Slide thông tin di động đại học bách khoa hà nội chương12 mạng không dây wifi wemax

Trường Đại học Bách Khoa Hà Nội Khoa Điện tử Viễn thông Thông tin di động Mobile Communications TS Đỗ Trọng Tuấn Bộ môn Kỹ thuật thông tin Hà Nội, 10-2010 Mạng không dây Wi-Fi , WiMAX ( Wireless Networks) 2 CuuDuongThanCong.com https://fb.com/tailieudientucntt Overview  What is Wireless? The term wireless refers to telecommunication technology, in which radio waves, infrared waves and microwaves, instead of cables or wires, are used to carry a signal to connect communication devices  These devices include pagers, cell phones, portable PCs, computer networks, location devices, satellite systems and handheld digital assistants 3 Wireless Landscape Wireless Technology Transmission Distance Speed Bluetooth PAN :: 1- 10 m Mbps WLAN 802.11b WLAN :: n*10 – 100 m 11 Mbps WLAN 802.11a, g WLAN :: n*10 – 100 m 54/128 Mbps WiMax 802.16 WMAN :: n – n*10 miles 75 Mbps 2G digital cellular WWAN - Nationwide 14 Kbps 2.5G digital cellular WWAN - Nationwide 384 Kbps 3G digital cellular WWAN - Nationwide 2-10 Mbps WiMAX as a last-mile alternative for remote areas not currently served by DSL or cable 4 CuuDuongThanCong.com https://fb.com/tailieudientucntt Wireless Technologies WAN (Wide Area Network) MAN (Metropolitan Area Network) LAN (Local Area Network) PAN (Personal Area Network) PAN LAN MAN WAN Standards Bluetooth 802.11a, 11b, 11g HiperLAN2 802.11 MMDS, LMDS GSM, GPRS, CDMA, 2.5–3G Speed < Mbps - 54 Mbps 75 Mbps 9,6 Kbps – 2Mbps Range Short Medium Medium–Long Long Last Mile Access PDAs, Mobile Phones, Cellular Access Applications Peer-to-Peer Family, Office, Device-to-Device and Enterprise 5 Mạng không dây Wi-Fi IEEE 802.11 6 CuuDuongThanCong.com https://fb.com/tailieudientucntt Wi-Fi™ and IEEE 802.11 Standards  802.11a: 5GHz, 54Mbps  802.11b: 2.4GHz, 11Mbps  802.11d: Multiple regulatory domains  802.11e: Quality of Service (QoS)  802.11f: Inter-Access Point Protocol (IAPP)  802.11g: 2.4GHz, 54Mbps  802.11h: Dynamic Frequency Selection (DFS) and Transmit Power Control (TPC)  802.11i: Security  802.11j: Japan 5GHz Channels (4.9-5.1 GHz)  802.11k: Measurement  IEEE 802.11n : adding multiple-input multiple-output (MIMO) 7 Wi-Fi™ and IEEE 802.11 Standards 8 CuuDuongThanCong.com https://fb.com/tailieudientucntt Unlicenced Frequency Bands ISM : Industrial, Scientific and Medical U-NII : Unlicenced National Information Infrastructure  Defined cable-free local area network with either fixed or mobile locations that transmit at either or Mbps which was insufficient for most network applications  A new standard was developed for sending packetsized data traffic over radio waves in the unlicensed 2.4 Ghz band  Unlicensed, means it does not have to be certified by the FCC, and devices could possible share the bandwidth with other devices such as cordless phones, oven etc 9 Frequency Bands 10 10 CuuDuongThanCong.com https://fb.com/tailieudientucntt Standard Selection 11 11 Standard Selection 802.11b 802.11a 802.11g Frequency Band 2.4 GHz GHz 2.4 GHz Availability Worldwide US/AP Worldwide 11 Mbps 54 Mbps 54 Mbps HyperLAN Devices Cordless Phones Microwave Ovens Wireless Video Bluetooth Devices Maximum Data rate Other Services (Interference) Cordless Phones Microwave Ovens Wireless Video Bluetooth Devices The Laws of Radio Dynamics: Higher Data Rates = Shorter Transmission Range Higher Power Output = Increased Range, but Lower Battery Life Higher Frequency Radios = Higher Data Rates Shorter Ranges 12 12 CuuDuongThanCong.com https://fb.com/tailieudientucntt Ad Hoc Topology Cấu hình tùy biến (không phụ thuộc) IBSS  Peer-to-Peer (Ad Hoc) Topology  Can consist of or more PCs with wireless network adapters  Sometimes called an Independent BSS (IBSS)  Limited range No AP is needed ! 13 13 Ad Hoc Topology 14 14 CuuDuongThanCong.com https://fb.com/tailieudientucntt Infrastructure Topology Cấu hình phụ thuộc - BSS AP is needed ! 