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Introduction to Wireless Networking Module-01 Overview of Wireless Standards, Organizations and Technology Jerry Bernardini Community College of Rhode Island 5/25/2017 Wireless Networking J. Bernardini 1 Presentation Reference Material • CWNA Certified Wireless Network Administration Official Study Guide (PWO-104), David Coleman, David Westcott, 2009, Chapter-1 5/25/2017 Wireless Networking J. Bernardini 2 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 5/25/2017 Wireless Networking J. Bernardini 3 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 5/25/2017 Wireless Networking J. Bernardini 4 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) • 802.11 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 5/25/2017 Wireless Networking J. Bernardini 5 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 5/25/2017 Wireless Networking J. Bernardini 6 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 2.483 GHz range) – 5 GHz band, (5.725 to 5.850 GHz range) • 1997: Unlicensed National Information Infrastructure U-NII bands – 5.15 to 5.25 GHz – 5.25 to 5.35 GHz – 5.725 to 5.825 GHz 5/25/2017 Wireless Networking J. Bernardini 7 FCC Unlicensed Bands Advantages •No licenses required •No Fees •No Permits •Comply with rules and build anything 5/25/2017 Disadvantages •Everyone can use the bands •Interference between users •Bandwidth Contention •First-come-first –serve •Interference from latecomers Wireless Networking J. Bernardini 8 FCC Regulates Frequencies • Frequencies are grouped into bands – Wireless LAN bands include: (Hz = Hertz) 5/25/2017 Frequency Band Total Bandwidth License-Free Band 2400–2500 MHz 100 MHz ISM 5.15–5.25 GHz 100 MHz U-NII 5.25–5.35 GHz 100 MHz U-NII 5.470–5.725 GHz 255 MHz U-NII 5.725–5.825 GHz 100 MHz U-NII Wireless Networking J. Bernardini 9 FCC Power Output Limits-U-NI Bands Band Power Output Limits Area Usage U-NII 5.15–5.25 GHz 40 mW Restricted to indoor operations U-NII 5.25–5.35 GHz 200 mW Indoor/outdoor U-NII 5.470–5.725 GHz 200 mW Indoor/outdoor U-NII 5.725–5.825 GHz 800 mW Higher output power assumes outdoor operations mw = 1/1000 watt 5/25/2017 Wireless Networking J. Bernardini 10 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 5/25/2017 Wireless Networking J. Bernardini 11 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 – – – – – 5/25/2017 Region A: The Americas Region B: Western Europe Region C: Eastern Europe Region D: Africa Region E: Asia and Australia Wireless Networking J. Bernardini 12 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. 5/25/2017 Wireless Networking J. Bernardini 13 IEEE Wireless Standards • IEEE 802 project is the most important with multiple working groups – – – – IEEE 802.3 (Ethernet) IEEE 802.11 Wireless LAN (WLAN) IEEE 802.16 WiMAX IEEE 802.16 Mobile Broadband • Most of this course will deal with IEEE 802.11 5/25/2017 Wireless Networking J. Bernardini 14 IEEE 802.11 Standards • 1997: First 802.11 ratified (802.11-1997) • 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 5/25/2017 Wireless Networking J. Bernardini 15 IEEE 802.11 Amendments • • • • • • • • • IEEE 802.11a – OFDM, 5 GHz U-NII, 54 Mbps IEEE 802.11b – DSSS, 2.4 Mhz ISM band, 11 Mbps IEEE 802.11c – Bridging operation IEEE 802.11d – regularity specifications IEEE 802.11e – Quality of Service (QoS) IEEE 802.11F- access point re-association IEEE 802.11g – DSSS/OFDM, 2.4 Mhz, 54 Mbps IEEE 802.11h – Dynamic frequency, power control IEEE 802.11i – important security enhancements 5/25/2017 Wireless Networking J. Bernardini 16 IEEE 802.11 Amendments • • • • • • • • • • IEEE 802.11j – 4.9-5 Mhz band in Japan IEEE 802.11k – channel management above 5 Mhz IEEE 802.11n –Important 100 Mbps plus WLAN IEEE 802.11p –Intelligent Transportation Systems IEEE 802.11r – Roaming amendment IEEE 802.11s – Extended Mesh network interoperate IEEE 802.11T – measurement and test conditions IEEE 802.11u – handoffs between WiMax and WLAN IEEE 802.11v – device management IEEE 802.11w – improved management frames 5/25/2017 Wireless Networking J. Bernardini 17 More IEEE Standards • IEEE 802.1X – port-based authentication for security • IEEE 802.3-2005 Clause 33 – defines power over Ethernet (PoE) • IEEE 802.1D – bridging priority • IEEE 802.1Q – priority tagging and VLAN FOR QoS 5/25/2017 Wireless Networking J. Bernardini 18 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 