1. Dilshad Haleem CST593 summer 2007 Routing In Wireless Mesh Networks CST593 Final Project by Dilshad Haleem Division of Computing Studies, ASU Polytechnic

2. Dilshad Haleem CST593 summer 2007 CST593 Committee Chair : Dr. Bruce R. Millard Member : Dr. Alan Skousen Member: Dr. Timothy E. Lindquist

3. Dilshad Haleem CST593 summer 2007 Introduction Wireless Mesh Networks are radio based self configuring networks, with minimal infrastructure requirements Nodes operate as host and also as a router Reliable, resilient and robust Different than Mobile Ad Hoc Networks

4. Dilshad Haleem CST593 summer 2007 Architecture Reference: http://www.primidi.com/2005/01/04.html

5. Dilshad Haleem CST593 summer 2007 Difference between WMNs and MANETs Mesh Routers are relatively static No power constraints Traffic concentration may be higher in certain paths (hot spots) Number of users

6. Dilshad Haleem CST593 summer 2007 Ad Hoc On Demand (AODV) A protocol developed for MANETs Reactive in operation Route discovery and maintenance using control packets (RREQ, RREP, RERR and HELLO) Uses minimum hop count as the performance metric

7. Dilshad Haleem CST593 summer 2007 Problem Statement Creating Wireless Mesh Network and Ad Hoc Network scenarios in OPNET Modeler Simulating AODV in Wireless Mesh and Wireless Ad Hoc Networks Performance comparison Implementation of Expected Transmission Count (ETX) as a Process Model in OPNET

8. Dilshad Haleem CST593 summer 2007 Wireless Ad Hoc Network VS WMN

9. Dilshad Haleem CST593 summer 2007 AODV and WLAN Parameters

10. Dilshad Haleem CST593 summer 2007 Simulation Results End to End Delay High Delay is observed in WMN Probable reason, nodes closer to the GW, are relaying theirs and other nodes’ traffic MAC layer Fairness

11. Dilshad Haleem CST593 summer 2007 Simulation Results Routing Traffic Received More RREQ and RREP in Ad Hoc Network Routes do not change frequently in WMN Mostly in case of node failure or new node joining

12. Dilshad Haleem CST593 summer 2007 Simulation Results Routing Traffic Sent

13. Dilshad Haleem CST593 summer 2007 Simulation Results Throughput Less throughput is observed in WMN Throughput decreases as the number of hops increases

14. Dilshad Haleem CST593 summer 2007 Simulation Results Throughput of node_7 & node_9 Node_7 enjoys a higher throughput, than node_9 Node_9 is 3-hops away from the Gateway

15. Dilshad Haleem CST593 summer 2007 Expected Number of Transmission (ETX) Routing Protocol must be aware of the consequence of path selection Routing protocol must be aware of the link condition Link layer performance metric, ETX is the loss rate of broadcast packets between pair of nodes

16. Dilshad Haleem CST593 summer 2007 Implementation of ETX Nodes broadcast probe packets(134 bytes) once per second Nodes keep track of the number of probes received in 10 seconds Reverse delivery ratio = pkt rcvd / pkt sent Forward delivery ratio is obtained from the neighbors’ probe

17. Dilshad Haleem CST593 summer 2007 Implementation of ETX in OPNET Node Model Pkt_src processor generates probe packets Calc_ETX module calculates ETX Rcv and xmt modules rcv and tx the packets

18. Dilshad Haleem CST593 summer 2007 Implementation of ETX in OPNET Calc_ETX Process Model (FSM) INIT state performs initialization of State variables Time_out state reset the packet count every 10 seconds and calculates ETX Idle state waits until a packet needs to be sent or received

19. Dilshad Haleem CST593 summer 2007 Implementation of ETX in OPNET Calc_ETX Network Model 2 nodes Network Model Data rate is set to 11Mbps

20. Dilshad Haleem CST593 summer 2007 Simulation Results of ETX Model Reverse Delivery Ratio = pkt rcvd / pkt sent = 10/10 =1 Forward Delivery ratio, piggybacked on neighbor’s probe = 1

21. Dilshad Haleem CST593 summer 2007 Simulation Results of ETX Model Link ETX Link ETX = 1 This implied a perfect link As link ETX increases link quality decrease ETX quantify the link

22. Dilshad Haleem CST593 summer 2007 Conclusion MANETs’ routing protocols are not suitable for WMNs Simulation confirmed that, throughput decreases, when AODV is used in WMNs Routing protocol should be aware of the link condition Implementation of link quality metric (ETX) model in OPNET