1. AODV-OLSR Scalable Ad hoc Routing
J. Costa-Requena, T. Vadar, R. Kantolaand N. Beijar,
Helsinki University of Technology
Wireless Pervasive Computing
2006 1st International Symposium Jan 2006
Wang Xiaofei
( )
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2. Contents 1.Introduction 2.AODV-OLSR Scalable Ad hoc Routing Protocol
3.Virtual Backbone & Hierarchical Group
4.Simulation
5.Conclusion
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3. 1.Introduction (1/2) Proactive Protocols Reactive Protocols
Build routes & exchange info among nodes periodically
OLSR :Optimized Link State Routing
DSDV :Dynamic Destination-Sequenced Distance-Vector routing …
Reactive Protocols
Build routes only when node requires
AODV :Ad-hoc On-demand Distance-Vector routing
DSR :Dynamic Source routing
TORA :Temporally Ordered Routing Algorithm
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4. 1.Introduction (2/2) Hybrid approaches LAR :Location Aided Routing
ZRP :Zone Routing Protocol
IARP :Intra-Zone Routing Protocol - proactive
LERP :Inter-Zone Routing Protocol – reactive …
SARP : Scalable Ad hoc Routing Protocol
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5. 2.AODV-OLSR Scalable Routing (1/2)
AODV-OLSR Scalable Ad hoc Routing Protocol
Two types of nodes:
Smart Node
Have enough resources and willingness to maintain route and service information.
OLSR with other smart nodes for exchanging route updates.
AODV with dummy nodes.
Dummy Node
Limited resources
AODV only
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6. 2.AODV-OLSR Scalable Routing (2/2)
Scalable Ad hoc Routing
“Zone” : area of dummy nodes around a smart node
Looks like an opposite approach to ZRP
Intra-zone : reactive (AODV)
AODV suits much for small networks
Inter-zone : proactive (OLSR)
OLSR suits much for relatively stable networks
Smart nodes form virtual link paths
Use OLSR in these paths.
Virtual fully distributed backbone
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7. 3.Virtual Backbone & Hierarchical Group (1/4)
Virtual fully distributed backbone
Smart nodes create virtual backbone and exchange link state information between them for sharing network topology and increase the overall scalability
virtual layer of backbone
Real network
Dummy nodes only benefit from smart nodes and use AODV routing with others
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8. 3.Virtual Backbone & Hierarchical Group (2/4)
Hierarchical smart nodes group
Link State Updates
All the other smart nodes are included in different group based on the distance (hop number)
Each smart node has OLSR route tables and also a hierarchical group table
“Group3” includes all other smart nodes located 3 hops away
For example: This is SmartNode1’s group table
G1: S2
G2: -
G3: S3, S4, S5
G4: 6
G5: S8, S9
G6: S7, S10, S11
SmartNode1 can take 6 hops to reach S7, S10, S11 …
How to form? How to use?
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9. Here is an example network, and S1 is requiring attachment
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10. 3.Virtual Backbone & Hierarchical Group (4/4)
G1: S2
G2: -
G3: S3, S4, S5
G4: 6
G5: S8, S9
G6: S7, S10, S11
Different routing update frequency
Far : lower freq.
Near: higher freq.
Link State Update 2K*T
Hop distance
T : minimum LSU transmission period
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11. 4.Simulation (1/4)
SARP protocol is implemented in NS-2 integrating existing implementations of AODV and OLSR
Parameters :
Nodes :50
Area :1500m x 300m
30 constant bit rate IP connections of 8packets/second
64 bytes/packet
Mobility: 0 ~ 900s (pause time between movements)
Average after 3 rounds of simulations
“SARP-10” : 10 smart, 40 dummy nodes
Comparison among signaling overhead, delay, data throughput and node mobility
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12. 4.Simulation (2/4)
Routing overhead VS node mobility
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13. Here, SARP-10&15 is better than AODV !
4.Simulation (3/4)
Packet delay VS nodes mobility
Here, SARP-10&15 is better than AODV !
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14. 4.Simulation (4/4) Data throughput(%) VS Nodes mobility
Here, SARP-10 is better than AODV !
Tradeoff : the density of smart nodes , node mobility
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15. 5.Conclusion (1/2) Conclusion:
Introduced and compared some Ad hoc routing methods
Presented a new hybrid AODV-OLSR scalable routing.
Simulation and comparison
SARP has a good performance and even a little better than AODV in some situations.
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16. 5.Conclusion (2/2) Questions & future works:
Is it really feasible and effective to implement two routing algorithms in one node…?
There should be a tradeoff on the ratio of smart nodes number to dummy nodes number, then it could get much better effect for various scenario ?
Scalability: in different situations, the density should be able to be modified automatically to suit for the whole network in order to get better performance.
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17. Thank you !
Q&A or Comment
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