15 15 Infrastructure Topology 16 16 CuuDuongThanCong.com https://fb.com/tailieudientucntt Radio Signal Interference Since the frequency is unlicensed, any device operating in the 2.4 GHz spectrum may cause network interference with a 802.11b wireless device Some devices that may prove troublesome include 2.4 GHz cordless phones, microwave ovens, adjacent public hotspots, and neighboring 802.11b wireless LANs 17 17 WLAN Devices AP : Điểm truy nhập Access Points In-building Infrastructure Bridge, Repeater 18 18 CuuDuongThanCong.com https://fb.com/tailieudientucntt WLAN Devices Clients Antenna • 2.4 GHz client adapter (802.11b,g) • GHz client adapter (802.11a) • PCI card for Desktop • 2.4GHz • GHz Antennas • PCMCIA card for Laptop (Personal Computer Memory Card International Association ) • USB card for Desktop & Laptop 19 19 WLAN Devices Optional 2.4GHz Antennas for Long Range • 13.5 dBi Yagi Distances over 7.3 miles @ Mbps 11.7 Km @ Mbps 3.6 miles @ 11 Mbps 5.8 Km @ 11 Mbps • 21 dBi Solid Dish For distances up to 25+ miles @ Mbps 40+ Km @ Mbps 20.5 miles @ 11 Mbps 33 Km @ 11 Mbps Note: Distances include 50 feet of low loss cable and 10 dB fade margin 20 CuuDuongThanCong.com https://fb.com/tailieudientucntt WiMAX: History  2001:802.16 (interest : 10-66GHz, line of sight, point to point applications)  2003: 802.16a standard (interest: 2-11GHz, NLOS point to multi-point applications, upto 75MHz)  2004: 802.16d ( upgrade of 802.16a, modifications and interoperability )  2005: 802.16e ( offers mobility at vehicular speed) 35 35 Some Technical Specs on WiMax 36 36 CuuDuongThanCong.com https://fb.com/tailieudientucntt 37 37 WIMAX TOWER WIMAX RECEIVER 38 38 CuuDuongThanCong.com https://fb.com/tailieudientucntt WiMax 39 39 WiMAX network architecture 40 40 CuuDuongThanCong.com https://fb.com/tailieudientucntt 802.16 Protocol Architecture  IEEE 802.16 Protocol Architecture has layers: Convergence, MAC, Transmission and physical, which can be mapped to two OSI lowest layers: physical and data link 41 41 802.16 Protocols Architecture 42 42 CuuDuongThanCong.com https://fb.com/tailieudientucntt types of Scheduling Service     Unsolicited Grant Service (UGS)  Real-time, periodic fixed size packets (e.g T1 or VoIP)  Restrictions on bw requests Real-Time Polling Service (rtPS)  Real-time, periodic variable sizes packets (e.g MPEG)  BS issues periodic unicast polls Non-Real-Time Polling Service (nrtPS)  Variable sized packets with loose delay requirements (e.g FTP)  BS issues unicast polls regularly Best Effort Service  Never polled individually 43 43 Connections  802.16/WiMAX is connection oriented  For each direction, a connection identified with a 16 bit CID  Each CID is associated with a Service Flow ID (SFID) that determines the QoS parameters for that CID 44 44 CuuDuongThanCong.com https://fb.com/tailieudientucntt QoS Mechanism 45 45 WiMAX & Wi-Fi WiMAX Wi-Fi Urban WiMAX WiMAX Rural Wi-Fi Wi-Fi Suburbs Urban 46 46 CuuDuongThanCong.com https://fb.com/tailieudientucntt Intel WiMAX Vision Wi-Fi Nomadic Broadband Broadband Access for Enterprise complementary to 3G, EDGE & WiFi 802.16-2004 802.16-e Broadband Access for Public hotspots Wi-Fi Broadband Access @ Home 802.16-2004 complementary to DSL & Cable 802.16-2004 WiFi *Other brands and names are the property of their respective owners 47 47 FUTURE OF WiMAX  WiMax will be deployed in three stages:  In the first phase WiMaX technology (based on IEEE 802.162004) provides fixed wireless connections  In the second phase WiMaX will be available as a cheap and self-installing Subscriber Terminal (ST), linked to PC and to antenna  The third phase enables portability, thus WiMAX (based on IEEE 802.16e) will be integrated into commercial laptops 48 48 CuuDuongThanCong.com https://fb.com/tailieudientucntt Mobile Broadband Technology map IP Based Convergence Wi-Max IP Core Wi-Max 802.16d 802.16e Backhaul Wi-Fi 802.11 Rural Sub-Urban In-Building Hotspots Urban MACRO PICO Access MICRO Cellular Mobility GSM (EDGE) & UMTS (HSDPA) IS-95, CDMA2000 49 49 1x HRPDA EVDO CDMA 3GPP2 2000-1X 1x EVDV 1x EVDV Rel C Rel D Metro Area Nomadic GSM GPRS EDGE UMTS HSPA 4G Air Interfaces MOBILE BROADBAND 3GPP LTE 802.16e (Mobile WIMAX) Mobile Industry 802.16a/d (Fixed NLOS) Fixed Wireless Industry Local Area Fixed Coverage/Mobility Wide Area Mobile Key technologies are evolving to meet the Wireless Broadband Requirements Dial Up 802.16 (Fixed LOS) DSL Experience 802.11n (smart antennas) 802.11 Mesh extns 802.11b/a/g Data Rates (kbps) Higher Data Rate / Lower Cost per Bit 100,000 + 50 CuuDuongThanCong.com https://fb.com/tailieudientucntt WMAX/LTE Specifications Radio Access Network + + + + Packet Core + New all IP collapsed architecture OFDMA Technology Downlink 100Mbps+ Uplink 20-50Mbps+ User