CWNA Guide to Wireless LANs, Second Edition Chapter Twelve Personal, Metropolitan, and Wide Area Wireless Networks

CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini Wireless Networks Wireless networks classified into four broad categories: Wireless personal area network (WPAN): Hand-held and portable devices; slow to moderate transmission speeds Wireless local area network (WLAN): i.e., IEEE 802.11a/b/g Wireless metropolitan area network (WMAN): Range up to 50 kilometers Wireless wide area network (WWAN): Connects networks in different geographical areas CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini

Wireless Networks Coverage CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini

Point-to-point and Point-to-multipoint Networks Point-Point Point-to-multipoint CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini

Wireless Personal Area Networks-WPAN WPANs encompass technology designed for portable devices PDAs, cell phones, tablet or laptop computers Low transmission speeds Three main categories: IEEE 802.15 standards (Bluetooth) Radio frequency ID (RFID) IrDA CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini

CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini IEEE 802.15.1 (Bluetooth) Bluetooth uses short-range RF transmissions Users can connect wirelessly to wide range of computing and telecommunications devices Rapid and ad hoc connections between devices 802.15.1 adapted and expanded from Bluetooth Designed for area of about 10 meters Rate of transmission below 1 Mbps Up to 1 mw power consumption Two types of 802.15.1 network topologies Piconet Scatternet CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini

CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini Piconet: IEEE 802.15.1 Piconet: When two 802.15.1 devices come within range, automatically connect Master: Controls wireless traffic Slave: Takes commands from master Piconet has one master and at least one slave Active slave: Connected to piconet and sending transmissions Parked slave: Connected but not actively participating CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini

CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini Scatternet IEEE 802.15.1 Modes Devices in piconet can be in one of five modes: Standby: Waiting to join a piconet Inquire: Device looking for devices to connect to Page: Master device asking to connect to specific slave Connected: Active slave or master Park/Hold: Part of piconet but in low-power state Scatternet: Group of piconets in which connections exist between different piconets 802.15.1 uses FHSS CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini

CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini IEEE 802.15.1 speed Comparison CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini

CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini IEEE 802.15.3 Created in response to limitations of 802.15.1 High-rate WPANs Two main applications: Video and audio distribution for home entertainment systems High-speed digital video transfer High-density MPEG2 transfer between video players/gateways and multiple HD displays Home theater PC to LCD projector Interactive video gaming High speed data transfer CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini

CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini IEEE 802.15.3 Modes Differences between 802.15.3 and 802.15.1 Quality of Service (QoS) Security High data rates Spectrum utilization Coexistence Table 12-2: IEEE 802.15.3 security modes CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini

CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini IEEE 802.15.3a, b ,c 802.15.3a: Will support data transfers up to 110 Mbps between max of 245 devices at 10 meters Ultrawideband (UWB) Intended to compete with USB 2.0 and FireWire IEEE 802.15.3b task group working on improving implementation and interoperability of 802.15.3 IEEE 802.15.3c task group developing alternative physical layer standard that could increase speeds up to 2 Gbps CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini

CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini IEEE 802.15.4 Sometimes preferable to have low-speed, low-power wireless devices Size can be dramatically reduced IEEE 802.15.4 standard addresses requirements for RF transmissions requiring low power consumption and cost Table 12-3: IEEE 802.15.4 data rates and frequencies CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini

CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini IEEE 802.15.4 ZigBee ZigBee Alliance: Industry consortium that promotes 802.15.4 standard Figure 12-7: ZigBee and IEEE 802.15.4 CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini

CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini Radio Frequency ID Passive RFID tags: No power supply Can be very small Limited amount of information transmitted Active RFID tags: Must have power source Longer ranges/larger memories than passive tags CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini

CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini IrDA Infrared Data Association IrDA specifications include standards for physical devices and network protocols they use to communicate Devices communicate using infrared light-emitting diodes Recessed into device Many design considerations affect IrDA performance IrDA diodes in device CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini

CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini IrDA Drawbacks IrDA drawbacks: Designed to work like standard serial port on a personal computer, which is seldom used today Cannot send and receive simultaneously Strong ambient light can negatively impact transmissions Angle and distance limitation between communicating devices CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini

Wireless Metropolitan Area Networks Cover an area of up to 50 kilometers (31 miles) Used for two primary reasons: Alternative to an organization’s wired backhaul connection i.e., T1, T3, T4 lines Fiber Optics Very expensive to install backhaul connections Often less expensive to use a WMAN to link remote sites CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini

Wireless Metropolitan Area Networks - WMAN Used for two primary reasons Used to cover area of 50km (31 miles) Used to replace leased lines, T1 and T3 Use to replace typical fiber ($200,000/mile) Use to replace city fiber (up to $3M/mile) Overcome last mile connection Connection that begins at a fast Internet service provider, goes through local neighborhood, and ends at the home or office Slower-speed connection is a bottleneck for users CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini

