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HiveCast Episode 2: 802.11ax Discussion with David Coleman

In this episode of HiveCast, Bradley is joined by David Coleman (CWNE #4) to discuss bad Wi-Fi deployments in hotels, and what’s coming with 802.11ax. Links @mistermultipath CWNA Study Guide Aerohive’s 11ax Content  

How Does BSS Coloring Work in 802.11ax?

A basic service set (BSS) is the cornerstone topology of any 802.11 network. The communicating devices that make up a BSS consist of one AP radio with one or more client stations. In the last blog, we discussed how BSS color is a numerical identifier of a BSS. BSS color, also known as BSS coloring, […]

What is BSS Color in 802.11ax?

As we discussed in the last few blogs, Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) dictates half-duplex communications, and it says only one radio can transmit on the same channel at any given time. An 802.11 radio will defer transmissions if it hears the PHY preamble transmissions of any other 802.11 radio. Unnecessary medium contention […]

802.11ax and Medium Contention

As many of you might already know, a key efficiency enhancement for 802.11ax will be the use of OFDMA by Wi-Fi radios. Orthogonal frequency-division multiple access (OFDMA) is a multi-user version of the OFDM digital-modulation technology and is used in other wireless technologies such as LTE. OFDMA subdivides a channel into smaller frequency allocations, called […]

How Do 20 MHz-Only Clients Operate In 802.11ax?

Much of the 802.11ax draft amendment has been written with Internet of Things (IoT) devices in mind. The radio chipsets used for IoT devices generally need to be low-cost and consume very little power. Traditionally, Bluetooth and Zigbee chipsets have been cheaper to manufacture for IoT devices than Wi-Fi radio radios. However, 802.11ax lays the […]

What Does Multi-User (MU) Mean?

The term multi-user (MU) simply means that transmissions between an AP and multiple clients can occur at the same time dependent on the supported technology. However, the MU terminology can be very confusing when discussing 802.11ax. MU capabilities exist for both OFDMA and MU-MIMO. 802.11ax defines the use of two multi-user technologies, OFDMA and MU-MIMO. But please […]

802.11ax Frame Aggregation Enhancements

The primary goal of both 802.11n and 802.11ac was to provide high throughput and bigger data rates. However, frame aggregation is one key aspect of 802.11n/ac that did enhance airtime efficiency. Frame aggregation is a method of combining multiple frames into a single frame transmission. Fixed MAC layer overhead and medium contention overhead are reduced, […]

802.11ax Frequently Asked Questions

This article covers what the 802.11ax standard is and some common questions regarding this new standard and its accompanying features. Answers Compiled by: David Coleman, CWNE #4 Perry Correll, Aerohive’s IEEE and WiFi Alliance representative Gregor Vucajnk, CWNE #96 1. What is 802.11ax? 802.11ax is an IEEE draft amendment that defines modifications to the 802.11physical […]

Why Is OFDMA One Of The Most Important Features In 802.11ax?

Last week, I wrote about Target Wake Time (TWT), and how it was a key feature for IoT and mobile devices in 802.11ax. As exciting as that feature is, OFDMA is arguably the most important new feature correlated to 802.11ax. As a refresher, OFDMA stands for orthogonal frequency division multiple access. OFDMA is a multi-user version of […]

Does Wi-Fi Architecture Matter In 2018?

Last week, I looked at how to avoid RF interference in WLAN deployments. While this is something that affects everyone that uses Wi-Fi, the architecture your network uses is something that you can control (based on which vendor you choose). One of the primary differences between WLAN architectures is where and how the system is controlled. […]