ANTHOCNETHYBRID ROUTING ALGORITHM

FOR MANET

Guided ByShalini LAsst. Prof. CSE Dept.

Presented ByDhanith Krishna BS7 CSE

1

Presentation Structure

INTRODUCTION

MANETS

CHALLENGES IN MANETS

ROUTING ALGORITHMS

ANTHOCNET

REACTIVE ROUTE SETUP

PROACTIVE ROUTE MAINTENANCE

STOCHASTIC DATA FORWARDING

LINK FAILURES

ADVANTAGES

2

History

First network – ARPANET

3

History

First Wireless network – ALOHANET

4

Traditional Networks

Fixed infrastructure

Dedicated Communication Devices

AP

BA

5

MANET

MOBILE AD HOC NETWORK

Continuously self-configuring

Infrastructure-less network

Connected without wires.

A B C D

6

MANET

Each device is router.

7

Properties

Host movement frequent

Topology change frequent

Decentralized and scalable

8

Examples

VANET

9

Examples

TACTICAL NETWORKS

10

Routing ???

selecting best paths in a network.

11

Challenges

Dynamic topology

Unidirectional Links

Power Constraints

12

Where to find

an answer ?

13

Ants Ants Everywhere

14

Ants

Can explore vast areas without global view of the ground.

Can find the food and bring it back to the nest.

Will converge to the shortest path.

15

Ants

Communication using pheromones.

Explored area is marked with pheromone

Other ants find explored path by sensing pheromones

16

Double Bridge Experiment

17

Back to

Reality

18

Routing Protocols

Proactive Routing ProtocolsTable DrivenEach Node Knows Network Topology

Reactive Routing ProtocolsOn Demand Routing

19

AntHocNet

Hybrid Routing Protocol

Has both Reactive and Proactive components

Developed by Di Caro et al

20

Overview

Reactive path setup

Stochastic data routing

Proactive path maintenance and exploration

Handling of link failures

21

Data Structures

Pheromone Table

Neighbour Table

Each node has two tables

22

Pheromone Table

Regular Pheromone rijd

Virtual Pheromone wijd

Average Hop Count hijd

Helps in making routing decisions

23

Neighbour Table

Helps in identifying neighbours of a node

24

Reactive path setup

Occurs when path from source to destination is unknown.

S

F

A

H

G

B C

I

J

DSource Destination

25

Reactive path setup

A reactive forward ant is broadcasted from source to destination.

S

F

A

H

G

B C

I

J

DSource Destination

[s]

[s]

26

Reactive path setup

Intermediate node unicasts or broadcasts ant packet to neighbours depending on whether it knows the route to destination or not.

S

F

A

H

G

B C

I

J

DSource Destination

[S,A]

[S,F]

27

Reactive path setup

A node that receives two copies of an ant forwards only one ant.

S

F

A

H

G

B C

I

J

DSource Destination

[S,A,B]

[S,F,H]

[S,F,G]

28

Reactive path setup

This method of working is called flooding.

S

F

A

H

G

B C

I

J

DSource Destination

[S,A,B,C]

[S,F,H,I]

[S,A,B,G]

29

Reactive path setup

S

F

A

H

G

B C

I

J

DSource Destination

[S,A,B,C]

[S,F,H,I]

30

Reactive path setup

First ant reaching destination finds the best path

S

F

A

H

G

B C

I

J

DSource Destination

[S,A,B,C,D]

[S,F,H,I,J]

31

Reactive path setup

Other ants are rejected.

S

F

A

H

G

B C

I

J

DSource Destination

[S,F,H,I,J,D]

32

Reactive Backward Ant

First ant to reach destination is made a backward ant.

It traverses the best path in reverse.

On the way the pheromone table is updated at all visiting nodes.

33

Reactive Backward Ant

Hop count is updated as

Regular pheromone is updated as

34

Data Routing

Once path is setup data is stochastically routed.

35

Data Routing

I

D

A

B

C

Source Destination

36

Proactive Path Maintenance

Pheromone Dissolution

End to End path sampling

37

Pheromone Dissolution

Every node broadcasts a hello message to all neighbours.

The pheromone table is piggybacked to the hello packet.

38

End to End Path Sampling

While the session is active proactive ant agents explore to find additional paths.

Proactive ants like forward ants update pheromone table when it becomes a backward ant.

39

Link Failures

Hello messages help to find link failures.

The link failure is notified to all nodes by flooding.

Repair ants try to find alternate path to destination if failure is in the midst of a transmission.

40

Advantages

Automatic load Balancing.

Higher Delivery ratio.

Robust , Adaptive and scalable.

41

References

[1] The internet engineering task force mobile ad-hoc networkingpage(MANET). Available from: http://www.ietf.org/html.charters/manet-charter.html.

[2] Microsoft Mesh Networks. Available from: http://research.microsoft.com/mesh/.

[3] ANTHOCNET, Available from http://www.idsia.ch/~frederick /anthocnet/anthocnet.html

[4] B. Baran and R. Sosa. A new approach for AntNet routing. InProceedings of the 9th International Conference on ComputerCommunications Networks, Las Vegas, USA, 2000.

Thank You

Queries