【正文】 r access ? Bluetooth () ? Links up to 8 devices in 10m area using lowpower, radiobased munication ? Useful for personal working (PANs) Essentials of Business Information Systems Chapter 6 Telemunications, the Inter, and Wireless Technology The Wireless Revolution 169。 2022 by Prentice Hall 所謂藍(lán)牙 (Bluetooth)技術(shù)，實(shí)際上是一種短距離無(wú)線電技術(shù)，利用“藍(lán)牙”技術(shù)，能夠有效地簡(jiǎn)化掌上電腦、筆記本電腦和移動(dòng)電話手機(jī)等移動(dòng)通信終端設(shè)備之間的通信，也能夠成功地簡(jiǎn)化以上這些設(shè)備與 Inter之間的通信，從而使這些現(xiàn)代通信設(shè)備與因特網(wǎng)之間的數(shù)據(jù)傳輸變得更加迅速高效，為無(wú)線通信拓寬道路。 169。 2022 by Prentice Hall A Bluetooth Network (PAN) Essentials of Business Information Systems Chapter 6 Telemunications, the Inter, and Wireless Technology Figure 615 Bluetooth enables a variety of devices, including cell phones, PDAs, wireless keyboards and mice, PCs, and printers, to interact wirelessly with each other within a small 30foot (10meter) area. In addition to the links shown, Bluetooth can be used to work similar devices to send data from one PC to another, for example. The Wireless Revolution 169。 2022 by Prentice Hall ? Wireless puter works and Inter access – WiFi () ? Set of standard: , , , ? Used for wireless LAN and wireless Inter access ? Use access points: Device with radio receiver/transmitter for connecting wireless devices to a wired LAN ? Hotspots: One or more access points in public place to provide maximum wireless coverage for a specific area ? Weak security features 169。 2022 by Prentice Hall An Wireless LAN Essentials of Business Information Systems Chapter 6 Telemunications, the Inter, and Wireless Technology Figure 616 Mobile laptop puters equipped with wireless work interface cards link to the wired LAN by municating with the access point. The access point uses radio waves to transmit work signals from the wired work to the client adapters, which convert them into data that the mobile device can understand. The client adapter then transmits the data from the mobile device back to the access point, which forwards the data to the wired work. The Wireless Revolution 169。 2022 by Prentice Hall ? Wireless puter works and Inter access ? WiMax () ? Wireless access range of 31 miles ? Require WiMax antennas ? Broadband cellular wireless ? Many cell services offer WiFi capabilities for Inter access Essentials of Business Information Systems Chapter 6 Telemunications, the Inter, and Wireless Technology The Wireless Revolution 169。 2022 by Prentice Hall ? Radio frequency identification (RFID) （射頻） ? Use tiny tags with embedded microchips containing data about an item and location ? Tags transmit radio signals over short distances to special RFID readers, which send data over work to puter for processing ? Active RFID: Tags have batteries, data can be rewritten, range is hundreds of feet, more expensive ? Passive RFID: Range is shorter, also smaller, less expensive, powered by radio frequency energy Essentials of Business Information Systems Chapter 6 Telemunications, the Inter, and Wireless Technology The Wireless Revolution 169。 2022 by Prentice Hall ? Radio frequency identification (RFID) ? Common uses: ? Automated tollcollection ? Tracking goods in a supply chain ? Requires panies to have special hardware and software ? Reduction in cost of tags making RFID viable for many firms Essentials of Business Information Systems Chapter 6 Telemunications, the Inter, and Wireless Technology The Wireless Revolution 169。 2022 by Prentice Hall How RFID Works Essentials of Business Information Systems Chapter 6 Telemunications, the Inter, and Wireless Technology Figure 617 RFID uses lowpowered radio transmitters to read data stored in a tag at distances ranging from 1 inch to 100 feet. The reader captures the data from the tag and sends them over a work to a host puter for processing. The Wireless Revolution 169。 2022 by Prentice Hall 169。 2022 by Prentice Hall 169。 2022 by Prentice Hall Reader Tag 169。 2022 by Prentice Hall ? Read the Interactive Session and then discuss the following questions: ? How is RFID technology related to WalMart’s business model? How does it benefit suppliers? ? What people, anization and technology factors explain why WalMart suppliers have had trouble implementing RFID systems? ? What conditions would make adopting RFID more favorable for suppliers? ? Should WalMart require all its suppliers to use RFID? Why or why not? Explain your answer. Interactive Session: Organizations WalMart Grapples with RFID Essentials of Business Information Systems Chapter 6 Telemunications, the Inter, and Wireless Technology The Wireless Revolution 169。 2022 by Prentice Hall ? Wireless sensor works ? Networks of hundreds or thousands of interconnected wireless devices embedded into physical environment to provide measurements of many points over large spaces ? Used to monitor building security, detect hazardous substances in air, monitor environmental changes, traffic, or military activity ? Devices have builtin processing, storage, and radio frequency sensors and antennas ? Require lowpower, longlasting batteries and ability to endure in the field without maintenance Essentials of Business Information Systems Chapter 6 Telemunications, the Inter, and Wireless Technology The Wireless Revolution 169。 2022 by Prentice Hall A Wireless Sensor Network Essentials of Business Information Systems Chapter 6 Telemunications, the Inter, and Wireless Technology Figure 618 The small circles represent lowerlevel nodes and the larger circles represent highend nodes. Lowerlevel nodes forward data to each other or to higherlevel nodes, which transmit data more rapidly and speed up work performance. The Wireless Revolution