Introduction

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2 Outline LAN Introduction IEEE CSMA/CD Ethernet IEEE CSMA/CA Wireless LAN IEEE f IAPP Wireless Protection Access (WPA) vs. IEEE i Enhanced Security 11e QoS 11n Next Generation WLAN (MIMO / Smart Antenna) ETSI HIPERLAN I/II HomeRF 1.0/2.0 IEEE WPAN Bluetooth IEEE Coexistence among 15.1 & 15.4 & 11 IEEE HR-WPAN - UWB (OFDM or DSSS) IEEE LR-WPAN Zigbee Sensor Networks IEEE P1451 IEEE Mesh Network IEEE Wireless MAN (-2004D3 + 16e mobility) Digital Home Working Group (DHWG) IEEE MBWA Wireless LAN-2

3 Wireless LAN-3

4 Introduction to Local Area Networks (LANs) Wireless LAN-4

5 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

6 Global Wireless Standards Wireless LAN-6

7 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

8 LAN Components Computers (Networking devices) Transmission System (Network Cards, Cabling) Wireless LAN-8

9 LAN Extension 路 1 路 2 益 Wireless LAN-9

10 Network Topologies Star Single Star (IEEE VG-AnyLAN, ATM, IEEE WMAN) Multiple Star (Snowflake) (ATM, IEEE WPAN, IEEE LR-WPAN) Bus Single Bus (IEEE CSMA/CD, IEEE Token-Bus) Dual Bus (IEEE DQDB) Tree Ring Single Ring (IEEE Token Ring) Dual Ring (FDDI, FDDI-II) Mesh (ATM, IEEE WPAN, IEEE LR-WPAN) Random (IEEE CSMA/CA) Wireless LAN-10

11 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

12 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

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

14 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

15 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

16 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

17 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

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

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

20 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

21 SDU and PDU Wireless LAN-21

22 IEEE Project 802 Standards IEEE 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 LLC (Logical Link Control) IEEE CSMA/CD (Carrier Sense Multiple Access with Collision Detection IEEE Token-Bus IEEE Token-Ring IEEE DQDB (Distributed Queue Dual Bus) IEEE Broadband Technical Advisory Group IEEE Fiber Optic Technical Advisory Group IEEE Integrated Voice and Data LAN Working Group IEEE Interoperable LAN/MAN Security Wireless LAN-22

23 IEEE Project 802 Standards IEEE CSMA/CA Wireless LAN IEEE a High-Speed Physical Layer in the 5GHz Band IEEE b Higher-Speed Physical Layer Extension in the 2.4 GHz Band IEEE e Medium Access Control (MAC) Enhancements for Quality y of Service (QoS( QoS) (WMM wireless multimedia/ / also named as WME wireless multimedia extension) IEEE f Inter-Access Point Protocol (IAPP) IEEE g Further Higher-Speed Physical Layer Extension in the 2.4 GHz Band IEEE h Spectrum and Transmit Power Management extensions in the 5GHz band in Europe IEEE i Enhanced Security (WPA-PSK PSK preshared key / WPA2.0) IEEE k Radio Resource Management IEEE n Next Generation WLAN ((WWiSE world wide spectrum efficiency vs TGnSync)) IEEE p Wireless Access Vehicular Environment IEEE r Fast Roaming IEEE s ESS Mesh Networking IEEE t Wireless Performance Prediction IEEE u InterWorking with External Networks IEEE v Wireless Network Management (Wireless Switch) IEEE w Protected Management Frame Wireless LAN-23

24 IEEE Project 802 Standards IEEE Demand-Priority (100VG-AnyLAN) IEEE Standard Protocol for Cable-TV Based Broadband Communication Network IEEE Wireless Personal Area Networks Access Method and Physical Layer Specifications IEEE Wireless Personal Area Networks (Bluetooth) IEEE Coexistence IEEE 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 GHz unlicensed band defined by FCC 47 CFR over 2 Gbps IEEE 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 Mesh WPAN SCwng (Wireless Next Generation) IEEE Broadband Wireless Access Method and Physical Layer Specifications IEEE MAC & PHY IEEE e Mobility IEEE Resilient Packet Ring Working Group IEEE Mobile Broadband Wireless Access (MBWA) IEEE Media Independent Handoff Working Group IEEE Wireless Regional Area Networks Wibro (Wireless Internet Broadband Access) - Korea Wireless LAN-24

25 IEEE Project 802 Standards MAC WLAN Wireless LAN-25

26 IEEE Project 802 Standards LLC MAC PHY WLAN WPAN WMAN LR-WPAN Wireless LAN-26

OSI OSI 15% 20% OSI OSI ISO International Standard Organization 1984 OSI Open-data System Interface Reference Model OSI OSI OSI OSI ISO Prototype Prot

OSI OSI OSI 15% 20% OSI OSI ISO International Standard Organization 1984 OSI Open-data System Interface Reference Model OSI OSI OSI OSI ISO Prototype Protocol OSI OSI OSI OSI OSI O S I 2-1 Application