Wireless Metropolitan Area Networks: Free Space Optics Optical, wireless, point-to-point, line-of-sight wireless technology Able to transmit at speed comparable to Fiber Optics Transmissions sent by low-powered IR beams Advantages compared to fiber optic and RF: Lower installation costs Faster installation Scaling transmission speed Good security Atmospheric conditions can affect transmission CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini

Local Multipoint Distribution Service (LMDS) LMDS provides wide variety of wireless services High-frequency, low-powered RF waves have limited range Point-to-multipoint signal transmission Signals transmitted back are point-to-point Voice, data, Internet, and video traffic Local carrier determines services offered Support up to 16,000 telephone calls For 51 to 155 Mbps over 8km(5miles) LMDS network is composed of cells Cell size affected by line of site, antenna height overlapping cells, and rainfall CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini

Multichannel Multipoint Distribution Service (MMDS) Many similarities to LMDS Longer range than LMDS Lower vulnerability to weather than LMDS Lower cost than LMDS Requires line of sight Normally not encrypted 1.5 Mbps downstream transmission, 300Kbps upstream transmission, up to 56km (35 miles) Receiving end uses pizza box antenna In homes, alternative to cable modems and DSL service For businesses, alternative to T1 or fiber optic connections MMDS hub typically located at a very high point On top of building, towers, mountains CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini

CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini IEEE 802.16 (WiMAX) WiMAX –Worldwide Interoperability for Microwave Access Highest potential of all WMAN technology Can connect IEEE 802.11 hotspots to Internet Can provide alternative to cable and DSL for last mile connection Up to 50 kilometers of linear service area range Does not require direct line of sight Shared data rates up to 70 Mbps (T1 for up to 60 businesses) Longer range than IEEE 802.11 a/b/g Uses scheduling system Device competes once for initial network entry (unlike CDMA/CD and CDMA/CA) A dynamic time slot is assigned to a device All other devices must wait their turn CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini

CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini IEEE 802.16 and 802.20 IEEE802.16 currently only devices addresses in fixed positions 802.16e will add mobile devices to the standard IEEE 802.20 standard: Sets standards for mobility over large areas (will permit 75 to 93 mph roaming) DEPLOYMENT CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini

Wireless Wide Area Networks (WWANS) Wireless networks extending beyond 50 kilometers (31 miles) Two primary technologies: Digital cellular telephony Satellites CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini

Digital Cellular Telephony Two keys to cellular telephone networks: Coverage area divided into cells Cell transmitter at center Mobile devices communicate with cell center via RF Transmitters connected to base station, Each base station connected to a Mobile Telecommunications Switching Office (MTSO) Link between cellular and wired telephone network All transmitters and cell phones operate at low power Enables frequency reuse CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini

Digital Cellular Telephony Frequency reuse CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini

Digital Cellular Telephony Has evolved since 1980 (analog) Now uses digital packet-switch technologies Reuses frequency channels- up to 416 channels 2G –packet switch -GSM 2.5 G - CDMA and GPRS networks 3.0 G -data rate of above 144 kbit/s –EDGE, CDMA200, 1x-RTT CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini

CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini Satellites Satellite use falls into three broad categories: Acquire scientific data, perform research Examine Earth Military and weather satellites “Reflectors” Relay signals Communications, navigation, broadcast CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini

Satellites –Three Categories Satellite systems classified by type of orbit: Low earth orbiting (LEO): Small area of earth coverage Up to 225 satellites needed for total coverage of earth Must travel very fast Medium earth orbiting (MEO): Larger area of coverage than LEO Do not need to travel as fast Geosynchronous earth orbiting (GEO): orbit matches earth’s rotation “Fixed” position Very large coverage area CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini

Satellite –Low earth orbiting - LEO Orbit Altitude -- 321 to 1,448 km (200 to 900 miles) Orbit Speed -- 27,359 kph (17,000 mph) Orbit Time -- 90 minutes Round trip time delay– 20 to 40 milliseconds Total earth coverage –50 to 225 satellites CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini

Satellite –Medium earth orbiting - MEO Orbit Altitude – 2,413 to16,090 km (1,500 to 10,000 miles) Orbit Speed -- Orbit Time – 12 hours Round trip time delay – 50 to 150 milliseconds Total earth coverage –10 to 20 satellites CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini

Satellite –Geosynchronous earth orbiting - GEO Orbit Altitude – 35,860 km(22,282 miles) Orbit Speed – fixed over a point Orbit Time – fixed Round trip time delay – 250 milliseconds Total earth coverage –three satellites (less polar regions) Life – 12 to 15 years CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini

The Future of Wireless Networks IEEE 802.11 subcommittees currently at work: 802.11d: Supplementary to 802.11 MAC layer Promote worldwide use of 802.11 WLANs 802.11f: Inter-Access Point Protocol (IAPP) Will assist with faster handoff from one AP to another 802.11h: Supplement to MAC layer to comply with European regulations for 5 GHz WLANs 802.11j: Incorporates Japanese regulatory extensions to 802.11a standard 802.11n: WLAN in 2008? 802.11s: Defines a mesh wireless network Devices configure themselves and are intelligent CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini