Wave 2 of 802.11ac also introduces a new feature called multi-user multiple-input, multiple-output (MU-MIMO), which utilizes “beamforming.” With MU-MIMO, a Wave 2 802.11ac access point (AP) can send and receive data from up to four radio clients simultaneously. Juxtapose this with a three-stream 802.11n AP or an 802.11ac Wave 1 AP, where each AP can talk to only one client at a time, one after the other. MU-MIMO makes the wireless network much more efficient.
The evolution of WiFi to 802.11ac Wave 2 is a significant step forward for wireless networks. Historically, the wireless network acted very much like a network hub where all of the clients accessing the network shared the available bandwidth. If one of the devices happened to access a bandwidth-consuming application, such as videoconferencing, it would degrade the performance of the network for all users.
The combination of increased speed and MU-MIMO enables 802.11ac Wave 2 APs to deliver performance similar to that of a network switch (Exhibit 2), where bandwidth can be dedicated to individual users. Now, workers can use any application on any device and be assured of consistent application performance.