Designing a Better Watchdog Mechanism to Solve Collision
Related Problem in MANET

We Are

SHAKIL, AZIZUL HAKIM
13-23005-1

TALUKDER, MD. RAIHAN
13-23067-1

ZAMAN, KHALID SYFULLAH
13-23099-1

RAIHAN, MD. ASIF
13-23979-2

Outline

Background

Literature Review

MANET & Watchdog

Previous Flow Chart

Mathematical Derivation

Discussion

Result

Conclusion

Future Work

Proposed Flow Chart

Background

This is an improved work on algorithm of Enhanced Adaptive ACKnowledgement(EAACK) proposed by Researchers of Acadia University named Nan Kang and Elhadi M. Shakshuki and researcher of King Fahd University named Tarek R. Sheltami

They Proposed a new IDS that solves four significant problems of Watchdog mechanism which are ambiguous collision, receiver collision, limited transmission power and false misbehavior report.

Literature Review

This Thesis work is persuaded from the earlier work of evaluation on Watchdog Mechanism

Earlier works used methods for getting a good result in packet delivery    ratio and throughput

Following neighborhood-based method for detecting black hole attack  using routing recovery protocol established the path to the true    destination results a less severe impact on black hole attack.

Neither of previous work gives us a better result that can remove ambiguous collision and collision in the receiver.

Manet

Mobile Ad Hoc Network(MANET) is a
decentralized wireless network that communicates by forming mobile radio network.

Introduction to Watchdog

Watchdog Mechanism is a monitoring technique that helps to detect the misbehaving node.

It basically used to observe the forwarding pattern of next hop.

It cannot identify the status of the receiver.

Watchdog is activated if a node wants to
monitor function in the neighboring node.

Watchdog(Cont...)

For Ambiguous Collision, the collisions prevent node A from overhearing the transmission of Packet 1 from node B to node D due to another packet(i.e. Packet 2) sent from node S.

S

A

B

D

Packet 1

Packet 1

Packet 2

Overhearing

Watchdog(Cont...)

For Receiver Collision, node A assures that node B has forwarded Packet 1 to node D, but fails to detect that node D never received Packet 2 due to a collision with Packet 2.

S

A

B

D

Overhearing

Request for packet 2

packet 2 send

Previous Flowchart

Proposed Flowchart

Start

Find Shortest Route

Set Route Buffer

Calculate Threshold
& Set Threshold Buffer

Start Packet Sending

Node Activity

Misbehaving Report

Add Misbehave Node to

Reply From Destination

the Buffer

Find new Route from last

success Node

Update Route Buffer

Update Threshold Buffer

No

No

YES

YES

Node Activity

Pck. Received Time> N-N Th. Time

Misbehave Report Occured

No Misbehave Report

Here, N = Node

Mathematical Derivation

Collision Related:

For Receiver Collision,

S

A

B

D

request for packet 2

packet 2 send

For Ambiguous Collision,

S

A

B

D

P1

request P2

Node 'S' takes time to send 'P2'; in the meantime node 'A' request for 'P2' again and then collision happened..

S

A

B

D

request P2

P2

By using One-time Signature Scheme on AODV(Ad-hoc On Demand Distance Vector) protocol,

S

A

B

D

t

t

t

2

1

0

S

A

B

D

t

t

t

3

4

5

S

A

B

D

t

t

t

8

7

6

1st packet send

requesting for 2nd packet

2nd packet send

Time Related:

Packet received time form node-to-node = t

[Note that, received time counter starts from 0(zero)]

If, number of node is n and number of packet is j

Then, packet received time to destination node = tnj

Time difference between packets' received time is d

Number of Packets,  P = j - 1

[1st Packet starts from t0 ]

So, Total Time Consumption = TdP+(n-2)

Received nth no. Packet at tnj = TdP+(n-2)

But applying on AODV protocol using one-time signature scheme, difference between packets' received time gets TWICE or more than TWICE.

From The Next Packet = T{2dP+(n-2)}+{2*(n-4)}

Received 1st Packet at tnj = T2dP+(n-2)

where n >= 4

1

2

3

4

5

6

number of Packet(P)

t8

t16

t4

t12

t2

t5

t8

t11

t14

t17

Here, number of nodes, n = 4
and difference, d = 3 (Const.)

Applying
TdP+(n-2)

Discussion

Where, Ambiguous Collision
(n - 1)

Receiver Collision
(n - 2)

t20

t24

On AODV protocol using one-time signature scheme,
      difference is 2d (where, d=3 [Const.]) which is 6.

Applying
T{2dP+(n-2)}+{2*(n-4)}

Both Collision = 0
(almost)

1

2

3

4

5

6

number of Packet(P)

t12

t24

t6

t18

t2

t8

t14

t20

t26

t32

t30

t36

Result

More efficient to reduce the collisions (ambiguous and receiving collision)

Time-consuming

Data drop reduce (collision related)

Conclusion

Reduce ambiguous and receiving collision

Data transfer accuracy increases

Network reliability increases

Future Work

Implement to any Network Simulator

Reduce the time more

Lead to optimal solution

THANK YOU!