80211ac

802.11ac is a wireless networking standard in the IEEE 802.11 family, marketed as Wi-Fi 5. It is designed to operate in the 5 GHz radio band and to deliver higher data rates and better performance in dense environments compared with its predecessors.

Key features of 802.11ac include the use of wider channel bandwidths (20, 40, 80, and 160 MHz), higher-order modulation (256-QAM), and multiple-input multiple-output (MIMO) techniques. These enhancements enable greater theoretical throughput and improved spectral efficiency. The technology supports multiple spatial streams, with the number depending on hardware, and is commonly implemented in dual-band devices that also operate in the 2.4 GHz band through legacy standards.

802.11ac is divided into two main generations. Wave 1 introduced wider channels and 256-QAM as well as enhanced MIMO capabilities, delivering substantial throughput gains over 802.11n. Wave 2 added downlink multi-user MIMO (MU-MIMO), support for 160 MHz channels in some configurations, and, in many devices, higher numbers of spatial streams.

Performance claims for 802.11ac are highly situational, with theoretical maximum data rates reaching several gigabits per second under optimal conditions. In practice, real-world speeds are lower and depend on factors such as channel width, interference, and device capabilities.

Security for 802.11ac networks commonly relies on WPA2 (with evolving recommendations for WPA3). The standard remains compatible with existing 802.11 devices in mixed networks, though 5 GHz operation may not be supported by older 2.4 GHz-only equipment. 802.11ac has largely been superseded by newer standards in modern deployments, but remains in use in many networks.

---