1. Round Robin vs. Fair Queuing
Internet Sharing Among Multiple Applications
Group 1(b) Gilse George z
Nashid Farhad z
Taimur Ali Khan z

2. Scenario Computer applications that rely on network
File Transfer, P2P, Web Browser, Audio/Video Streaming, Conferencing, Updating
All the applications can run simultaneously and need access to the network/Internet
This access needs to managed

3. Scenario (cont.) Why? Users now-a-days tend to do multitasking.
Application running in background seldom access the Internet (e.g. checking for update, extension etc.)
More and more application are becoming Internet depended (e.g. requires Internet access to function properly)

4. Simulation Specifics Discrete Time Simulation
Visual C
On/Off sources with Poisson Arrival
Packet size: Exponentially distributed around the mean
Inter-arrival time: exponentially distributed around the mean
On/Off Time: exponentially distributed

5. Simulation Specifics (cont.)
Internet Speed
Run simulation for varying speed
Result
Effective BW
Packet Loss (e.g. packets dropped in a finite queue)
Average time of packets in system (excluding dropped packets)

6. Simulation Specifics (cont.)
Queue size = 1000 packets
4 sources:
Application
Type
Avg. Packet Size
BW requirement
File Transfer(FTP)
Balanced
512 bytes
Available
Browser (HTTP)
Bursty
660 bytes
Audio (VoIP- G.711)
Smooth
218 bytes
64kbps
Video (mpeg)
1360 bytes
1Mbps

7. Effective Bandwidth

8. Average Packet Time (ms)

9. Packet Loss 0.1 Mbps 0.05 Mbps Round Robin Fair Queuing Audio 0% 6%
Video
27%
26%
63%
62%

10. Conclusion
As BW becomes less Fair Queuing gives slightly better performance.
As BW becomes less Fair Queuing gives less delay than Round Robin.
Fair Queuing provides slightly better performance regarding packet loss.