Wireless# Guide to Wireless Communications. Objectives

Save this PDF as:
 WORD  PNG  TXT  JPG

Size: px
Start display at page:

Download "Wireless# Guide to Wireless Communications. Objectives"

Transcription

1 Wireless# Guide to Wireless Communications Chapter 7 Low-Speed Wireless Local Area Networks Objectives Describe how WLANs are used List the components and modes of a WLAN Describe how an RF WLAN works Explain the differences between IR, IEEE , and IEEE b WLANs Outline the user mobility features offered by IEEE networks Wireless# Guide to Wireless Communications 2 1

2 WLAN Applications Wireless networks are increasing in popularity Installing cabling is inconvenient and very expensive Wireless networks solve this problem With a wireless network Multiple users can share a single Internet connection Wireless residential gateway Device that combines a router, Ethernet switch, and wireless access point Also allows Internet and printer sharing Wireless# Guide to Wireless Communications 3 WLAN Components Minimal hardware needed for a WLAN Computer ISP (???) Wireless network interface card Access point (AP) Wireless# Guide to Wireless Communications 4 2

3 Wireless Network Interface Card Network interface card (NIC) Allows a computer to be connected to a network Wireless NIC Connects a computer to a network without cables Most often a separate card Mini PCI Small card that is functionally equivalent to a standard PCI expansion card Used with notebook computers Wireless# Guide to Wireless Communications 5 Wireless Network Interface Card (continued) Wireless# Guide to Wireless Communications 6 3

4 Wireless Network Interface Card (continued) Smaller devices have two options for wireless NICs Optional sled Includes a Type II PC Card slot and battery Compact flash (CF) card or secure digital (SD) card Smaller and consume less power Transmit and receive with lower power levels Intel Centrino chipset Integrates all of the functions of a wireless NIC Mounted directly on the motherboard Wireless# Guide to Wireless Communications 7 Wireless Network Interface Card (continued) Wireless# Guide to Wireless Communications 8 4

5 Access Points Access point (AP) Provides wireless LAN devices with a point of access into a wired network AP parts Radio transceiver Antenna RJ-45 wired network interface port AP functions Wireless communications base station Bridge between the wireless and wired networks Wireless# Guide to Wireless Communications 9 Access Points (continued) Wireless# Guide to Wireless Communications 10 5

6 Access Points (continued) The range of an AP is approximately 115 meters Dynamic rate selection AP will automatically select the highest possible data rate for transmission Depending on the strength and quality of the signal An AP can generally support over 100 users Power over Ethernet (PoE) DC power is delivered to the AP through the unused wires in a standard UTP Ethernet cable Wireless# Guide to Wireless Communications 11 WLAN Modes Ad hoc mode Infrastructure mode Wireless# Guide to Wireless Communications 12 6

7 Ad Hoc Mode Also known as peer-to-peer mode Formal name: Independent Basic Service Set (IBSS) mode Wireless clients communicate directly among themselves without using an AP Quick and easy setup of a wireless network Drawback is that wireless clients can only communicate among themselves Wireless# Guide to Wireless Communications 13 Ad Hoc Mode (continued) Wireless# Guide to Wireless Communications 14 7

8 Infrastructure Mode Also known as the Basic Service Set (BSS) Consists of wireless clients and an AP Extended Service Set (ESS) Two or more BSS wireless networks installed in same area Provides users with uninterrupted mobile access to the network All wireless clients and APs must be part of the same network For users to be able to roam freely Wireless# Guide to Wireless Communications 15 Infrastructure Mode (continued) Wireless# Guide to Wireless Communications 16 8

9 Infrastructure Mode (continued) Can be difficult to manage one large network Performance and security may also be adversely affected Subnets Network units that contain fewer computers In an ESS divided into subnets A mobile user might not be able to freely roam between APs Wireless# Guide to Wireless Communications 17 Wireless LAN Standards and Operation Most WLANs are based on these same initial IEEE standards Wireless# Guide to Wireless Communications 18 9

10 IEEE Standards standard Defines a local area network that provides cable-free data access for clients That are either mobile or in a fixed location At a rate of either 1 or 2 Mbps Using either diffused infrared or RF transmission Specifies that the features of a WLAN be transparent to the upper layers of the TCP/IP protocol stack Or the OSI protocol model Wireless# Guide to Wireless Communications 19 IEEE Standards (continued) Wireless# Guide to Wireless Communications 20 10

11 IEEE Infrared WLAN Standard IEEE standards outline the specifications for infrared as well as RF WLANs Infrared specification is based on diffused transmissions PHY layer sublayers Physical Medium Dependent (PMD) Physical Layer Convergence Procedure (PLCP) Wireless# Guide to Wireless Communications 21 IEEE Infrared WLAN Standard (continued) Wireless# Guide to Wireless Communications 22 11

12 IEEE Infrared WLAN Standard (continued) Diffused infrared PHY layer convergence procedure standards Reformats the data received from the MAC layer Into a frame that the PMD sublayer can transmit Frame s size is not measured in bits but in time slots Start frame delimiter for infrared is always 1001 Data rate value determines transmission speed Direct current level adjustment Contains a pattern of infrared pulses Allows receiving device to determine the signal level Wireless# Guide to Wireless Communications 23 IEEE Infrared WLAN Standard (continued) Wireless# Guide to Wireless Communications 24 12

13 IEEE Infrared WLAN Standard (continued) Wireless# Guide to Wireless Communications 25 IEEE Infrared WLAN Standard (continued) Diffused infrared physical medium dependent standards PMD translates the binary 1s and 0s of the frame into light pulses that are used for transmission PMD transmits data using a series of light impulses 16-pulse position modulation (16-PPM) Translates four data bits into 16 light impulses 4-pulse position modulation (4-PPM) Used for transmissions at 2 Mbps Each time slot is 250 ns (nanoseconds) Wireless# Guide to Wireless Communications 26 13

14 IEEE Infrared WLAN Standard (continued) Wireless# Guide to Wireless Communications 27 IEEE Infrared WLAN Standard (continued) Wireless# Guide to Wireless Communications 28 14

