星期日, 2月 26, 2006

802.11

802.11 Metropolitan Wireless Business Models
  • Taipei Model
  • Bay Area Model
  • Philadelphia Model

802.11 Protocol
  • 802.11b/a/g/n
  • 802.11 MAC (pp. 2-88~2-107)
  • 802.11 PCF & DCF
    802.11 RTS & CTS
    802.11 QoS
  • animations (two Applets about CSMA/CA Simulations)

Industry & Products

Features of Skype

1. peer to peer, no server required, therefore, no operation cost like cellular communications
2. overlay, not relying on existing Internet protocols beyond Layer 4, resilient to malfunctions of Internet services
3. scalable, using supernodes among every 500 nodes, adaptive to constant configuration changes
4. high quality codec for crystal voice
5. strong penetration to NAT and firewalls
6. free for now and maybe forever for on-net calls
7. implementation of packet voice
8. consumes reasonable bandwidth, consumes significant CPU
9 . teleconference, voice communications for 5 parties at most
10. millions people online all the times, number keep rising.
11. provide presence like messengers, great feature compared to old phones

星期六, 2月 25, 2006

3-11-2006

Wireless Applications On the Go
Metropolitan Scale Wireless, 802.11S, Mesh Network Design Issues

Wireless Metropolitan Services

遠端照護
無障礙設施(行動導盲)
垃圾車提示
路邊停車
環保稽查
到院前照護(急救病例生理數據)
民眾上網費用收入
民眾VOIP費用收入
婦女夜間乘車安全監控
學童安全
汽車、貴重物品監控
定位廣告推播費用
學童安全



Homework 2-25-2006

停課公告: 因為外出開會, 三月四日停課一次

1. Read the article Paging (and Tracking) Dr. Wi-Fi.
Write down the abstract.

2. Propose 1~3 wireless services that can be depolyed on motropolitan wireless networks. What kind of business model is there?

如果你的作業引用他人文章, 務必註明出處或是網址, 以示尊重他人創作.

References:
1. Wireless Metropolitan Services
2. 學童安全
3. 婦女夜間乘車安全監控
4. 汽車、貴重物品監控
5. Wireless Health Care

上課地點為芳鄰社區資源中心

本學期上課地點為芳鄰社區資源中心
位置: 從『祐生建築研究中心』旁學校後門出去,往金州商店方向就可看到『芳鄰』

Dual Mode Handset

Nokia Launches Dual-Mode 6136 Flip PhoneWi-Fi Cell Phone T-Mobile Ready

1. With voice revenue slowly declining, operators are looking towards content to make up the difference.
2. They're banking on dual-mode convergence as one tool to do so.
3. The additional bandwidth of a Wi-Fi network should encourage mobile subscribers to use more data services, such as Web, e-mail, MMS, music, video, handset TV, etc.
"

Issues of Voice over Wi-Fi

1. 802.11 QoS

absence—until very recently—of a standards-based solution for prioritizing

2. Fast Hand-off between APs

re-authentication between APs takes time such that voice suffers.

Product Solution : "UltraThin" access points (APs) & packet-by-packet micro-management of multiple data streams means that adjacent APs are never broadcasting at the same time

segregate different types of traffic (e.g., voice and data) on different radios, completely eliminating the 'contention' issue or need to prioritize traffic

background:
Wi-Fi—802.11b and 802.11g—there are only three non-overlapping channels

星期六, 2月 18, 2006

Homework 2-18-2006

1. Create your own blog

2. Name a city where metropolitan wireless networks are being
deployed. What are the major services in that city?

reference

Bangladesh City Unwires with Sun-Powered Mesh

tip

How to insert a link at the following comment, please use the following HTML code.

無線網路規劃實例

台北市無線寬頻都市
桃園無線都市
台南縣永康國小校園無線應用
無線社區照護應用

Design Issues of Wireless Applications

Business models

End user devices (diversified)

Infrastructure

Ecology and value chain

Killer Applications

Create your own blog

1. 至 http://www.blogger.com 申請, 請以你的學號 (g/s開頭) 申請免費帳號。主旨欄請用以下格式 "無線通訊網路作業一"
以加速助教登錄作業成績。

2. 請將你的作業寫在你的 blog, 然後到 課程部落格
當次 Homework 的Comment 登錄你的作業blog網址就可以了.
請勿將作業直接寫在 comment
範例

3. Use Gif verification to prevent vandalism.

4. Set Locale & Time Zone

Syllabus for Spring 2006

Textbook

(M) C. Siva Ram Murthy, B. S. Manoj Ad Hoc Wireless Networks: Architectures and Protocols Prentice Hall, 2004. 全華圖書代理進口

Reference
(G) Aura Ganz, Zvi Ganz, Kitti Wongthavarawat Multimedia Wireless Networks, Prentice Hall, 2004.
Behrouz Forouzan TCP/IP Protocol Suite McGraw-Hill,
全華圖書代理進口, 2003.

(F) Behrouz Forouzan (
陳中和、吳秀峰翻譯) TCP/IP 協定精要 (TCP/IP Protocol Suite, 2/e) 2004

(W) Wireless Business News Updates: http://www.wifiplanet.com

使用說明

M2.1 表示 Murthy的書第2.1節

學期課程

1. Trends of Internet Applications and Business models

Peer to peer, VoIP, Wi-Fi, WiMax, M-Commerce

Reading Assignments: handout at Wireless Blog

2. Design of Wireless Applications

Location Based Services, Metropolitan Wireless Networks

3. A Perspective of Wired & Wireless Broadband Networks

802.3, ADSL, Cable Modem, T Lines, SONET, Frame Relay, ATM, FTTx, 802.11 a/b/g, Wireless Mesh, 802.16, 802.16a, 802.15, GPRS, 3G, DTV, DAB, GPS, RFID, Ad Hoc Wireless Network, Wireless Sensor Network

Reading Assignments: M1.1~ M1.8, M1.12, F 3.1~F3.3,

4. Underlying Technology at Physical Layers

Reading Assignments: M1.1~ M1.8, Handout to announce

5. OSI Model and TCP/IP Protocol Suite

Layers in the OSI model, TCP/IP protocol suite, addressing

Reading Assignments: M1.9~ M1.12, F2.1~F2.3, F2.5

6. Ad Hoc Wireless Networks

Issues, MAC & Routing

Reading Assignments: M5.1~M5.3, M6.1~M6.9, M7.1~M7.9