1. SRI International 1 A Simulation Comparison of TBRPF, OLSR, and AODV Richard Ogier SRI International ogier@erg.sri.com July 2002

2. SRI International 2 Protocols Simulated AODV - for ns-2.1b8a –Available from http://www.cs.ucsb.edu/~eroyer/aodv.html TBRPF - for ns-2.1b8 (compliant with version 04 draft) –Available from http://www.erg.sri.com/projects/tbrpf/sourcecode.html –Uses same ‘C’ module as our Linux implementation. OLSR - for ns-2.1b7 (compliant with version 03 draft) –Available from http://hipercom.inria.fr/olsr/ –Bug affecting packet size was fixed. In all protocols, link-layer failure notification was NOT used, and packets could not be retrieved from the link layer (interface queue). ARP was bypassed for both TBRPF and OLSR, since MAC addresses can be obtained from received routing packets.

3. SRI International 3 Simulation Model ns-2 version 2.1b8 WaveLAN IEEE 802.11 MAC with rate 2Mb/s and range 250m 50 and 100 nodes Two area sizes: 670m x 670m and 1500m x 300m Mobility model: No mobility and random waypoint model with 0 pause time and maximum speed 20 m/s. 20 simultaneous CBR traffic streams: –Source and destination of each stream are selected randomly –Duration of each stream is 30 seconds –Size of each data packet is 512 bytes –Packet generation rate per stream is increased from 2 to 8 packets/s Each simulation was run for 500 simulated seconds.

4. SRI International 4 Performance Measures The following measures were plotted for increasing packet generation rates: –percent of data packets delivered –average end-to-end delay –total routing control traffic in kbytes, including IP/MAC headers (divide by 500 to get kbytes/sec). –normalized path length (average ratio of actual hops to minimum hops)

5. SRI International 5 Simulation comparison of TBRPF, OLSR, and AODV 100 nodes, 20 sources, 670x670 area, no mobility DELAY PERCENT DELIVERED ROUTING LOAD PATH LENGTH

6. SRI International 6 Simulation comparison of TBRPF, OLSR, and AODV 100 nodes, 20 sources, 670x670 area, max speed 20mps DELAY PERCENT DELIVERED ROUTING LOAD PATH LENGTH

7. SRI International 7 Simulation comparison of TBRPF, OLSR, and AODV 100 nodes, 20 sources, 1500x300 area, no mobility DELAY PERCENT DELIVERED ROUTING LOAD PATH LENGTH

8. SRI International 8 Simulation comparison of TBRPF, OLSR, and AODV 100 nodes, 20 sources, 1500x300 area, max speed 20mps DELAY PERCENT DELIVERED ROUTING LOAD PATH LENGTH

9. SRI International 9 Simulation comparison of TBRPF, OLSR, and AODV 50 nodes, 20 sources, 670x670 area, no mobility DELAY PERCENT DELIVERED ROUTING LOAD PATH LENGTH

10. SRI International 10 Simulation comparison of TBRPF, OLSR, and AODV 50 nodes, 20 sources, 670x670 area, max speed 20mps DELAY PERCENT DELIVERED ROUTING LOAD PATH LENGTH

11. SRI International 11 Simulation comparison of TBRPF, OLSR, and AODV 50 nodes, 20 sources, 1500x300 area, no mobility PATH LENGTH DELAY PERCENT DELIVERED ROUTING LOAD

12. SRI International 12 Simulation comparison of TBRPF, OLSR, and AODV 50 nodes, 20 sources, 1500x300 area, max speed 20mps DELAY PERCENT DELIVERED ROUTING LOAD PATH LENGTH

13. SRI International 13 Summary of simulation results In every scenario, TBRPF achieved a higher delivery percentage (up to 15% higher) than OLSR. TBRPF also achieved a higher delivery percentage (up to 15% higher) than AODV in all scenarios with no mobility, and in all scenarios using the square (670x670) area with the lower packet rates (2 and 4 packets/s). For the long rectangular (1500x300) area, AODV achieved a higher delivery percentage (up to 5% higher) than TBRPF. In every scenario, TBRPF generated less routing control traffic than the other protocols: up to 60% less than OLSR and up to 48% less than AODV. This is despite the fact that TBRPF sends HELLOs twice as frequently as OLSR. In every scenario, TBRPF used the shortest paths (except nearly shortest in some cases with the higher packet rates). In every scenario, AODV used paths that were 12-20% longer on average than TBRPF. TBRPF usually had the best or nearly best delay.

14. SRI International 14 Remarks This study did not use link-layer notification. It is important to also compare the protocols with link-layer notification, since this allows one to achieve a delivery fraction close to 100%. A comparison of TBRPF with AODV using link-layer notification can also be found at the TBRPF web site. That comparison also compares the protocols with 40 sources (which gives TBRPF more advantage). Although control traffic is not a quality-of-service measure, a routing protocol that generates less control traffic and uses shorter paths: –uses less energy, –is more likely to scale to a larger number of nodes, –is more likely to perform well in lower bandwidth radios such as those used by the military.

15. SRI International 15 Protocol parameters used TBRPF used the following parameter values: –HELLO_INTERVAL = 1 –NBR_HOLD_COUNT = 3 –NBR_HOLD_TIME = 3 –HELLO_ACQUIRE_COUNT = 2 –HELLO_ACQUIRE_WINDOW = 3 –MIN_UPDATE_INTERVAL = 2 –PERIODIC_UPDATE_INTERVAL = 6 –TOP_HOLD_TIME = 15 –NON_REPORT_PENALTY = 1.01

16. SRI International 16 Protocol parameters used (cont.) OLSR used the following parameter values: –HELLO_INTERVAL = 2 –TC_INTERVAL = 5 –PACKET_JITTER = HELLO_JITTER = TC_JITTER = 0.5 –NEIGHBOR_HOLD_TIME = 6 –HELLO_ACQUIRE_COUNT = 2 –TOPOLOGY_HOLD_TIME = 16 –DUPLICATE_HOLD_TIME = 60 –HOLDBACK_TIME = 0