15 IEEE b Standard Added two higher speeds, 5.5 Mbps and 11 Mbps Specified RF and direct sequence spread spectrum (DSSS) as the only transmission technology Also known as Wi-Fi Physical layer Divided into two parts Physical Medium Dependent (PMD) Physical Layer Convergence Procedure (PLCP) Wireless# Guide to Wireless Communications 29 IEEE b Standard (continued) Physical layer convergence procedure standards Based on direct sequence spread spectrum (DSSS) Must reformat the data received from the MAC layer into a frame that the PMD sublayer can transmit PLCP frame is made up of three parts: the preamble, the header, and the data Frame preamble and header are always transmitted at 1 Mbps Allows communication between slower and faster devices Wireless# Guide to Wireless Communications 30 15

16 IEEE b Standard (continued) Wireless# Guide to Wireless Communications 31 IEEE b Standard (continued) Physical medium dependent standards Translate the binary 1s and 0s of the frame into radio signals that can be used for transmission b standard uses the Industrial, Scientific, and Medical (ISM) band Specifies 14 available frequencies, beginning at GHz and incrementing by.005 GHz PMD can transmit the data at 11,5.5, 2,or 1 Mbps For transmissions at 1 Mbps, two-level differential binary phase shift key (DBPSK) is used Wireless# Guide to Wireless Communications 32 16

17 IEEE b Standard (continued) Wireless# Guide to Wireless Communications 33 IEEE b Standard (continued) Physical medium dependent standards (continued) Transmissions at 2, 5.5, and 11 Mbps use differential quadrature phase shift keying To transmit at rates above 2 Mbps, Complementary Code Keying (CCK) is used A table containing 64 8-bit code words Media access control layer b Data Link layer consists of two sublayers Logical Link Control (LLC) Media Access Control (MAC) Wireless# Guide to Wireless Communications 34 17

18 IEEE b Standard (continued) Media access control layer (continued) Changes for b WLANs are confined to the MAC layer On a WLAN, all devices share the same RF spectrum Distributed coordination function Channel access methods can prevent collisions Carrier sense multiple access with collision avoidance (CSMA/CA) Based on CSMA/CD Wireless# Guide to Wireless Communications 35 IEEE b Standard (continued) Wireless# Guide to Wireless Communications 36 18

19 IEEE b Standard (continued) Distributed coordination function (continued) CSMA/CD is designed to handle collisions CSMA/CA attempts to avoid collisions altogether With contention-based channel access methods Most collisions occur after a device completes its transmission CSMA/CA makes all devices wait a random amount of time CSMA/CA also reduces collisions by using explicit packet acknowledgment (ACK) Wireless# Guide to Wireless Communications 37 IEEE b Standard (continued) Wireless# Guide to Wireless Communications 38 19

20 IEEE b Standard (continued) Distributed coordination function (continued) Additional mechanisms to reduce collisions Request to Send/Clear to Send (RTS/CTS) protocol Fragmentation Polling Another type of channel access method Each computer is asked if it wants to transmit Polling effectively eliminates collisions Point coordination function (PCF) AP serves as the polling device Wireless# Guide to Wireless Communications 39 IEEE b Standard (continued) Wireless# Guide to Wireless Communications 40 20

21 IEEE b Standard (continued) Wireless# Guide to Wireless Communications 41 IEEE b Standard (continued) Association and reassociation Allow a client to join a WLAN and stay connected Association begins with the client scanning the airwaves Types of scanning Passive scanning Client listening to each available channel for a set period of time Client listens for a beacon frame transmitted from all available APs Frame includes the AP s SSID Wireless# Guide to Wireless Communications 42 21

22 IEEE b Standard (continued) Association and reassociation (continued) Types of scanning (continued) Active scanning Client sends a probe frame to each channel Client then waits for the probe response frame Associate request frame Includes the client s capabilities and supported rates Associate response frame Sent by the AP Contains a status code and client ID number for that client Wireless# Guide to Wireless Communications 43 IEEE b Standard (continued) Association and reassociation (continued) Reassociation Client may drop the connection with one AP and reestablish the connection with another Necessary when mobile clients roam beyond the coverage area of one AP Client sends a reassociation request frame to new AP AP sends back a reassociation response frame New AP sends a disassociation frame to old AP Wireless# Guide to Wireless Communications 44 22

23 IEEE b Standard (continued) Wireless# Guide to Wireless Communications 45 IEEE b Standard (continued) Power management Most clients in a WLAN are portable devices To conserve battery power, they can go into sleep mode When a client is part of a WLAN, it must remain fully powered Power management allows the mobile client s NIC to be off as much as possible But still not miss out on data transmissions The key to power management is synchronization Wireless# Guide to Wireless Communications 46 23

24 IEEE b Standard (continued) Power management (continued) When a mobile b client goes into sleep mode, the AP is informed of the change AP temporarily stores the synchronized frames (this function is called buffering) At predetermined times, the AP sends out a beacon frame to all clients Containing the traffic indication map (TIM) Traffic indication map (TIM) List of clients with buffered frames waiting at the AP Wireless# Guide to Wireless Communications 47 IEEE b Standard (continued) Wireless# Guide to Wireless Communications 48 24

25 IEEE b Standard (continued) MAC frame formats Three types of MAC frame formats Management frames Used to set up the initial communications Control frames Provide assistance in delivering the frames that contain the data Data frames Carry the information to be transmitted to the destination client Wireless# Guide to Wireless Communications 49 IEEE b Standard (continued) Wireless# Guide to Wireless Communications 50 25

26 IEEE b Standard (continued) Wireless# Guide to Wireless Communications 51 IEEE b Standard (continued) Wireless# Guide to Wireless Communications 52 26

27 Distributed Coordination Function Rules standard defines a number of interframe spaces (IFS) To handle the contention for the medium Interframe space types Short interframe space (SIFS) Distributed coordination function interframe space (DIFS) Basic rules of communication in an network Device that wants to transmit begins listening for an RF signal Wireless# Guide to Wireless Communications 53 Distributed Coordination Function Rules (continued) Wireless# Guide to Wireless Communications 54 27

28 Distributed Coordination Function Rules (continued) Basic rules of communication in an network (continued) Size of a frame includes both the length of time necessary to send the data plus an SIFS After receiving an ACK, the transmitting client begins to wait a random backoff interval If the transmitting device does not receive an ACK within the SIFS It is allowed to maintain control of the medium If the frame was acknowledged correctly Transmitting device listens to the medium while waiting its backoff interval Wireless# Guide to Wireless Communications 55 Distributed Coordination Function Rules (continued) Wireless# Guide to Wireless Communications 56 28

