Prophet Address Allocation for Large Scale MANETs

1. Prophet Address Allocation for Large Scale MANETs Matt W. Mutka Dept. of Computer Science & Engineering Michigan State University East Lansing, USA IEEE INFOCOM 2003

2. Outline • Introduction • Related Work • Prophet Allocation • Performance Analysis • Simulation • Conclusion

3. 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

4. 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

5. Introduction - Scenario A

6. Introduction - Scenario B

7. Introduction - Scenario C

8. 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

9. 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.

10. 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

11. 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

12. 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)

13. 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

14. Protocol 2.Retries <=k Repeat Broadcast Waiting Un-initialized 1.Switch to ad-hoc mode and broadcast state request (one hop broadcast) 3. if Received Response IP address Intial state value NID else set to defult 8.Ends the session Configured Local conflict resolution 6.If received different NID switch to Local conflict resolution 7.Finish 5. Send HELLO Msg when received state request reply and update state

15. Performance evaluation • Distributed operation • Correctness • Complexity • Communication overhead • Evenness • Latency • Scalability

16. Performance comparison Characteristics summary Qualitative evaluation

17. 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.

18. Simulation - Communication Overhead

19. Simulation - Communication Overhead

20. Simulation - Latency

21. Simulation - Latency

22. Conclusion • Prophet allocation is for large scale MANETs, • Low complexity, • Large communication, • Even distribution • Low latency.

23. Thank You