3748 - WLAN security – RFC 2865 -security and the use of RADIUS server 5/25/2017 Wireless Networking J. Bernardini 19 Wi-Fi Alliance • Certification organization for testing and interoperability • Eight basic Wi-Fi CERTIFIEDTM 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 • www.wi-fi.org for more information 5/25/2017 Wireless Networking J. Bernardini 20 Wi-Fi CERTIFIEDTM Programs • • • • IEEE 802.11 baseline – meets up to IEEE 802.11n Wi-Fi Protected Access 2 (WPA2) – based upon IEEE 802.11i 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 5/25/2017 Wireless Networking J. Bernardini 21 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 5/25/2017 Wireless Networking J. Bernardini 22 OSI Model 5/25/2017 Wireless Networking J. Bernardini 23 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 5/25/2017 Wireless Networking J. Bernardini 24 Core – Distribution – Access Details 5/25/2017 Wireless Networking J. Bernardini 25 TCP/IP Model (Transport) 5/25/2017 Wireless Networking J. Bernardini 26 TCP/IP and OSI Model Maping 5/25/2017 Wireless Networking J. Bernardini 27 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 CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini 28 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 CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini (carrier signal) 29 Analog vs. Digital Transmissions Analog Signal = A signal that has continuously varying voltages, frequencies, or phases. All amplitude values are present from minimum to maximum signal levels. 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 CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini 30 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 CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini (carrier signal) 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) CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini 35 Spread Spectrum Technology Uses • Spread spectrum is a technique of transmitting radio signals over multiple frequencies – The common method of transmitting WLAN signals – Spread Spectrum will be explained in depth in chapter-3 • Spread spectrum is used by – Wireless LANs (WLANs) – Wireless PANs (WPANs) – Wireless MANs (WMANs) Use Examples Range Speeds WLAN /Backhaul IEEE 802.11 375 ft/ miles > 2Mbps WPAN Bluetooth 1-3 meters .723 – 3 Mbps WMAN/ Backhaul WiMax and EDGE 10 km ~ 40 Mbps WWAN / backhaul AT&T microwave ~75-135 kbps 5/25/2017 variable Wireless Networking J. Bernardini 36 Wireless LANs (WLANs) • The major application of IEEE 802.11 • WLANs provide mobility and unwired fixed connectivity • Three primarily roles of WLANs – Access role – Distribution role – Core role 5/25/2017 Wireless Networking J. Bernardini 37 Wireless PANs (WPAN) • Wireless Personal Area Networks • 10 meter radius connectivity • Primarily Bluetooth Applications – headsets – mouse – PDA • Uses 2.4 GHz ISM band which can interfere with 802.11 WLAN 5/25/2017 Wireless Networking J. Bernardini 38 Wireless MANs (WMAN) • • • • • Wireless Metropolitan Area Network Uses both Point-to-Point and Point-to-Multipoint WiMAX and IEEE802.16 Leased networks covering multiple miles Provide QoS mechanisms 5/25/2017 Wireless Networking J. Bernardini 39 Wireless WANs (WWANs) • Expansion of WAN technology – DSL – ISDN – Cable • WWANs connect LANs to backbone • Uses both Point-to-Point and Point-to-Multipoint • WWANs provide multi-channel communications 5/25/2017 Wireless Networking J. Bernardini 40 Last-Mile Delivery • Last mile is the connection between the ISP and the end user – Example: home and telephone central office – Example: Office and Cable provider hub • Last mile comes from the old telephone network design; – max of 18000 ft to central office • Last mile can be expensive • Wireless Internet Service Provider (WISP) • WISP use WiMAX (IEEE 802.16) 5/25/2017 Wireless Networking J. Bernardini 41 Major Wireless Applications • SOHO – Small Office / Home Office – Less than 25 computers – Router connections • Mobile Office Network – Similar the SOHO but mobile – Mobile IP usage • • • • Educational/Classroom Use Hotspots Warehousing and Manufacturing Health Care 5/25/2017 Wireless Networking J. Bernardini 42 Wireless Hotspots • • • • • • Hotspots often use Wi-Fi Free and wide open Free and secure Subscription based Pay-as-you-go Mixed 5/25/2017 Wireless Networking J. Bernardini 43