29 Distributed Coordination Function Rules (continued) In the case of traffic in the medium Client A is using DSSS with a backoff interval of 3 While Client B has a backoff interval of only 2 Client A transmits its first frame Client B detects traffic and waits Both devices begin carrier sensing during second DIFS At the end, clients A and B begin their backoff interval Client B will finish its backoff interval before Client A Then begins transmitting its first packet Next time, client A will wait only for 1 interval Wireless# Guide to Wireless Communications 57 Distributed Coordination Function Rules (continued) Wireless# Guide to Wireless Communications 58 29

30 Summary The wireless technology that attracts the most attention today Radio frequency (RF) wireless local area networks (WLANs) Wireless NIC performs same functions as wired NIC Access points parts Antenna Radio transceiver RJ-45 wired network interface Wireless# Guide to Wireless Communications 59 Summary (continued) Data can be sent and received in an RFWLAN either in ad hoc or infrastructure mode IEEE standard defines a local area network that provides cable-free data access standard uses an access method known as the distributed coordination function (DCF) Specifies that carrier sense multiple access with collision avoidance (CSMA/CA) be used standard provides for an optional polling function known as point coordination function (PCF) Wireless# Guide to Wireless Communications 60 30

31 Summary (continued) Mobile WLAN devices often depend on batteries as their primary power source Sleep mode conserves battery power standard specifies three different types of MAC frame formats Management frames Control frames Data frames Wireless# Guide to Wireless Communications 61 31

Guide to Wireless Communications, Third Edition. Objectives

Guide to Wireless Communications, Third Edition. Objectives Guide to Wireless Communications, Third Edition Chapter 7 Low-Speed Wireless Local Area Networks Objectives Describe how WLANs are used List the components and modes of a WLAN Describe how an RF WLAN works

More information

Chapter 3.1 Acknowledgment:

Chapter 3.1 Acknowledgment: Chapter 3.1 Acknowledgment: This material is based on the slides formatted by Dr Sunilkumar S. manvi and Dr Mahabaleshwar S. Kakkasageri, the authors of the textbook: Wireless and Mobile Networks, concepts

More information

Wireless Protocols. Training materials for wireless trainers

Wireless Protocols. Training materials for wireless trainers Wireless Protocols Training materials for wireless trainers Goals The goal of this lecture is to introduce: IEEE wireless protocols coverage 802.11 radio protocols terminology WiFi modes of operation details

More information

WiFi Networks: IEEE b Wireless LANs. Carey Williamson Department of Computer Science University of Calgary Winter 2018

WiFi Networks: IEEE b Wireless LANs. Carey Williamson Department of Computer Science University of Calgary Winter 2018 WiFi Networks: IEEE 802.11b Wireless LANs Carey Williamson Department of Computer Science University of Calgary Winter 2018 Background (1 of 2) In many respects, the IEEE 802.11b wireless LAN (WLAN) standard

More information

Lecture 16: QoS and "

Lecture 16: QoS and Lecture 16: QoS and 802.11" CSE 123: Computer Networks Alex C. Snoeren HW 4 due now! Lecture 16 Overview" Network-wide QoS IntServ DifServ 802.11 Wireless CSMA/CA Hidden Terminals RTS/CTS CSE 123 Lecture

More information

Data Communications. Data Link Layer Protocols Wireless LANs

Data Communications. Data Link Layer Protocols Wireless LANs Data Communications Data Link Layer Protocols Wireless LANs Wireless Networks Several different types of communications networks are using unguided media. These networks are generally referred to as wireless

More information

Computer Networks. Wireless LANs

Computer Networks. Wireless LANs Computer Networks Wireless LANs Mobile Communication Technology according to IEEE (examples) Local wireless networks WLAN 802.11 Personal wireless nw WPAN 802.15 WiFi 802.11a 802.11b 802.11h 802.11i/e/

More information

Local Area Networks NETW 901

Local Area Networks NETW 901 Local Area Networks NETW 901 Lecture 4 Wireless LAN Course Instructor: Dr.-Ing. Maggie Mashaly maggie.ezzat@guc.edu.eg C3.220 1 Contents What is a Wireless LAN? Applications and Requirements Transmission

More information

Mobile & Wireless Networking. Lecture 7: Wireless LAN

Mobile & Wireless Networking. Lecture 7: Wireless LAN 192620010 Mobile & Wireless Networking Lecture 7: Wireless LAN [Schiller, Section 7.3] [Reader, Part 6] [Optional: "IEEE 802.11n Development: History, Process, and Technology", Perahia, IEEE Communications

More information

ICE 1332/0715 Mobile Computing (Summer, 2008)

ICE 1332/0715 Mobile Computing (Summer, 2008) ICE 1332/0715 Mobile Computing (Summer, 2008) IEEE 802.11 Prof. Chansu Yu http://academic.csuohio.edu/yuc/ Contents Overview of IEEE 802.11 Frame formats MAC frame PHY frame IEEE 802.11 IEEE 802.11b IEEE

More information

Chapter 6 Medium Access Control Protocols and Local Area Networks

Chapter 6 Medium Access Control Protocols and Local Area Networks Chapter 6 Medium Access Control Protocols and Local Area Networks 802.11 Wireless LAN CSE 3213, Winter 2010 Instructor: Foroohar Foroozan Wireless Data Communications Wireless communications compelling

More information

04/11/2011. Wireless LANs. CSE 3213 Fall November Overview

04/11/2011. Wireless LANs. CSE 3213 Fall November Overview Wireless LANs CSE 3213 Fall 2011 4 November 2011 Overview 2 1 Infrastructure Wireless LAN 3 Applications of Wireless LANs Key application areas: LAN extension cross-building interconnect nomadic access

More information

Advanced Computer Networks WLAN

Advanced Computer Networks WLAN Advanced Computer Networks 263 3501 00 WLAN Patrick Stuedi Spring Semester 2014 1 Oriana Riva, Department of Computer Science ETH Zürich Last week Outlook Medium Access COPE Short Range Wireless Networks:

More information

Institute of Electrical and Electronics Engineers (IEEE) IEEE standards

Institute of Electrical and Electronics Engineers (IEEE) IEEE standards HW Institute of Electrical and Electronics Engineers (IEEE) IEEE 802.11 standards WLAN Standard (IEEE 802.11) The IEEE 802.11 is a family of standards that governs the operations and functions of WLANs.

