電腦通訊網路(1)

電腦通訊網路 (1)
Outline
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LAN Introduction
IEEE 802.3 CSMA/CD Ethernet
IEEE 802.11 CSMA/CA Wireless LAN
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ETSI HIPERLAN I/II
HomeRF 1.0/2.0
IEEE 802.15.1 WPAN – Bluetooth
IEEE 802.15.2 Coexistence among 15.1 & 15.4 & 11
IEEE 802.15.3 HR-WPAN - UWB (OFDM or DSSS)
IEEE 802.15.4 LR-WPAN – Zigbee
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IEEE 802.11f IAPP
Wireless Protection Access (WPA) vs. IEEE 802.11i Enhanced Security
11e QoS
11n Next Generation WLAN (MIMO / Smart Antenna)
Sensor Networks
IEEE P1451
IEEE 802.15.5 Mesh Network
IEEE 802.16 Wireless MAN (-2004D3 + 16e mobility)
Digital Home Working Group (DHWG)
IEEE 802.20 MBWA
Wireless LAN-2
Wireless LAN-3
Introduction to
Local Area Networks (LANs)
Wireless LAN-4
What is a LAN ?
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A LAN is a data communication system
allowing a number of independent devices
to communicate directly with each other,
within a moderately sized geographic area
over a physical communications channel of
moderate data rates.
PAN ?
MAN ?
WAN ?
Wireless LAN-5
Global Wireless Standards
Wireless LAN-6
Basic Requirements of a LAN
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Data rate of 1 to 1000 Mbps
Geographic distances spanning at most 1-5 km
Ability to support several hundred independent devices
Minimal dependence on any centralized components or
control
Efficient use of shared resources, including the network
channel
Stability under high load
Fair access (bandwidth, delay) to the network by all devices
Reliability and good error characteristics
Easy installation, reconfiguration and maintenance
Low cost
Wireless LAN-7
LAN Components
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Computers (Networking devices)
Transmission System (Network Cards, Cabling)
工作站
工作站
傳輸媒介:
同軸電纜, 雙絞線, 光纖, radio
工作站
工作站
工作站
Wireless LAN-8
LAN Extension
網路區段 2
網路區段 1
訊號增益器
Wireless LAN-9
Network Topologies
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Star
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Bus
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Single Bus (IEEE 802.3 CSMA/CD, IEEE 802.4 Token-Bus)
Dual Bus (IEEE 802.6 DQDB)
Tree
Ring
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Single Star (IEEE 802.12 100VG-AnyLAN, ATM, IEEE 802.16
WMAN)
Multiple Star (Snowflake) (ATM, IEEE 802.15.1 WPAN, IEEE
802.15.4 LR-WPAN)
Single Ring (IEEE 802.5 Token Ring)
Dual Ring (FDDI, FDDI-II)
Mesh (ATM, IEEE 802.15.1 WPAN, IEEE 802.15.4 LR-WPAN)
Random (IEEE 802.11 CSMA/CA)
Wireless LAN-10
Network Topologies
C
A
E
Star
C
A
C
A
D
E
B
B
B
E
D
Ring
D
Dual Ring
A
D
B
F
D
B
A
A
C
Bus
E
C
E
Tree
B
C
F
Dual Bus
Wireless LAN-11
Network Topologies
A
A
B
B
C
D
C
Dual Bus
Dual Bus
B
B
A
E
Mesh
A
D
H
E
D
F
C
C
F
G
Snowflake
Wireless LAN-12
Network Topologies
Piconet 2
A
B
Piconet
contoller
s
Piconet 1
Piconet
contoller
Mesh
Mesh
Wireless LAN-13
Network Topologies
G
B
橋接器
C
A
H
F
A
E
J
D
I
H
B
D
F
...
G
C
E
橋接器
橋接器
L
Hub, Switch or Concentrator
M
K
O
N
Wireless LAN ?
Bridged Ring Networks
Wireless LAN-14
Open System Interconnection
(OSI) Model
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Physical Layer.
Layer Responsible for transmission of bit streams across a
particular physical transmission medium. Retransmission is not
supported.
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Data Link Layer.
Layer Responsible for providing reliable data transmission
from one node to another. Provides error-free transmission of frames.
Network Layer.
Layer Concerned with routing data from one network node
to another. Provides routing path selection.
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Encoding/Decoding
Scrambling/Descrambling
Establishing/Maintaining/Terminating network connection
Transport Layer.
Layer Responsible for providing data transfer between two
end users at an agreed on level of quality.
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Establishing/Maintaining/Terminating transport layer connection
Wireless LAN-15
Open System Interconnection
(OSI) Model
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Session Layer.
Layer Providing services used to organize and
synchronize the dialog that takes place between users and to
manage the data exchange.
Presentation Layer.
Layer Responsible for the presentation of information
to the network users.
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Character code translation/ Data conversion
Data compression/expansion
Encryption/Decryption
Application Layer.
Layer Provides services to application processes or
users.
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File Transfer Protocol (FTP)
Remote Login (Telnet)
Transaction Server
Network Management
WWW Server/VoD Server ….
