Lab

1
Lab 2WLAN performance measurementCS492 Fall
2006(Fri, 10/13)

• Prof. Sue Moon
• Dooyoung Lee
• Haewoon Kwak
• Hyunwoo Chun

2
Objectives

• Measure TCP/UDP throughput varying of the users
  connected to AP
• Same measurement with channel interference
• Compare TCP/UDP throughput without and with
  interference

3
Step 1

• Learn how to use Iperf S/W

4
Iperf manual

• TCP
• server iperf s
• client iperf c server IP addrs option
  values
• UDP
• server iperf s u
• client iperf c server IP addrs u option
  values
• Option values (or parameters)
• i ltvaluegt interval
• o ltfilenamegt output file
• p ltport numbergt port(default is 5001)
• b ltvaluegt bandwidth
• etc..

5
Step 2

• UDP/TCP test
• No interference

6
Step 2-1 UDP test

• TA execute iperf UDP demon
• Iperf s -u
• Students connect to the UDP demon
• Iperf c server IP address u b 11M i 1 gt
  filename.txt
• ltFilename UDP_step number_team number.txtgt
• Experiments
• 1) disconnect your wireless connection to AP
• 2) Team1 connect to AP and iperf UDP demon
• 3) Team1 and Team2 as the same way like
  second step
• 4) Team 1,2,3,4,5 as the same way
• 5) all (team 1 to team 9)
• After each step, you have to upload your result
  file to the server

7
Step 2-2 TCP test

• TA execute iperf TCP demon
• Iperf s
• Students connect to the TCP demon
• Iperf c server IP address i 1 gt
  filename.txt
• ltFilename TCP_step number_team number.txtgt
• Experiments
• 1) disconnect your wireless connection to AP
• 2) Team1 connect to AP and iperf TCP demon
• 3) Team1 and Team2 as the same way like
  second step
• 4) Team 1,2,3,4,5 as the same way
• 5) all (team 1 to team 9)
• After each step, you have to upload your result
  file to the server

8
Step 3

• UDP/TCP test under channel interference

CS-492 new Access Point
9
Step 3-1 and Step 3-2

• Same experiments like Step 2-1(UDP) and 2-2(TCP)
• But file name is different
• UDP test
• Filename UDP_interference_step number_team
  number.txt
• Ex. UDP_interference_1_team 1.txt
• TCP Test
• Filename TCP_interference_step number_team
  number.txt
• Ex. TCP_interference_1_team 1.txt
• After each step, you have to upload your result
  file to the server

10
Step 4 Discussions

• What was the difference between TCP and UDP
  throughput under 802.11b wireless network?
• Difference under number of users connect to AP
• Difference under different channel
• Describe the reason why the throughput didnt
  decrease linear as increasing number of user
• Is there other factors affected the throughput?
• What was the difference between no interference
  and interference environments?

11
Homework 2

• Each group connects to the same AP using two
  wireless LAN cards
• Group 1 team 1, 2
• Group 2 team 3, 4
• Group 3 team 5, 6
• Group 4 team 7, 8, 9
• Send and receive the packets at the same time
  using the Iperf for 1 hour
• Record the date, location, time and throughput in
  an MS Excel file
• Due 1pm on 10/19 no delay permitted