More information

Architecture. Copyright :I1996 IEEE. All rights reserved. This contains parts from an unapproved draft, subject to change

Architecture. Copyright :I1996 IEEE. All rights reserved. This contains parts from an unapproved draft, subject to change 802.11 Architecture Copyright :I1996 IEEE. All rights reserved. This contains parts from an unapproved draft, subject to change What is unique about wireless? Difficult media - interference and noise -

More information

3.1. Introduction to WLAN IEEE

3.1. Introduction to WLAN IEEE 3.1. Introduction to WLAN IEEE 802.11 WCOM, WLAN, 1 References [1] J. Schiller, Mobile Communications, 2nd Ed., Pearson, 2003. [2] Martin Sauter, "From GSM to LTE", chapter 6, Wiley, 2011. [3] wiki to

More information

CSMC 417. Computer Networks Prof. Ashok K Agrawala Ashok Agrawala. Fall 2018 CMSC417 Set 1 1

CSMC 417. Computer Networks Prof. Ashok K Agrawala Ashok Agrawala. Fall 2018 CMSC417 Set 1 1 CSMC 417 Computer Networks Prof. Ashok K Agrawala 2018 Ashok Agrawala Fall 2018 CMSC417 Set 1 1 The Medium Access Control Sublayer November 18 Nov 6, 2018 2 Wireless Networking Technologies November 18

More information

Wireless Communication Session 4 Wi-Fi IEEE standard

Wireless Communication Session 4 Wi-Fi IEEE standard Wireless Communication Session 4 Wi-Fi IEEE802.11 standard M. Daneshvar Farzanegan Soourosh.blogfa.com smdanesh@yahoo.com 1 Reminder on frequencies and wavelenghts twisted pair coax cable optical transmission

More information

MAC in /20/06

MAC in /20/06 MAC in 802.11 2/20/06 MAC Multiple users share common medium. Important issues: Collision detection Delay Fairness Hidden terminals Synchronization Power management Roaming Use 802.11 as an example to

More information

MSIT 413: Wireless Technologies Week 8

MSIT 413: Wireless Technologies Week 8 MSIT 413: Wireless Technologies Week 8 Michael L. Honig Department of EECS Northwestern University November 2017 The Multiple Access Problem How can multiple mobiles access (communicate with) the same

More information

Wireless Local Area Network (IEEE )

Wireless Local Area Network (IEEE ) Wireless Local Area Network (IEEE 802.11) -IEEE 802.11 Specifies a single Medium Access Control (MAC) sublayer and 3 Physical Layer Specifications. Stations can operate in two configurations : Ad-hoc mode

More information

Wireless LANs. Outline. Outline II. Benefits Applications Technologies Issues Configurations Overview of Standard

Wireless LANs. Outline. Outline II. Benefits Applications Technologies Issues Configurations Overview of Standard Wireless LANs Outline Benefits Applications Technologies Issues Configurations Overview of 802.11 Standard Dr. Michael S. Boykin Spring 02-2 Local Area Networks 2 Outline II MAC layer protocols PHY layer

More information

IEEE Wireless LANs

IEEE Wireless LANs Unit 11 IEEE 802.11 Wireless LANs Shyam Parekh IEEE 802.11 Wireless LANs References Standards Basics Physical Layer 802.11b 802.11a MAC Framing Details Management PCF QoS (802.11e) Security Take Away Points

More information

Wireless# Guide to Wireless Communications. Objectives

Wireless# Guide to Wireless Communications. Objectives Wireless# Guide to Wireless Communications Chapter 8 High-Speed WLANs and WLAN Security Objectives Describe how IEEE 802.11a networks function and how they differ from 802.11 networks Outline how 802.11g

More information

Wireless Local Area Networks (WLANs) Part I

Wireless Local Area Networks (WLANs) Part I Wireless Local Area Networks (WLANs) Part I Raj Jain Professor of CSE Washington University in Saint Louis Saint Louis, MO 63130 Jain@cse.wustl.edu These slides are available on-line at: http://www.cse.wustl.edu/~jain/cse574-08/

More information

Chapter 6 Wireless and Mobile Networks. Csci 4211 David H.C. Du

Chapter 6 Wireless and Mobile Networks. Csci 4211 David H.C. Du Chapter 6 Wireless and Mobile Networks Csci 4211 David H.C. Du Wireless LAN IEEE 802.11 a, b, g IEEE 802.15 Buletooth Hidden Terminal Effect Hidden Terminal Problem Hidden terminals A, C cannot hear each

More information

IEEE WLANs (WiFi) Part II/III System Overview and MAC Layer

IEEE WLANs (WiFi) Part II/III System Overview and MAC Layer IEEE 802.11 WLANs (WiFi) Part II/III System Overview and MAC Layer Design goals for wireless LANs (WLANs) Global, seamless operation Low power for battery use No special permissions or licenses needed

More information

Computer Communication III

Computer Communication III Computer Communication III Wireless Media Access IEEE 802.11 Wireless LAN Advantages of Wireless LANs Using the license free ISM band at 2.4 GHz no complicated or expensive licenses necessary very cost

More information

Data and Computer Communications. Chapter 13 Wireless LANs

Data and Computer Communications. Chapter 13 Wireless LANs Data and Computer Communications Chapter 13 Wireless LANs Wireless LAN Topology Infrastructure LAN Connect to stations on wired LAN and in other cells May do automatic handoff Ad hoc LAN No hub Peer-to-peer

More information

Introduction to IEEE

Introduction to IEEE Introduction to IEEE 802.11 Characteristics of wireless LANs Advantages very flexible within the reception area Ad hoc networks without previous planning possible (almost) no wiring difficulties more robust

More information

Investigation of WLAN

Investigation of WLAN Investigation of WLAN Table of Contents Table of Contents...1 ABBREVIATIONS...II 1 Introduction...3 2 IEEE 802.11...3 2.1 Architecture...3 2.2 MAC layer...4 2.3 PHY layer...9 2.4 Mobility in IEEE 802.11...12

More information

Author: Bill Buchanan. Wireless LAN. Unit 2: Wireless Fundamentals

Author: Bill Buchanan. Wireless LAN. Unit 2: Wireless Fundamentals Wireless LAN Unit 2: Wireless Fundamentals Wireless connections which technology? Areas covered: Basic radio parameters. This area covers the main type of wireless communications. IEEE 802.11b issues.

