【2018-12-17】DFS简单笔记

[历史归档]本文原发布于 cstriker1407.info 个人博客内容为历史存档仅供参考。发布时间2018-12-17 标题DFS简单笔记分类网络通讯 / WIFI 标签802.11·DFSTOC参考【 https://kb.netgear.com/000060371/What-is-Dynamic-Frequency-Selection-and-how-does-it-work-with-my-NETGEAR-router 】【 https://www.wi-fi.org/knowledge-center/faq/what-is-dynamic-frequency-selection-dfs 】【 https://www.networkcomputing.com/wireless-infrastructure/dynamic-frequency-selection-why-its-critical-80211ac 】What isdynamic frequency selection (DFS)?In many countries, regulatory requirements may limit the number of 5 GHz channels available or place additional restrictions on their use because the spectrum is shared with other technologies and services. For instance, in the US and other countries, some of the Unlicensed National Information Infrastructure (U-NII) bands are used by radar systems. Wi-Fi networks operating in those bands are required to employ a radar detection and avoidance capability. The IEEE 802.11h standard addresses this requirement by adding support for DFS andtransmit power control (TPC)on every DFS channel.Dynamic Frequency Selection (DFS) is a legally required feature for all WiFi devices that share the 5 GHz band with radar.The IEEE 802.11 standard allows devices like routers and access points (APs) to share the 5 GHz radio spectrum with radar. Radar signals are vulnerable to interference from other devices using the same spectrum.DFS enables a router or AP to detect radar signals and switch their operating frequency to prevent interference.This process ensures that radar systems send and receive accurate information.