Prophet Address Allocation for Large Scale MANETs

Matt W. Mutka Dept. of Computer Science & Engineering

Michigan State University East Lansing, USA

IEEE INFOCOM 2003

Outline

IntroductionRelated WorkProphet AllocationPerformance AnalysisSimulationConclusion

Introduction

Hard-Wired NetworkAutomatic address allocation

DHCP

MANETAutomatic address allocation

Instability of mobile nodesLow bandwidthOpenness of MANETLack of central administration

Motivation

Avoid address conflict A feasible auto-configuration algorithm should handle the following three scenarios:

A mobile node simply joins a MANET and then leaves it forever.A MANET partitions and then the partitions merge later.Two separately configured MANETs merge

Introduction - Scenario A

Introduction - Scenario B

Introduction - Scenario C

Related Work - Allocation Method

Conflict-detection allocationTrial and error

Conflict-free allocationDivided to disjoint part

Best-effort allocationDDHCP( Maintain a global allocation state)

Prophet allocationLocal communicationEven distribution

Prophet allocation - Assumption

R is a range of avilable IP address range.f(n) is integer sequence consisting of numbers in RThe initial state of f(n) is called the seed.

The interval between two occurrences of the same number in a sequence is extremely long;The probability of more than one occurrence of the same number in a limited number of different sequences initiated by different seeds during some interval is extremely low.

Prophet allocation - Protocol Example

A

1.Choose random IP and random state value (address, state of f(n))

B

3.A Use f(n) to generate IP and state value

2.When B Join and ask A for Free IP

4.Assign the generated IP and state address to B

5.A change its state value accordingly

Prophet allocation – Protocol DescribtionRandom IP and random state value (address, state of f(n))

B approaches A and asks A for a free IP

f(n)=(3x3x11)mod 7=1 so A change the state of f(n) to 1 and assign to B.

C join and D join , approaches A and B , asks for a free IP

f(n)=(3x1x11)mod 7=5 and f(n)=(1x1x11)mod 7=4

If there are more node join -><- because the small range of R

Prophet allocation – Partition and merge

Scenario BCause the sequences are different

Scenario CWe designate the first node in the MANET to generate the random network ID(NID)

Prophet allocation – Design of f(n)

Generate different k-tuples.If k=4

A is (address,(e1,e2,e3,e4))Address= (a+2e13e25e27e3)

1.The under-line element increase by 1

2.The new node get the ip and underline shifts right 1

Protocol

Un-initialized

Local conflict resolution

Configured

Waiting

1.Switch to ad-hoc mode and broadcast state request (one hop broadcast)

2.Retries <=k Repeat Broadcast

3.if Received Response IP address Intial state value NIDelse set to defult

5. Send HELLO Msg when received state request reply and update state

6.If received different NID switch to Local conflict resolution

7.Finish

8.Ends the session

Performance evaluation

Distributed operationCorrectnessComplexityCommunication overheadEvennessLatencyScalability

Performance comparisonCharacteristics summary

Qualitative evaluation

Simulation - Assumption

DSR routing protocolMobile nodes join the MANET every 30 secondsSimulation for 3 nodesThe area size was chosen to make all the nodes connected in the topology.

Simulation - Communication Overhead

Simulation - Communication Overhead

Simulation - Latency

Simulation - Latency

Conclusion

Prophet allocation is for large scale MANETs,

Low complexity,Large communication, Even distribution Low latency.

Thank You