More information

standard. Acknowledgement: Slides borrowed from Richard Y. Yale

standard. Acknowledgement: Slides borrowed from Richard Y. Yale 802.11 standard Acknowledgement: Slides borrowed from Richard Y. Yang @ Yale IEEE 802.11 Requirements Design for small coverage (e.g. office, home) Low/no mobility High data rate applications Ability to

More information

Lesson 2-3: The IEEE x MAC Layer

Lesson 2-3: The IEEE x MAC Layer Module 2: Establishing Wireless Connectivity Lesson 2-3: The IEEE 802.11x MAC Layer Lesson Overview This lesson describes basic IEEE 802.11x MAC operation, beginning with an explanation of contention schemes

More information

Topics for Today. More on Ethernet. Wireless LANs Readings. Topology and Wiring Switched Ethernet Fast Ethernet Gigabit Ethernet. 4.3 to 4.

Topics for Today. More on Ethernet. Wireless LANs Readings. Topology and Wiring Switched Ethernet Fast Ethernet Gigabit Ethernet. 4.3 to 4. Topics for Today More on Ethernet Topology and Wiring Switched Ethernet Fast Ethernet Gigabit Ethernet Wireless LANs Readings 4.3 to 4.4 1 Original Ethernet Wiring Heavy coaxial cable, called thicknet,

More information

Mobile Communications Chapter 7: Wireless LANs

Mobile Communications Chapter 7: Wireless LANs Mobile Communications Chapter 7: Wireless LANs Characteristics IEEE 802.11 (PHY, MAC, Roaming,.11a, b, g, h, i, n z) Bluetooth / IEEE 802.15.x IEEE 802.16/.20/.21/.22 RFID Comparison Prof. Jó Ueyama courtesy

More information

Wireless Local Area Networks. Networks: Wireless LANs 1

Wireless Local Area Networks. Networks: Wireless LANs 1 Wireless Local Area Networks Networks: Wireless LANs 1 Wireless Local Area Networks The proliferation of laptop computers and other mobile devices (PDAs and cell phones) created an obvious application

More information

Overview : Computer Networking. Spectrum Use Comments. Spectrum Allocation in US Link layer challenges and WiFi WiFi

Overview : Computer Networking. Spectrum Use Comments. Spectrum Allocation in US Link layer challenges and WiFi WiFi Overview 15-441 15-441: Computer Networking 15-641 Lecture 21: Wireless Justine Sherry Peter Steenkiste Fall 2017 www.cs.cmu.edu/~prs/15-441-f17 Link layer challenges and WiFi WiFi Basic WiFi design Some

More information

4.3 IEEE Physical Layer IEEE IEEE b IEEE a IEEE g IEEE n IEEE 802.

4.3 IEEE Physical Layer IEEE IEEE b IEEE a IEEE g IEEE n IEEE 802. 4.3 IEEE 802.11 Physical Layer 4.3.1 IEEE 802.11 4.3.2 IEEE 802.11b 4.3.3 IEEE 802.11a 4.3.4 IEEE 802.11g 4.3.5 IEEE 802.11n 4.3.6 IEEE 802.11ac,ad Andreas Könsgen Summer Term 2012 4.3.3 IEEE 802.11a Data

More information

Optional Point Coordination Function (PCF)

Optional Point Coordination Function (PCF) Optional Point Coordination Function (PCF) Time Bounded / Async Contention Free Service PCF Optional DCF (CSMA/CA ) Async Contention Service MAC PHY Contention Free Service uses Point Coordination Function

More information

I N D E X Numerics 100 Mbps WLANs, WLANs, 88

I N D E X Numerics 100 Mbps WLANs, WLANs, 88 I N D E X Numerics 100 Mbps WLANs, 233 234 802.11 WLANs, 88 control frames, 54 ACK frames, 57 CF-End frames, 57 58 CTS frames, 56 PS-Poll frames, 54 55 RTS frames, 55 56 DSSS, 93-95 data frames, 76-78

More information

Chapter 7: Wireless LANs

Chapter 7: Wireless LANs Mobile Communications Chapter 7: Wireless LANs Characteristics IEEE 802.11 (PHY, MAC, Roaming,.11a, b, g, h, i, n z) Bluetooth / IEEE 802.15.x IEEE 802.16/.20/.21/.22 RFID Comparison Prof. Jó Ueyama courtesy

More information

WNC-0300USB. 11g Wireless USB Adapter USER MANUAL

WNC-0300USB. 11g Wireless USB Adapter USER MANUAL WNC-0300USB 11g Wireless USB Adapter USER MANUAL Contents 1. Introduction...3 1.1 Product Feature...3 1.2 System Requirement...3 2. Getting Start...3 2.1 LED Indicators...3 2.2 Install the 54Mbps Wireless

More information

IEEE MAC Sublayer (Based on IEEE )

IEEE MAC Sublayer (Based on IEEE ) IEEE 802.11 MAC Sublayer (Based on IEEE 802.11-1999) Wireless Networking Sunghyun Choi, Associate Professor Multimedia & Wireless Networking Lab. (MWNL) School of Electrical Engineering Seoul National

More information

Multiple Access Links and Protocols

Multiple Access Links and Protocols Multiple Access Links and Protocols Two types of links : point-to-point PPP for dial-up access point-to-point link between Ethernet switch and host broadcast (shared wire or medium) old-fashioned Ethernet

More information

IEEE Technical Tutorial. Introduction. IEEE Architecture

IEEE Technical Tutorial. Introduction. IEEE Architecture IEEE 802.11 Technical Tutorial Introduction The purpose of this document is to give technical readers a basic overview of the new 802.11 Standard, enabling them to understand the basic concepts, principle

More information

Chapter 7: Wireless LANs

Chapter 7: Wireless LANs Mobile Communications Chapter 7: Wireless LANs Characteristics IEEE 802.11 (PHY, MAC, Roaming,.11a, b, g, h, i, n z) Bluetooth / IEEE 802.15.x IEEE 802.16/.20/.21/.22 RFID Comparison Prof. Jó Ueyama courtesy

More information

Page 1. Wireless LANs: Design Requirements. Evolution. EEC173B/ECS152C, Winter Wireless LANs

Page 1. Wireless LANs: Design Requirements. Evolution. EEC173B/ECS152C, Winter Wireless LANs EEC173B/ECS152C, Winter 2006 Wireless LANs Evolution of Technology & Standards IEEE 802.11 Design Choices Architecture & Protocols PHY layer MAC layer design Acknowledgment: Selected slides from Prof.

