Introduction to Wireless Networking Module-01 Overview of Wireless Standards, Organizations and Technology Jerry Bernardini Community College of Rhode Island 7/13/20151Wireless Networking J. Bernardini

Presentation Reference Material CWNA Certified Wireless Network Administration Official Study Guide (PWO-104), David Coleman, David Westcott, 2009, Chapter-1 Wireless Networking in the Developing World 7/13/2015Wireless Networking J. Bernardini2

Abbreviated Wireless Network History ??dates 1830: Professor Joseph Henry transmitted the first practical electrical signal. 1880: Maxwell’s Equations 1905: Marconi 1920: Radio Receivers 1935: Television 1941: Radar 1958: Satellite 1970: ALOHAnet 1990: Internet 1998: WLAN 7/13/2015Wireless Networking J. Bernardini3

Why Study Wireless Networks? A Partial List Cordless phones Wireless Voice over IP phones Wireless print servers Wireless access points, routers, and bridges Radio Frequency Identification devices Wireless presentation gateways Wireless conferencing systems Laptop computers, PDAs, and other mobile wireless client device 7/13/2015Wireless Networking J. Bernardini4

Wireless Industry Guided by Three Categories of Organizations Regulation- Boundaries of Operation – Federal Communications Commission (FCC) – European Telecommunications Standards Institute (ETSI) Power limits and Frequencies Standardization- How systems work together – Institute of Electrical and Electronics Engineers (IEEE) a, b, g, n Compatibility – Tests for interoperability – Wi-Fi Alliance If you buy Wi-Fi certified gear it work with other Wi-Fi gear 7/13/2015Wireless Networking J. Bernardini5

FCC - Federal Communications Commission Regulatory Bodies – City, State, Country FCC- Born in 1934 to regulate radio, television, cable, satellite and wire communications FCC regulates – Radio frequencies – Output power levels – Indoor and Outdoor usage Every country has regulatory bodies 7/13/2015Wireless Networking J. Bernardini6

FCC Wireless Bands 1985:Industry, Scientific and Medical Industrial License-Free Bands – ISM Bands – 900 MHz band, (900 to 928 MHz range) – 2.4 GHz band, (2.4 to GHz range) – 5 GHz band, (5.725 to GHz range) 1997: Unlicensed National Information Infrastructure U-NII bands – 5.15 to 5.25 GHz – 5.25 to 5.35 GHz – to GHz 7/13/2015Wireless Networking J. Bernardini7

FCC Unlicensed Bands AdvantagesDisadvantages No licenses required No Fees No Permits Comply with rules and build anything Everyone can use the bands Interference between users Bandwidth Contention First-come-first –serve Interference from late- comers 7/13/2015Wireless Networking J. Bernardini8

FCC Regulates Frequencies Frequencies are grouped into bands – Wireless LAN bands include: (Hz = Hertz) 7/13/2015Wireless Networking J. Bernardini9 Frequency BandTotal BandwidthLicense-Free Band 2400–2500 MHz100 MHzISM 5.15–5.25 GHz100 MHzU-NII 5.25–5.35 GHz100 MHzU-NII 5.470–5.725 GHz255 MHzU-NII 5.725–5.825 GHz100 MHzU-NII

FCC Power Output Limits-U-NI Bands 7/13/2015Wireless Networking J. Bernardini10 BandPower OutputLimits Area Usage U-NII 5.15–5.25 GHz40 mWRestricted to indoor operations U-NII 5.25–5.35 GHz200 mWIndoor/outdoor U-NII 5.470–5.725 GHz200 mWIndoor/outdoor U-NII 5.725–5.825 GHz800 mWHigher output power assumes outdoor operations mw = 1/1000 watt

Non-USA Standard Organizations OfCom-Office of Communication –United Kingdom MIC- Ministry of Internal Affairs and Communications-Japan ARIB-Association of Radio and Businesses – Japan ACMA-Australian Communications and Media Authority 7/13/2015Wireless Networking J. Bernardini11

International Telecommunications Union Radiocommunications Sector (ITU-R) 1947: United Nations creates ITU-R to: – Promote cooperation and technical development ITU-R maintains a database of frequencies with five administrative regions – Region A: The Americas – Region B: Western Europe – Region C: Eastern Europe – Region D: Africa – Region E: Asia and Australia 7/13/2015Wireless Networking J. Bernardini12

Institute of Electrical and Electronics Engineers - IEEE (Eye-triple-E) World’s leading non-profit professional organization for the advancement of technology Mission – – promote “the engineering process of creating, developing, integrating, sharing, and applying knowledge about electronics and information technologies and sciences for the benefit of humanity and the profession.” 350,000 individual members in 150 countries. Nearly 900 active standards with 700 under development. 7/13/2015Wireless Networking J. Bernardini13

IEEE Wireless Standards IEEE 802 project is the most important with multiple working groups – IEEE (Ethernet) – IEEE Wireless LAN (WLAN) – IEEE WiMAX – IEEE Mobile Broadband Most of this course will deal with IEEE /13/2015Wireless Networking J. Bernardini14

IEEE Standards 1997: First ratified ( ) Three ways of implementing a physical communications layer (PHY) – Frequency-hopping spread spectrum (FHSS) – Direct-sequence spread spectrum (DSSS) – Infrared communications (not implemented extensively) All operate at 1Mbps and 2Mbps To be covered in depth is subsequence lessons 7/13/2015Wireless Networking J. Bernardini15

