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Outline LAN Introduction IEEE 802.3 CSMA/CD Ethernet IEEE 802.11 CSMA/CA Wireless LAN IEEE 802.11f IAPP Wireless Protection Access (WPA) vs. IEEE 802.11i Enhanced Security 11e QoS 11n Next Generation WLAN (MIMO / Smart Antenna) 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 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? 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 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 Computers (Networking devices) Transmission System (Network Cards, Cabling) Wireless LAN-8

LAN Extension 路 1 路 2 益 Wireless LAN-9

Network Topologies Star 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) Bus Single Bus (IEEE 802.3 CSMA/CD, IEEE 802.4 Token-Bus) Dual Bus (IEEE 802.6 DQDB) Tree Ring 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 B B B A C A C A C E D E D E D Star Ring Dual Ring B D F A B D A B C A C E C E F Bus Tree Dual Bus Wireless LAN-11

Network Topologies A B C D A B C Dual Bus B Dual Bus C B A D A F D H E C Mesh E G Snowflake F Wireless LAN-12

Network Topologies Piconet 2 A Piconet contoller s B Piconet 1 Piconet contoller Mesh Mesh Wireless LAN-13

Network Topologies B G A C F H E D J I A B D... F G H L C E Hub, Switch or Concentrator K M O N Wireless LAN? Bridged Ring Networks Wireless LAN-14

Open System Interconnection (OSI) Model Physical Layer. Responsible for transmission of bit streams across a particular physical transmission medium. Retransmission is not supported. Encoding/Decoding Scrambling/Descrambling Data Link Layer. Responsible for providing reliable data transmission from one node to another. Provides error-free transmission of frames. Network Layer. Concerned with routing data from one network node to another. Provides routing path selection. Establishing/Maintaining/Terminating network connection Transport Layer. Responsible for providing data transfer between two end users at an agreed on level of quality. Establishing/Maintaining/Terminating transport layer connection Wireless LAN-15

Open System Interconnection (OSI) Model Session Layer. Providing services used to organize and synchronize the dialog that takes place between users and to manage the data exchange. Presentation Layer. Responsible for the presentation of information to the network users. Character code translation/ Data conversion Data compression/expansion Encryption/Decryption Application Layer. Provides services to application processes or users. 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 (Application Layer) (Presentation Layer) (Session Layer) (Transport Layer) 路 (Network Layer) (Data Link Layer) (Physical Layer) Wireless LAN-17

Layering Protocols A B X Y 路路路 Wireless LAN-18

Basic Functions of Protocols Encapsulation/Decapsulation Segmentation/Reassembly Connection Establishing Flow Control Error Control Multiplexing/Demultiplexing Wireless LAN-19

Encapsulation/Decapsulation Mechanisms X 料 Y AH 料 PH 料 SH 料 TH 料路 NH 料路 F A C 料 FCS F 串路 Wireless LAN-20

SDU and PDU Wireless LAN-21

IEEE Project 802 Standards IEEE 802.1 High Level Interface 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 IEEE 802.11 CSMA/CA Wireless LAN 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 y of Service (QoS( 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 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 IEEE 802.12 Demand-Priority (100VG-AnyLAN) IEEE 802.14 Standard Protocol for Cable-TV Based Broadband Communication Network IEEE 802.15 Wireless Personal Area Networks Access Method and Physical Layer Specifications 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 (DS-UWB vs MB-OFDM) 3b improve implementation and interoprability of the MAC 3c millimeter-wave wave-based alternative PHY 57-64 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 throughput, and ultra low power ) 4b revisions r and Enhancements IEEE 802.15.5 Mesh WPAN SCwng (Wireless Next Generation) IEEE 802.16 Broadband Wireless Access Method and Physical Layer Specifications IEEE 802.16-2004 2004 MAC & PHY IEEE 802.16e Mobility IEEE 802.17 Resilient Packet Ring Working Group IEEE 802.20 Mobile Broadband Wireless Access (MBWA) IEEE 802.21 Media Independent Handoff Working Group 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 WPAN WMAN LR-WPAN Wireless LAN-26