More information

original standard a transmission at 5 GHz bit rate 54 Mbit/s b support for 5.5 and 11 Mbit/s e QoS

original standard a transmission at 5 GHz bit rate 54 Mbit/s b support for 5.5 and 11 Mbit/s e QoS IEEE 802.11 The standard defines a wireless physical interface and the MAC layer while LLC layer is defined in 802.2. The standardization process, started in 1990, is still going on; some versions are:

More information

Wireless technology Principles of Security

Wireless technology Principles of Security Wireless technology Principles of Security 1 Wireless technologies 2 Overview This module provides an introduction to the rapidly evolving technology of wireless LANs (WLANs). WLANs redefine the way the

More information

Wireless Local Area Networks (WLANs)) and Wireless Sensor Networks (WSNs) Computer Networks: Wireless Networks 1

Wireless Local Area Networks (WLANs)) and Wireless Sensor Networks (WSNs) Computer Networks: Wireless Networks 1 Wireless Local Area Networks (WLANs)) and Wireless Sensor Networks (WSNs) Computer Networks: Wireless Networks 1 Wireless Local Area Networks The proliferation of laptop computers and other mobile devices

More information

Delivering Voice over IEEE WLAN Networks

Delivering Voice over IEEE WLAN Networks Delivering Voice over IEEE 802.11 WLAN Networks Al Petrick, Jim Zyren, Juan Figueroa Harris Semiconductor Palm Bay Florida Abstract The IEEE 802.11 wireless LAN standard was developed primarily for packet

More information

CHAPTER 8: LAN Standards

CHAPTER 8: LAN Standards CHAPTER 8: LAN Standards DR. BHARGAVI GOSWAMI, ASSOCIATE PROFESSOR HEAD, DEPARTMENT OF COMPUTER SCIENCE, GARDEN CITY COLLEGE BANGALORE. LAN STRUCTURE NETWORK INTERFACE CARD MEDIUM ACCESS CONTROL SUB LAYER

More information

Mobile Communications Chapter 7: Wireless LANs

Mobile Communications Chapter 7: Wireless LANs Characteristics IEEE 802.11 PHY MAC Roaming IEEE 802.11a, b, g, e HIPERLAN Bluetooth Comparisons Prof. Dr.-Ing. Jochen Schiller, http://www.jochenschiller.de/ MC SS02 7.1 Comparison: infrastructure vs.

More information

Introduction to Wireless Networking CS 490WN/ECE 401WN Winter Lecture 4: Wireless LANs and IEEE Part II

Introduction to Wireless Networking CS 490WN/ECE 401WN Winter Lecture 4: Wireless LANs and IEEE Part II Introduction to Wireless Networking CS 490WN/ECE 401WN Winter 2007 Lecture 4: Wireless LANs and IEEE 802.11 Part II This lecture continues the study of wireless LANs by looking at IEEE 802.11. I. 802.11

More information

Actual4Test. Actual4test - actual test exam dumps-pass for IT exams

Actual4Test.  Actual4test - actual test exam dumps-pass for IT exams Actual4Test http://www.actual4test.com Actual4test - actual test exam dumps-pass for IT exams Exam : PW0-205 Title : Certified wireless analusis professional(cwap) Vendors : CWNP Version : DEMO Get Latest

More information

Hands-On Exercises: IEEE Standard

Hands-On Exercises: IEEE Standard Hands-On Exercises: IEEE 802.11 Standard Mohammad Hossein Manshaei and Jean-Pierre Hubaux {hossein.manshaei,jean-pierre.hubaux}@epfl.ch Laboratory for Computer Communications and Applications (LCA) March

More information

Mobile Communications Chapter 7: Wireless LANs

Mobile Communications Chapter 7: Wireless LANs Mobile Communications Chapter 7: Wireless LANs Characteristics IEEE 802.11 PHY MAC Roaming IEEE 802.11a, b, g, e HIPERLAN Bluetooth Comparisons Prof. Dr.-Ing. Jochen Schiller, http://www.jochenschiller.de/

More information

MAC. Fall Data Communications II 1

MAC. Fall Data Communications II 1 802.11 MAC Fall 2005 91.564 Data Communications II 1 RF Quality (ACK) Fall 2005 91.564 Data Communications II 2 Hidden Terminal (RTS/CTS) Fall 2005 91.564 Data Communications II 3 MAC Coordination Functions

More information

Functions of physical layer:

Functions of physical layer: Chapter 14 Functions of physical layer: Encoding/decoding of signals Preamble generation/removal (for synchronization) Bit transmission/reception Includes specification of the transmission medium Functions

More information

Local Area Networks. Lecture 17 Fall Token Ring and FDDI

Local Area Networks. Lecture 17 Fall Token Ring and FDDI Local Area Networks Lecture 17 Fall 2010 Token Ring and FDDI IEEE 802.5 Ring LAN Unidirectional ring network 4 Mbps and 16 Mbps on twisted pair Differential Manchester line coding Token passing protocol

More information

Overview of Wireless LANs

Overview of Wireless LANs Wireless LANs Chapter 17 CS420/520 Axel Krings Page 1 Overview of Wireless LANs use wireless transmission medium issues of high prices, low data rates, occupational safety concerns, & licensing requirements

More information

Wireless Networks. CSE 3461: Introduction to Computer Networking Reading: , Kurose and Ross

Wireless Networks. CSE 3461: Introduction to Computer Networking Reading: , Kurose and Ross Wireless Networks CSE 3461: Introduction to Computer Networking Reading: 6.1 6.3, Kurose and Ross 1 Wireless Networks Background: Number of wireless (mobile) phone subscribers now exceeds number of wired

More information

Wireless Local Area Part 2

Wireless Local Area Part 2 Wireless Local Area Part 2 BER 802.11: advanced capabilities Rate Adaptation base station, mobile dynamically change transmission rate (physical layer modulation technique) as mobile moves, SNR varies

More information

WLAN 1 IEEE Basic Connectivity. Manuel Ricardo. Faculdade de Engenharia da Universidade do Porto

WLAN 1 IEEE Basic Connectivity. Manuel Ricardo. Faculdade de Engenharia da Universidade do Porto WLAN 1 IEEE 802.11 Basic Connectivity Manuel Ricardo Faculdade de Engenharia da Universidade do Porto WLAN 2 Acknowledgements Based on Jochen Schiller slides Supporting text» Jochen Schiller, Mobile Comunications,

More information

Mobile Communications Chapter 7: Wireless LANs

Mobile Communications Chapter 7: Wireless LANs Characteristics IEEE 802.11 PHY MAC Roaming IEEE 802.11a, b, g, e HIPERLAN Bluetooth Comparisons Prof. Dr.-Ing. Jochen Schiller, http://www.jochenschiller.de/ MC SS02 7.1 Characteristics of Wireless LANs

More information

Wireless Data Networking IEEE & Overview of IEEE b

Wireless Data Networking IEEE & Overview of IEEE b Wireless Data Networking IEEE 802.11 & Overview of IEEE 802.11b Dr. Arian Durresi The Ohio State University Columbus, OH 43210 durresi@cis.ohio-state.edu 1 Overview Wireless Application Market Wireless

More information

Wireless LAN Access Point

Wireless LAN Access Point Wireless LAN Access Point IEEE 802.11b 11Mbps User s Manual Table of Contents Chapter 1 Introduction... 1 1.1 Package Contents... 2 1.2 Features... 2 1.3 Specifications... 2 1.4 Physical Description...