Wireless LAN-16
Open System Interconnection
(OSI) Model - Seven Layers
應用層 (Application Layer)
表達層 (Presentation Layer)
會議層 (Session Layer)
傳輸層 (Transport Layer)
網路層 (Network Layer)
鏈結層 (Data Link Layer)
實體層 (Physical Layer)
Wireless LAN-17
Layering Protocols
系統 A
系統 B
應用軟體 Y
應用軟體 X
應用層
應用層通訊協定
應用層
表達層
表達層通訊協定
表達層
會議層
會議層通訊協定
會議層
傳輸層
傳輸層通訊協定
傳輸層
網路層
網路層通訊協定
網路層
鏈結層
鏈結層通訊協定
鏈結層
實體層
實體層通訊協定
實體層
傳輸媒介
Wireless LAN-18
Basic Functions of Protocols
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Encapsulation/Decapsulation
Segmentation/Reassembly
Connection Establishing
Flow Control
Error Control
Multiplexing/Demultiplexing
Wireless LAN-19
Encapsulation/Decapsulation
Mechanisms
往下送時訊框包裝
往上送時訊框拆裝
應用軟體 X
應用層
AH
表達層
鏈結層
實體層
NH
F A C
應用層
表達層
會議層
傳輸層
資料
TH
網路層
資料
資料
SH
傳輸層
應用軟體 Y
資料
PH
會議層
資料
資料
資料
位元串
網路層
FCS F
鏈結層
實體層
通訊路徑
Wireless LAN-20
SDU and PDU
Wireless LAN-21
IEEE Project 802 Standards
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IEEE 802.1 High Level Interface
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IEEE 802.1D Local Bridge (Spanning Tree Algorithm)
IEEE 802.1G Remote Bridge
IEEE 802.1P Traffic Class Expediting and Dynamic Multicast Filtering
IEEE 802.1Q Virtual LANs
IEEE 802.1X Port Based Network Access Control
IEEE 802.2 LLC (Logical Link Control)
IEEE 802.3 CSMA/CD (Carrier Sense Multiple Access with Collision
Detection
IEEE 802.4 Token-Bus
IEEE 802.5 Token-Ring
IEEE 802.6 DQDB (Distributed Queue Dual Bus)
IEEE 802.7 Broadband Technical Advisory Group
IEEE 802.8 Fiber Optic Technical Advisory Group
IEEE 802.9 Integrated Voice and Data LAN Working Group
IEEE 802.10 Interoperable LAN/MAN Security
Wireless LAN-22
IEEE Project 802 Standards
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IEEE 802.11 CSMA/CA Wireless LAN
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IEEE 802.11a High-Speed Physical Layer in the 5GHz Band
IEEE 802.11b Higher-Speed Physical Layer Extension in the 2.4 GHz Band
IEEE 802.11e Medium Access Control (MAC) Enhancements for Quality of Service (QoS)
(WMM wireless multimedia/ also named as WME wireless multimedia extension)
IEEE 802.11f Inter-Access Point Protocol (IAPP)
IEEE 802.11g Further Higher-Speed Physical Layer Extension in the 2.4 GHz Band
IEEE 802.11h Spectrum and Transmit Power Management extensions in the 5GHz band in
Europe
IEEE 802.11i Enhanced Security (WPA-PSK preshared key / WPA2.0)
IEEE 802.11k Radio Resource Management
IEEE 802.11n Next Generation WLAN ((WWiSE world wide spectrum efficiency vs TGnSync))
IEEE 802.11p Wireless Access Vehicular Environment
IEEE 802.11r Fast Roaming
IEEE 802.11s ESS Mesh Networking
IEEE 802.11t Wireless Performance Prediction
IEEE 802.11u InterWorking with External Networks
IEEE 802.11v Wireless Network Management (Wireless Switch)
IEEE 802.11w Protected Management Frame
Wireless LAN-23
IEEE Project 802 Standards
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IEEE 802.12 Demand-Priority (100VG-AnyLAN)
IEEE 802.14 Standard Protocol for Cable-TV Based Broadband Communication Network
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IEEE 802.15 Wireless Personal Area Networks Access Method and Physical Layer Specifications
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IEEE 802.15.1 Wireless Personal Area Networks (Bluetooth)
IEEE 802.15.2 Coexistence
IEEE 802.15.3 WPAN Higher Rate
3a higher speed PHY enhancement amendment for imaging and multimedia
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multimedia (DS(DS-UWB vs MBMB-OFDM)
3b improve implementation and interoprability of the MAC
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3c millimeter„
millimeter-wavewave-based alternative PHY
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5757-64 GHz unlicensed band defined by FCC 47 CFR 15.255
over 2 Gbps
IEEE 802.15.4 WPAN Low Rate (Zigbee
(Zigbee)) (4a is on going)
4a alternative PHY (high precision ranging / location (<1 meter accuracy), high aggregate
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aggregate throughput, and ultra low power )
4b revisions and Enhancements
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IEEE 802.15.5 Mesh WPAN
SCwng (Wireless Next Generation)
IEEE 802.16 Broadband Wireless Access Method and Physical Layer Specifications
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IEEE 802.16802.16-2004 MAC & PHY
IEEE 802.16e Mobility
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IEEE 802.17 Resilient Packet Ring Working Group
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IEEE 802.20 Mobile Broadband Wireless Access (MBWA)
IEEE 802.21 Media Independent Handoff Working Group
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IEEE 802.22 Wireless Regional Area Networks
Wibro (Wireless Internet Broadband Access) - Korea
Wireless LAN-24
IEEE Project 802 Standards
MAC
WLAN
Wireless LAN-25
IEEE Project 802 Standards
LLC
MAC
PHY
WLAN
WMAN
WPAN
LR-WPAN
Wireless LAN-26
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