星期日, 4月 30, 2006

WLAN Regulations

You can use this WLAN Link Planner for link budget, this reference for Part 15.247, and this EIRP calculator.

Installing Wi-Fi Antennas

Safety Advice- If you are mounting an antenna outdoors make sure you have fitted a lightning arrestor! The last thing you want is thousands and thousands of volts of the good stuff hitting your WLAN equipment and computer network.

Regulatory Advice - Make sure you are not exceeding the maximum power for WLAN networks. There is a limit of 20Dbi on all 802.11b equipment.

<full article>

星期四, 4月 20, 2006

Is Wi-Fi Roaming Really Seamless?

read this article

Although it takes only 68 ms to switch to an AP from another,
it can disrupt applications up to 5 seconds.

UMA Follow-Up

Placing F/MC Under Enterprise Control
  • Alternative to UMA

F/MC Watch: VoIP Fallout from CTIA
  • Kyocera demos dual-mode CDMA/Wi-Fi handset with Boingo
  • Boingo partners with Kineto to extend UMA service to hotspots

星期日, 4月 02, 2006

Homework 4-1-2006 Mobile Social Software, Part 2

Pick the assigned service from the list.
Analyze the service based on
  • technology
  • what it works
  • business models
  • trends
Prepare 5~10 slides to turn in your homework. Please mail it to
yjchang at cycu dot edu dot tw before next time we weet in class.

參閱簡報製作原則
如何使用線上學術資源

星期六, 4月 01, 2006

Read this blog using Google Reader

go

Try others such as

  • news.yam.com
  • 中時電子報
  • New York Times

sites that use google maps

Take a look at the following site:
HousingMaps
Google Maps Transparencies
Google Maps Nighttime!
Track visitors to your website
Google Map links for Unesco World Heritage Sites
Frappr

CSMA/CA & 802.11

802.11 PCF & DCF
802.11 RTS & CTS
802.11 QoS

animations (two Applets about CSMA/CA Simulations)
http://wps.aw.com/aw_kurose_network_3/0,9212,1406346-,00.html

packet radio with Aloha

packet radio with Aloha in Lectures 13 & 14 of MIT Data Communication Networks Course

We will also cover the wireless location privacy protection as discussed in the paper by Schilit et al.

evolution of contention based protocols:
1. ALOHA
2. CSMA (Carrier Sense Multiple Access)
3. CSMA/CD (collision detection) -> IEEE 802.3 (Ethernet, 100M, 1Gbps)

OSI Reference Model

Computer Networks
OSI Reference Model
(Lecture 1 in Ref.)

Text: 1.9~1.12

wireless applications for Ticketing

demo