More information

Wireless and WiFi. Daniel Zappala. CS 460 Computer Networking Brigham Young University

Wireless and WiFi. Daniel Zappala. CS 460 Computer Networking Brigham Young University Wireless and WiFi Daniel Zappala CS 460 Computer Networking Brigham Young University Wireless Networks 2/28 mobile phone subscribers now outnumber wired phone subscribers similar trend likely with Internet

More information

IT220 Network Standards & Protocols. Unit 6: Chapter 6 Wireless LANs

IT220 Network Standards & Protocols. Unit 6: Chapter 6 Wireless LANs IT220 Network Standards & Protocols Unit 6: Chapter 6 Wireless LANs 2 Objectives Identify the major needs and stakeholders for computer networks and network applications. Identify the classifications of

More information

Lecture 23 Overview. Last Lecture. This Lecture. Next Lecture ADSL, ATM. Wireless Technologies (1) Source: chapters 6.2, 15

Lecture 23 Overview. Last Lecture. This Lecture. Next Lecture ADSL, ATM. Wireless Technologies (1) Source: chapters 6.2, 15 Lecture 23 Overview Last Lecture ADSL, ATM This Lecture Wireless Technologies (1) Wireless LAN, CSMA/CA, Bluetooth Source: chapters 6.2, 15 Next Lecture Wireless Technologies (2) Source: chapter 16, 19.3

More information

Introduction. Giuseppe Bianchi, Ilenia Tinnirello

Introduction. Giuseppe Bianchi, Ilenia Tinnirello IEEE 802.11 Wireless LANs Introduction WLAN History Ł Original goal: Deploy wireless Ethernet First generation proprietary solutions (end 80, begin 90) WaveLAN (AT&T)) HomeRF (Proxim) Abandoned by major

More information

Chapter 7. Basic Wireless Concepts and Configuration. Part I

Chapter 7. Basic Wireless Concepts and Configuration. Part I Chapter 7 Basic Wireless Concepts and Configuration Part I CCNA3-1 Chapter 7-1 Note for Instructors These presentations are the result of a collaboration among the instructors at St. Clair College in Windsor,

More information

Chapter 10: Wireless LAN & VLANs

Chapter 10: Wireless LAN & VLANs Chapter 10: Wireless LAN & VLANs Abdullah Konak School of Information Sciences and Technology Penn State Berks Wireless Transmission for LAN Radio Frequency Transmission (RF) Infrared Transmission 2 1

More information

Lecture (08) Wireless Traffic Flow and AP Discovery

Lecture (08) Wireless Traffic Flow and AP Discovery Lecture (08) Wireless Traffic Flow and AP Discovery Dr. Ahmed ElShafee 1 Dr. Ahmed ElShafee, ACU Spring 2011, Wireless Network Agenda Wireless Frame Types Sending a Frames Wireless Frame Headers Frame

More information

NT1210 Introduction to Networking. Unit 6: Chapter 6, Wireless LANs

NT1210 Introduction to Networking. Unit 6: Chapter 6, Wireless LANs NT1210 Introduction to Networking Unit 6: Chapter 6, Wireless LANs Objectives Identify the major needs and stakeholders for computer networks and network applications. Identify the classifications of networks

More information

Wireless Networking based on Chapter 15 of CompTIA Network+ Exam Guide, 4th ed., Mike Meyers

Wireless Networking based on Chapter 15 of CompTIA Network+ Exam Guide, 4th ed., Mike Meyers Wireless Networking 802.11 based on Chapter 15 of CompTIA Network+ Exam Guide, 4th ed., Mike Meyers topics Standards Technical Concepts Implementation Troubleshooting 802.11 timeline source: Anandtech

More information

CS698T Wireless Networks: Principles and Practice

CS698T Wireless Networks: Principles and Practice CS698T Wireless Networks: Principles and Practice IEEE 802.11 (WLAN/WiFi) Bhaskaran Raman, Department of CSE, IIT Kanpur http://www.cse.iitk.ac.in/users/braman/courses/wless-spring2007/ IEEE 802.11 (WiFi)

More information

WLAN 1 IEEE Manuel Ricardo. Faculdade de Engenharia da Universidade do Porto

WLAN 1 IEEE Manuel Ricardo. Faculdade de Engenharia da Universidade do Porto WLAN 1 IEEE 802.11 Basic Connectivity Manuel Ricardo Faculdade de Engenharia da Universidade do Porto WLAN 2 Acknowledgements Based on Jochen Schiller slides Supporting text» Jochen Schiller, Mobile Comunications,

More information

Wireless Local Area Networks (WLANs) and Wireless Sensor Networks (WSNs) Primer. Computer Networks: Wireless LANs

Wireless Local Area Networks (WLANs) and Wireless Sensor Networks (WSNs) Primer. Computer Networks: Wireless LANs Wireless Local Area Networks (WLANs) and Wireless Sensor Networks (WSNs) Primer 1 Wireless Local Area Networks (WLANs) The proliferation of laptop computers and other mobile devices (PDAs and cell phones)

More information

Overview. Wireless networks basics IEEE (Wi-Fi) a/b/g/n ad Hoc MAC protocols ad Hoc routing DSR AODV

Overview. Wireless networks basics IEEE (Wi-Fi) a/b/g/n ad Hoc MAC protocols ad Hoc routing DSR AODV Wireless networks 1 Overview Wireless networks basics IEEE 802.11 (Wi-Fi) a/b/g/n ad Hoc MAC protocols ad Hoc routing DSR AODV 2 Wireless Networks Autonomous systems of mobile hosts connected by wireless

