CIS 6930: Workshop Research Introduction and Lab Assignments

CIS 6930: Workshop Research Introduction and Lab Assignments Wireless Measurements: Shao-Cheng Wang ( [email protected] ) Trace Analysis: Wei-jen Hsu ( [email protected] ) Encounter-based Networks: Sapon Tanachaiwiwat ( [email protected] ) Gradient-based routing in Wireless Sensor Networks: Jabed Faruque ( [email protected] ) Instructor: Dr. Helmy 2/5/2007 1

CIS 6930: Workshop I Wireless Measurements Presenter: Shao-Cheng Wang [email protected] Instructor: Dr. Helmy 2/5/2007 2

Agenda Introduction Wireless measurement fundamentals Tools Assignment questions Reference 3

How does a coverage map look like? http://www.ittc.ku.edu/wlan/images.shtml 4

coverage maps (cont’d) 5

Wireless fundamentals: SNR v.s. Distance 6

Wireless fundamentals: SNR v.s. Performance SNR v.s. Delivery ratio (emulator) SNR v.s. Delivery ratio (real measurement) SNR v.s. TCP Tput (real measurement) 7

Tools Site-surveyer: Netstumbler (www.netstumbler.com) – Signal (in –dbm), SNR – AP MAC, SSID 8

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Tools (cont’d) HP iPAQ 10

Tools (cont’d) Bandwidth test – NDT @ UF: http://ndt.server.ufl.edu:7123/ TCP uplink/dnlink speed – Myspeed: http://myvoipspeed.visualware.com/ UDP loss rate, jitter 11

Lab Assignment Coverage Map: – Create a coverage map of your choice: SNR (enhanced with levels, dbm #’s) SNR variations (weather, day/night) Performance map Find holes, additions, tech heterogeneity (11a/b/g/e/n) etc. (please coordinate between groups for the area of interest) – Reason about your choice and the implications of practicability – Observations/Surprises? AP Hunting/Coverage – Locate APs in some specific areas/buildings – Create an AP-specific coverage map – Observations and discussions about the AP planning (evaluation of planning, tradeoffs, applications, etc.) 12

Lab Assignment (cont’d) Bonus questions – Other types of maps? (e.g. war-driving) – Other points of interest (e.g. downtown Gville, oaks mall)? (http://www.digitaldowntown.net/) – How to improve visualization? (http://www.sketchup.com) – How to automate the measurement procedure? (e.g. using campus bus to survey wider areas?) Logistics – Lab #1 starts this week, due 2/26 (3 weeks from today) Come up your plan soon, feel free to discuss with me and other a-group members (email, appointments.) – Come to CSE401 to check out equipments if you want iPAQ 2400 (with Wi-fi, bluetooth built-in) iPAQ 3900 (with gps, bluetooth built-in) *checkout by “per group”, send email for appointment before you come, bring your id. *no overnight loan. everything should be returned by 6pm 13

Reference Simon Byers and Dave Kormann, “802.11b access point mapping,” Communications of the ACM, May 2003. Daniel Aguayo, John Bicket, Sanjit Biswas, Glenn Judd, Robert Morris, “Link-level Measurements from an 802.11b Mesh Network,” SIGCOMM 2004, August 2004 Hiroto Aidal, Yosuke Tamura2, Yoshito Tobe2, Hideyuki Tokudal, “Wireless Packet Scheduling with Signal-to-Noise Ratio Monitoring,” LCN 2000 14