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
Introduction
Related Work
Prophet Allocation
Performance Analysis
Simulation
Conclusion
Introduction
Hard-Wired Network
Automatic address allocation
DHCP
MANET
Automatic address allocation
Instability of mobile nodes
Low bandwidth
Openness of MANET
Lack 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 allocation
Trial and error
Conflict-free allocation
Divided to disjoint part
Best-effort allocation
DDHCP( Maintain a global allocation state)
Prophet allocation
Local communication
Even distribution
Prophet allocation -
Assumption
R is a range of avilable IP address range.
f(n) is integer sequence consisting of
numbers in R
The 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
B
1.Choose random IP and random state value (address, state of f(n))
2.When B Join and ask A for Free IP
3.A Use f(n) to generate IP and state value
4.Assign the generated IP and state address to B
5.A change its state value accordingly
Prophet allocation –
Protocol Describtion
Random 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 B
Cause the sequences are different
Scenario C
We designate the first node in the MANET to
generate the random network ID(NID)
Prophet allocation –
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
Design of f(n)
Protocol
Un-initialized
2.Retries <=k
Repeat Broadcast
1.Switch to ad-hoc mode and
broadcast state request
(one hop broadcast)
Waiting
3.
8.Ends the session if Received Response
IP address
Intial state value
NID
else set to defult
Configured
6.If received different NID
switch to Local conflict
resolution
7.Finish
5. Send HELLO Msg
when received state
request reply and update
state
Local conflict
resolution
Performance evaluation
Distributed operation
Correctness
Complexity
Communication overhead
Evenness
Latency
Scalability
Performance comparison
Characteristics summary
Qualitative evaluation
Simulation -
Assumption
DSR routing protocol
Mobile nodes join the MANET every 30
seconds
Simulation for 3 nodes
The 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