More information

WIRELESS LANS. By: M. Habibullah Pagarkar Mandar Gori Rajesh Jaiswal

WIRELESS LANS. By: M. Habibullah Pagarkar Mandar Gori Rajesh Jaiswal WIRELESS LANS By: M. Habibullah Pagarkar Mandar Gori Rajesh Jaiswal Introduction Why wireless? World will become fully mobile Increase in wireless devices usage Wireless will succeed; integrates into many

More information

Wireless Networked Systems

Wireless Networked Systems Wireless Networked Systems CS 795/895 - Spring 2013 Lec #6: Medium Access Control QoS and Service Differentiation, and Power Management Tamer Nadeem Dept. of Computer Science Quality of Service (802.11e)

More information

Page 1. Outline : Wireless Networks Lecture 11: MAC. Standardization of Wireless Networks. History. Frequency Bands

Page 1. Outline : Wireless Networks Lecture 11: MAC. Standardization of Wireless Networks. History. Frequency Bands Outline 18-759 : Wireless s Lecture 11: 80.11 Peter Steenkiste Dina Papagiannaki Spring Semester 009 http://www.cs.cmu.edu/~prs/wireless09/ Peter A. Steenkiste, CMU 1 80 protocol overview Wireless LANs

More information

CSNT 180 Wireless Networking. Chapter 7 WLAN Terminology and Technology

CSNT 180 Wireless Networking. Chapter 7 WLAN Terminology and Technology CSNT 180 Wireless Networking Chapter 7 WLAN Terminology and Technology Norman McEntire norman.mcentire@servin.com Founder, Servin Corporation, http://servin.com Technology Training for Technology Professionals

More information

Internet Protocol Stack

Internet Protocol Stack Internet Protocol Stack Application: supporting network applications FTP, SMTP, HTTP Transport: data transfer between processes TCP, UDP Network: routing of datagrams from source to destination IP, routing

More information

CSC344 Wireless and Mobile Computing. Department of Computer Science COMSATS Institute of Information Technology

CSC344 Wireless and Mobile Computing. Department of Computer Science COMSATS Institute of Information Technology CSC344 Wireless and Mobile Computing Department of Computer Science COMSATS Institute of Information Technology Wireless Local Area Networks (WLANs) Part I Almost all wireless LANs now are IEEE 802.11

More information

Wireless Communications

Wireless Communications 4. Medium Access Control Sublayer DIN/CTC/UEM 2018 Why do we need MAC for? Medium Access Control (MAC) Shared medium instead of point-to-point link MAC sublayer controls access to shared medium Examples:

More information

Introduction to Wireless LAN

Introduction to Wireless LAN Introduction to Wireless LAN Po-Ning Chen, Professor Depart. Of Communications Engineering National Chiao-Tung University 1 Topologies of Wireless o Infrastructure versus ad hoc Infrastructure Portable-to-fixed

More information

Wireless and Mobile Networks

Wireless and Mobile Networks Wireless and Mobile Networks Raj Jain Washington University in Saint Louis Saint Louis, MO 63130 Jain@wustl.edu Audio/Video recordings of this lecture are available on-line at: http://www.cse.wustl.edu/~jain/cse473-11/

More information

Unit 7 Media Access Control (MAC)

Unit 7 Media Access Control (MAC) Unit 7 Media Access Control (MAC) 1 Internet Model 2 Sublayers of Data Link Layer Logical link control (LLC) Flow control Error control Media access control (MAC) access control 3 Categorization of MAC

More information

Data and Computer Communications

Data and Computer Communications Data and Computer Communications Chapter 17 Wireless LANs Eighth Edition by William Stallings Overview of Wireless LANs use wireless transmission medium Wireless LAN were little used issues of high prices,

More information

Wireless Local Area Network. Internet Protocol Suite

Wireless Local Area Network. Internet Protocol Suite Wireless Local Area Network Internet Protocol Suite Application layer File transfer protocol Telnet Hypertext transfer protocol Transport layer Network layer Host-tonetwork layer User datagram protocol

More information

CMPE 257: Wireless and Mobile Networking

CMPE 257: Wireless and Mobile Networking CMPE 257: Wireless and Mobile Networking Katia Obraczka Computer Engineering UCSC Baskin Engineering Lecture 3 CMPE 257 Spring'15 1 Next week Announcements April 14: ICN (Spencer Sevilla) April 16: DTN

More information

Outline. CS5984 Mobile Computing. IEEE 802 Architecture 1/7. IEEE 802 Architecture 2/7. IEEE 802 Architecture 3/7. Dr. Ayman Abdel-Hamid, CS5984

Outline. CS5984 Mobile Computing. IEEE 802 Architecture 1/7. IEEE 802 Architecture 2/7. IEEE 802 Architecture 3/7. Dr. Ayman Abdel-Hamid, CS5984 CS5984 Mobile Computing Dr. Ayman Abdel-Hamid Computer Science Department Virginia Tech Outline IEEE 82 Architecture IEEE 82. Wireless LANs Based on Chapter 4 in Wireless Communications and Networks, William

More information

CMPE 257: Wireless and Mobile Networking

CMPE 257: Wireless and Mobile Networking CMPE 257: Wireless and Mobile Networking Katia Obraczka Computer Engineering UCSC Baskin Engineering Lecture 3 CMPE 257 Winter'11 1 Announcements Accessing secure part of the class Web page: User id: cmpe257.

More information

Mohamed Khedr.

Mohamed Khedr. Mohamed Khedr http://webmail.aast.edu/~khedr Tentatively Week 1 Week 2 Week 3 Week 4 Week 5 Week 6 Week 7 Week 8 Week 9 Week 10 Week 11 Week 12 Week 13 Week 14 Week 15 Overview Packet Switching IP addressing

More information

WiFi Overview. 2/14/2005 Pietrosemoli 1

WiFi Overview. 2/14/2005 Pietrosemoli 1 WiFi Overview Abdus Salam ICTP, February 2005 Radio Based Computer Networking for Research and Training in Developing Countries Ermanno Pietrosemoli Latin American Networking School (Fundación EsLaRed)

More information

ECE442 Communications Lecture 3. Wireless Local Area Networks

ECE442 Communications Lecture 3. Wireless Local Area Networks ECE442 Communications Lecture 3. Wireless Local Area Networks Husheng Li Dept. of Electrical Engineering and Computer Science Spring, 2014 Wireless Local Networks 1 A WLAN links two or more devices using

More information