Lab 2 WLAN performance measurement CS 492 Fall

Lab #2 WLAN performance measurement CS 492 Fall 2006 (Fri, 10/13) Prof. Sue Moon Dooyoung Lee Haewoon Kwak Hyunwoo Chun

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 2

Step 1: • Learn how to use Iperf S/W 3

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 <value> : interval o <filename> : output file p <port number> : port(default is 5001) b <value> : bandwidth etc. . 4

Step 2: • UDP/TCP test – No interference 5

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 11 M –i 1 > “filename. txt” <Filename : UDP_step number_team number. txt> • Experiments – 1) : disconnect your wireless connection to AP – 2) : Team#1 connect to AP and iperf UDP demon – 3) : Team#1 and Team#2 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” 6

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 > “filename. txt” <Filename : TCP_step number_team number. txt> • Experiments – 1) : disconnect your wireless connection to AP – 2) : Team#1 connect to AP and iperf TCP demon – 3) : Team#1 and Team#2 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 3: • UDP/TCP test under channel interference CS-492 new Access Point 8

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” 9

Step 4: Discussions • What was the difference between TCP and UDP throughput under 802. 11 b wireless network? – Difference under number of users connect to AP – Difference under different channel • Describe the reason why the throughput didn’t decrease linear as increasing number of user – Is there other factors affected the throughput? • What was the difference between no interference and interference environments? 10

Homework #2 • Each group connects to the same AP using two Embedded wireless card wireless LAN cards – – Group 1 2 3 4 : : team #1, #3, #5, #7, #2 #4 #6 #8, #9 AP Linksys wireless card • 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 1 pm on 10/19 : no delay permitted 11