Đang chuẩn bị liên kết để tải về tài liệu:
Five keys to successful PoE deployment
Đang chuẩn bị nút TẢI XUỐNG, xin hãy chờ
Tải xuống
Before 802.3af, vendors and consumers of IP phones were faced with two options: Provide local power through an AC (alternating current) electrical outlet, or use non-standards-based proprietary solutions to provide inline powering. Both choices were equally unappealing. | design Cabling L InstaUationfrMaintenance. Five keys to successful PoE deployment f you were to put together a list of the hottest technologies in today s networking industry WiFi wireless networking and VoIP Voice over Internet Protocol would be near the top. Recently several major corporations announced plans for a global rollout of IP phones. By the same token WiFi hotspots have cropped up everywhere. In addition to being current industry buzzwords WiFi and VoIP also share another common attribute. They both require Ethernet and power to function. In June 2003 the Institute of Electrical and Electronics Engineers IEEE www.ieee.org released IEEE 802.3af also known as the Power over Ethernet PoE standard which was established to provide a universal way to provide power and Ethernet-based data to a remote powered device over standard Ethernet cabling such as Category 5e or Category 6. Before 802.3af vendors and consumers of IP phones were faced with two options Provide local power through an AC alternating current electrical outlet or use non-standards-based proprietary solutions to provide inline powering. Both choices were equally unappealing. The release of 802.3af has enabled technologies such as VoIP and WiFi and has paved the way for literally hundreds of new product ideas that require the combination of both data and power. Examples include radio-frequency identification RFID scanners IPsecurity cameras alarm systems and smart-building controls. Planning for integration Given the future impact PoE-based devices will have on your business it is important to begin planning how JOHN SCHMIDT is a product manager with ADC www.adc.com . Carefully consider the devices capabilities and limitations before putting them to use. to integrate PoE into your current and future network. The IEEE standard recognizes two methods for deploying PoE in your network. The first requires that Ethernet switches inject power and data at the same time. This approach may work well for