Thông qua ứng dụng Facebook, người dùng có thể nhận được một ý tưởng những gì còn lại của thế giới nghĩ và so sánh quan điểm của ông với những người khác. Ngoài việc bỏ phiếu của mình, người sử dụng khác cũng có thể nhận xét về mình | CHAPTER Wireless Data Network Protocols Copyright 2003 by The McGraw-Hill Companies Inc. Click Here for Terms of Use. 38 Part 1 Overview of Wireless High-Speed Data Technology Popular wireless data networking protocols such as Bluetooth IEEE and HomeRF were originally developed for the frequency band by organizations that made design tradeoffs based on values such as complexity price and performance. Because the protocols were developed independently and these values differed according to the markets and applications the organizations intended to serve the various protocols do not easily interoperate with one another and can cause significant mutual interference when functioning in the same radio space. The problem becomes especially acute in environments such as residential networks where a single network may be required to serve a broad range of application classes. A newer high-performance wireless data LAN standard IEEE operates in the 5-GHz band and offers much higher speeds than previous WLAN standards but does not adequately provide for unified networks that support multiple classes of devices with differing speed performance power complexity and cost requirements. These differing classes of devices will become increasingly important as LANs move beyond the limits of office-oriented computer interconnection services and into the realm of data video and audio distribution services for interconnected devices in offices and homes. The Glossary defines many technical terms abbreviations and acronyms used in the book. Nevertheless the data wireless marketplace is booming. New wireless data products are being introduced daily. The unlicensed industrial scientific medical ISM band at the 900-MHz and frequencies creates opportunities for high-quality wireless data products to be introduced. Wireless home networking initiatives are being announced and developed including the BlueTooth HomeRF and IEEE working groups and others. .
