1. MPR-Aware Performance Improvement for Inter-Domain Routing in MANETs
You Lu, Yenan Lin, Biao Zhou, Mario Gerla
UCLA

2. Introduction & Previous Work New features
Outline
Introduction & Previous Work
New features
Dynamic TDMA
MPR-aware Slot Allocation for OLSR
MPR-aware Gateway selection
Simulation Results
Throughput increased efficiency
Reduced Control Overhead
Conclusions

3. Inter-Domain Routing for MANETs
Previous Work
Inter-Domain Routing for MANETs
Group Mobility
One Cluster head per Group
Cluster heads periodically advertise member list
Advertisements propagate via dissemination A
LISTA B
LISTB

4. TDMA domain is the bottleneck
Previous Work
TDMA domain is the bottleneck
Inefficient slot usage
Three categories of TDMA
Static TDMA
Cluster TDMA
Dynamic TDMA

5. Our Approach: DTDMA
Slot Allocation for Node 1 contention area

6. DTDMA performance much better than STDMA
DTDMA with OLSR +MPR
DTDMA performance much better than STDMA
Same slot reused in different contention areas
However:
Can we further improve performance?
Yes, if OLSR is used in the TDMA domain
Key idea: assign multiple slots to “popular” nodes, such as Multipoint Relay Nodes (MPR)

7. OLSR: Multi Point Relays

8. New Feature: multiple slots for MPRs
MPR-aware slot allocation:
MPR nodes get more slots than regular nodes
Motivation: MPRs form the “backbone”
They are the nodes that do most store and forwarding
MPRS = MPR Selector, the node that selects that MPR
The more Selectors, the more popular the MPR

9. DTDMA : MPR Selectors Selectors for MPR in node 3 MPRS MPRS MPR MPRS

10. MPR- aware Gateway selection
More on MPR
MPR- aware Gateway selection
- Can further improve performance by selecting as Gateway a popular MPR Node
- Assign candidate Gateways the WEIGHT:

11. Performance Evaluation
Simulator: Qualnet 5.0.2
Data traffic: CBR, pkt size 512 byte
Geographic area: 2000m × 2000m
Mobility model: RPGM
In each domain the Reference Point moves randomly. All nodes in the domain move around the RP
intra-group speed: 0-5m/s
pause time is 10 seconds
MAC protocols: CSMA & TDMA
Routing protocols: AODV & OLSR
Metrics:
Average Receiver Throughput & Normalized Control Overhead

12. Average Delivered Throughput
The larger the density, the larger the frame for the
Contention set => the lower the throughput

13. Normalized Control Overhead

14. Conclusion Dynamic TDMA +OLSR: We get: MPR-aware Slot Allocation
MPR-aware Gateway Selection
We get:
Throughput improvement
Reduced Control Overhead

15. Thanks
Q & A