IEEE Amendments IEEE a – OFDM, 5 GHz U-NII, 54 Mbps IEEE b – DSSS, 2.4 Mhz ISM band, 11 Mbps IEEE c – Bridging operation IEEE d – regularity specifications IEEE e – Quality of Service (QoS) IEEE F- access point re-association IEEE g – DSSS/OFDM, 2.4 Mhz, 54 Mbps IEEE h – Dynamic frequency, power control IEEE i – important security enhancements 7/13/2015Wireless Networking J. Bernardini16

IEEE Amendments IEEE j – Mhz band in Japan IEEE k – channel management above 5 Mhz IEEE n –Important 100 Mbps plus WLAN IEEE p –Intelligent Transportation Systems IEEE r – Roaming amendment IEEE s – Extended Mesh network interoperate IEEE T – measurement and test conditions IEEE u – handoffs between WiMax and WLAN IEEE v – device management IEEE w – improved management frames 7/13/2015Wireless Networking J. Bernardini17

More IEEE Standards IEEE 802.1X – port-based authentication for security IEEE Clause 33 – defines power over Ethernet (PoE) IEEE 802.1D – bridging priority IEEE 802.1Q – priority tagging and VLAN FOR QoS 7/13/2015Wireless Networking J. Bernardini18

IETF – International Engineering Task Force Primarily a volunteer organization The most important standards organization for the Internet operation Operates on the basis of the Request-For-Comment (RFC) – IETF issues an RFC in a technical issue – After a period of time all responses to the RFC are gather and voted on WLAN RFC 3748, RFC 2865 are important for wireless – RFC WLAN security – RFC security and the use of RADIUS server 7/13/2015Wireless Networking J. Bernardini19

Wi-Fi Alliance Certification organization for testing and interoperability Eight basic Wi-Fi CERTIFIED TM programs Wi-Fi is just a marketing name; it does not stand for anything Before October 2002 know as the Wireless Ethernet Compatibility Alliance (WECA) Most commercial products will have a Wi-Fi logo for more information 7/13/2015Wireless Networking J. Bernardini20

Wi-Fi CERTIFIED TM Programs IEEE baseline – meets up to IEEE n Wi-Fi Protected Access 2 (WPA2) – based upon IEEE i Wi-Fi Multimedia (WMM)- QoS for various applications WMM Power Save(WMM-PS) – specifications to save battery power Wi-Fi- Protection -Security – Simplified and automated WPA and WPA2 security setup CWG-RF multimedia- defines performance for cellular radios and handsets Voice Personal-application – support for personal and business voice applications 7/13/2015Wireless Networking J. Bernardini21

Communications Models Models are design, management, interoperability and learning OSI Model - seven layers- can be abstract but is very commonly used Core-Distribution-Access Model – a useful model for wireless networking TCP/IP Model - Four layers – good for networks built around TCP/IP 7/13/2015Wireless Networking J. Bernardini22

OSI Model 7/13/2015Wireless Networking J. Bernardini23

Core – Distribution - Access Core Layer – Does not route or manipulate traffic – High speed traffic – think superhighway – Backbone of network – High speed switches and routers Distribution Layer – Routes or directs traffic other nodes – Medium speed traffic – think city traffic – Routers and Bridges Access Layer – directs traffic to end user – Relative slower traffic – think local street traffic – Access Points and Switches 7/13/2015Wireless Networking J. Bernardini24

Core – Distribution – Access Details 7/13/2015Wireless Networking J. Bernardini25

TCP/IP Model 7/13/2015Wireless Networking J. Bernardini26 (Transport)

TCP/IP and OSI Model Maping 7/13/2015Wireless Networking J. Bernardini27

CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini 28 Modulation Carrier signal is a continuous electrical signal – Carries no information Three types of modulations enable carrier signals to carry information – Height of signal – Frequency of signal – Relative starting point Modulation can be done on analog or digital transmissions

CCRI J. Bernardini29 Analog and Digital Modulation Analog Transmission use analog carrier signals and analog modulation. Digital Transmission use analog carrier signals and digital modulation. Modem (MOdulator/DEModulator): Used when digital signals must be transmitted over analog medium – On originating end, converts distinct digital signals into continuous analog signal for transmission – On receiving end, reverse process performed WLANs use digital modulation of analog signals (carrier signal)

CWNA Guide to Wireless LANs, Second Edition CCRI J. Bernardini 30 Analog vs. Digital Transmissions Digital Signal = A signal in which information is carried in a limited number of different discrete states or levels; High/Low, One/Zero, 1/0 Analog Signal = A signal that has continuously varying voltages, frequencies, or phases. All amplitude values are present from minimum to maximum signal levels.

CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini 31 Frequency and Period

CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini 32 Analog Modulation Amplitude: Height of carrier wave Amplitude modulation (AM): Changes amplitude so that highest peaks of carrier wave represent 1 bit while lower waves represent 0 bit Frequency modulation (FM): Changes number of waves representing one cycle – Number of waves to represent 1 bit more than number of waves to represent 0 bit Phase modulation (PM): Changes starting point of cycle – When bits change from 1 to 0 bit or vice versa

CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini 33 Digital Modulation Advantages over analog modulation: – Better use of bandwidth – Requires less power – Better handling of interference from other signals – Error-correcting techniques more compatible with other digital systems Unlike analog modulation, changes occur in discrete steps using binary signals – Uses same three basic types of modulation as analog Amplitude shift keying (ASK)

CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini 34 Digital Modulation Frequency shift keying (FSK) Phase shift keying (PSK)