The Selective Intermediate Nodes Scheme for Ad Hoc On-Demand Routing Protocols

Yunjung Yi, Mario gerla and Taek Jin Kwon

ICC 2002

Outline Introduction Selective Intermediate Nodes (SIN)

Characteristics Local load level measurement Reactive protocols with SIN algorithm

Simulation and experiments Simulation Model Simulation Results

Conclusion

Introduction

The classification of ad hoc routing protocols Proactive routing protocols

OSPF OLSR

Reactive routing protocols AODV DSR

Introduction

Load aware routing Load-balanced distribution of data

traffic over the network. Efficient flooding (EF)

Permits only a subset of the network to participate in flooding.

Several potential drawbacks

Selective Intermediate Nodes (SIN) Characteristics

Selective Intermediate Nodes (SIN) scheme

Retrains a node base on the stress level of the local network and the cluster status.

Light Load Moderate Saturated

Selective Intermediate Nodes (SIN) Characteristics

Selective Intermediate Nodes (SIN) Characteristics

Accurate measurement of the local load Assume each node uses 802.11 DCF MAC protocol.

Classification of channel status of an ad hoc network

IDLE 、 TRANSMITTING 、 RECEIVING and COLLISION

Accumulates the duration in idle_time 、 trans_time 、 recv_time and coll_time Ex.Idle_time = α * idle_time + (1 – α) * prev_idle_time

Selective Intermediate Nodes (SIN) Characteristics Channel utilization

Transmission probability

INTERVL

timeidleUi

_1

INTERVL

timetransTXi

_

Selective Intermediate Nodes (SIN) Characteristics

Collision duration

　INTERVAL

timecollratecoll

__

TIMESLOTINTERVALratecollTc __

Selective Intermediate Nodes (SIN) Characteristics

Two algorithms to decide local load level (Li) Simple Algorithm (SMIPLE) Fair-share Algorithm (FS)

Selective Intermediate Nodes (SIN) Characteristics

SMIPLE Li ← IDLE if Ui < CHANNEL_IDLE_THRESHOLD

Li ← SATURATED and ClusterStatus← ORDINARY NODEif (Ui > Pmax + p) or (Qi > QUEUE_THRESHOLD)

Otherwise, Li ← MODERATE

Selective Intermediate Nodes (SIN) Characteristics Fair-share Algorithm （ FS ）

Li ← SATURATED and ClusterStatus ← ORDINARY NODE if (Ui > Pmax + p) or (Qi > QUEUE_THRESHOLD) or

(ANi > 2 and TXi > TRANSopt)

Optimal transmission probability

2

1

TCNTRANSopt

Selective Intermediate Nodes (SIN) Characteristics

D

S

Time out

RREQ

RREP

AODV Example

Selective Intermediate Nodes (SIN) Characteristics Reactive Protocols with SIN

algorithm AODV (Ad hoc On-demand Distance

Vector Routing) When a new RREQ comes in with TTL

greater than “0” When the local load level (Li) is

IDLE : every node forwards the RREQ MODERATE : only cluster heads and

gateways forward RREQ SATURATED : every node stops forwarding

DSR Example: route request

N1

N2

N3

N5 N8

N4 N7

N6

N1

N1

Source

N1-N3

N1-N2

N1-N3-N4

N1-N3-N4

N1-N3-N4N1-N3-N4-N7

N1-N3-N4-N6

N1-N3-N5Destination

Selective Intermediate Nodes (SIN) Characteristics

Selective Intermediate Nodes (SIN) Characteristics

N1

N2

N3

N5 N8

N4 N7

N6

Source

Destination

N1-N2-N5-N8

N1-N2-N5-N8

N1-N2-N5-N8

DSR Example: route reply

Selective Intermediate Nodes (SIN) Characteristics DSR (Dynamic Source Routing)

When a new RREQ comes in with TTL greater than “0”

The same mechanism in the modification of AODV

When Li -> IDLE or Li -> MODRATE and node is a (cluster head or gateway)

When a node learns a shorter path than current path to the destination, sends a “gratuitous” reply only

An intermediate node initiate the route reply if it already knows the route to the destination

Simulation and experiments Simulation Model

Item Content

Library Global Mobile Simulation (GloMoSim)

Protocol UDP, AODV/DSR, IEEE 802.11 DCF, two-ray radio propagation

Mobility Random-way, Default 20m/s

Bandwidth

2 Mbits/Second

Transmission range

250 meters

Simulation and experiments Simulation Model

Item Content

INTERVAL 1s

CHANNEL_IDLE_THRESHOLD

0.2

Pmax 0.8

QUEUE_THRESHOLD 0.8*MAX_QUEUE

Each result runs time 600 seconds

Simulation and experiments Simulation Results

Testing with Increasing Offered Load

Simulation and experiments Simulation Results

Testing with Increasing Offered Load

Simulation and experiments Simulation Results

Testing with Increasing Offered Load

Simulation and experiments Simulation Results

Testing with Increasing Offered Load

Simulation and experiments Simulation Results

Testing with Increasing Offered Load

Simulation and experiments Simulation Results

Testing with Increasing Offered Load

Simulation and experiments Simulation Results

Testing with Increasing Offered Load

Simulation and experiments Simulation Results

Testing Scalability and Adaptability with Increasing the Number of Node

Conclusion

Provide two algorithms that decide the saturation point.

Proposed Selective Intermediate Nodes scheme that controls the offered load.