3Growth rate:Cellular Systems GSM, GSM, CDMA CDMA, , TDMA TDMA
GPRS, EDGE 3G 3G::TD TD, , W W -CDMA CDMA……
WLAN IEEE 802.11HiperLAN
PAN Bluetooth
5LAN and Wireless LAN (WLAN)
?
In early 90’s, IEEE802.11 research group start to define the access method and physical layer specification for Wireless LAN.
?Documented by ISBN 1-55937-052-1?
Version info:
?ANSI/IEEE Std 802.11, 1997,1999 Edition ?
[ISO/IEC 8802-11: 1999]
AP: Access point Emergency Medical Care Distributed WLAN
ESS ：extended service set IESS ：Independent ESS
IEEE 802.3 and 802.11 Protocol stack
Application Application Client
AP
IEEE802.11 standard family (1)
1~2Mbps 802.11a 5GHz 54Mbps 802.11b 2.4GHz 11Mbps
Physical
IR 2.4GHz (FHSS)2.4GHz (DSSS)
5GHz (OFDM)802.11d
802.11 IR 1/2Mbps
802.11 FHSS 1/2Mbps 802.11 DSSS 1/2Mbps 802.11b 5/11Mbps
802.11b MIB update 802.11g >20Mbps
802.11a 6/12/24/36/54 Mbps 802.11h spectrum management
Roaming & Next Gen. WLAN…
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SOURCE: https://www.doczj.com/doc/f42373835.html,
VHF = VERY HIGH FREQUENCY UHF = ULTRA HIGH FREQUENCY SHF = SUPER HIGH FREQUENCY EHF = EXTRA HIGH FREQUENCY
4G CELLULA R 56-100 GHz
3G CELLULA R 1.5-5.2 GHz
1G, 2G CELLULA R
0.4-1.5GHz
UWB 3.1-10.6 GHz
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?Different interframe spacing is used to define priority ?Highest: SIFS ?Medium: PIFS ?
Lowest: DIFS
A
B
D
C
A
B
C
Proxim Harmony 802.11a CardBus Card Intel PRO/Wireless 5000 LAN CardBus Adapter
SMC 802.11a Wireless CardBus Adapter
Actiontec 802.11a Wireless Networking Cards 802.11b PC Card Diagram
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Power Over Ethernet
?
https://www.doczj.com/doc/f42373835.html,/articles/poe
WLAN Scenario 1: PC to PC
Wireless NIC link 2 PCs directly
PC could communicate with each other sharing data Enables information exchange with ease
Wireless LAN PC Card
?Each wireless station and access point has a wireless LAN card ?Provides an interface between an end-user device and radio waves
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WLAN Scenario 2: PC to LAN
?Infrastructure mode ?BSS ?
ESS
?BSS overlapping ?
roaming among APs
E -mail server
WWW server
Radio signal
Security solution
+
Firewall
Internet
Wireless LAN Access Point
Connected to the wired network
Acts as bridge between wireless and wired network Enables high-performance network access
W -NIC
+WLAN bridge
Acts as bridge between 2 WLANs
+
+
+
++
60roaming among APs
among 2 or more networks
3
2
1
frame for WAPI was
TCP/UDP port number 3810 was reserved for WAPI
SMS4 was adopted as one of the encryption
algorithm for WAPI authentication and privacy
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