mobile Ad-Hoc Networks by Tridib Mukherjee](https://reader035.vdocuments.site/reader035/viewer/2022070418/5697bfde1a28abf838cb2581/html5/thumbnails/20.jpg)
Simulation
Simulation is done in NS2Comparison between Self-stabilization,
Fault-containment and Improved Fault-containment
Simulation is done for NFC and FC faults as well as multiple FC faults occurring within CL
Performance is measured in terms of Beacon Intervals
![Page 21: Fault Management in Mobile Ad-Hoc Networks by Tridib Mukherjee](https://reader035.vdocuments.site/reader035/viewer/2022070418/5697bfde1a28abf838cb2581/html5/thumbnails/21.jpg)
NFC Fault Simulation Result
![Page 22: Fault Management in Mobile Ad-Hoc Networks by Tridib Mukherjee](https://reader035.vdocuments.site/reader035/viewer/2022070418/5697bfde1a28abf838cb2581/html5/thumbnails/22.jpg)
FC faults with distance greater than CL
![Page 23: Fault Management in Mobile Ad-Hoc Networks by Tridib Mukherjee](https://reader035.vdocuments.site/reader035/viewer/2022070418/5697bfde1a28abf838cb2581/html5/thumbnails/23.jpg)
FC faults with distance less than CL
![Page 24: Fault Management in Mobile Ad-Hoc Networks by Tridib Mukherjee](https://reader035.vdocuments.site/reader035/viewer/2022070418/5697bfde1a28abf838cb2581/html5/thumbnails/24.jpg)
Advantages & Disadvantages
If a fault can be contained, it is contained regardless of its occurrence in the network
Costs more communication overhead if a fault is not containable
![Page 25: Fault Management in Mobile Ad-Hoc Networks by Tridib Mukherjee](https://reader035.vdocuments.site/reader035/viewer/2022070418/5697bfde1a28abf838cb2581/html5/thumbnails/25.jpg)
References
Sukumar Ghosh, Arobinda Gupta, Sriram V. Pemmaraju. ”Fault-containing network protocols”. Proceedings of the 1997 ACM symposium on Applied computing, p.431-37, April 1997, San Jose, California, United States.
Sukumar Ghosh, Arobinda Gupta, T. Herman, Sriram V. Pemmaraju. Faultcontaining Self-Stabilizing Algorithms”. 15th Annual ACM Symposium on Principles of Distributed Computing, 1996, pp. 45-54.
![Page 26: Fault Management in Mobile Ad-Hoc Networks by Tridib Mukherjee](https://reader035.vdocuments.site/reader035/viewer/2022070418/5697bfde1a28abf838cb2581/html5/thumbnails/26.jpg)
References (Contd…)
Sandeep K. S. Gupta, Pradip K. Srimani. ”Self-stabilizing multicast protocols for ad hoc networks”. Journal of Parallel and Distributed Computing 63(1): 87-96 (2003)
![Page 27: Fault Management in Mobile Ad-Hoc Networks by Tridib Mukherjee](https://reader035.vdocuments.site/reader035/viewer/2022070418/5697bfde1a28abf838cb2581/html5/thumbnails/27.jpg)
Questions?