The forthcoming (imminent even – with caveats, see “So What” below) wireless spec 802.11ax is a genuinely worthy next generation wireless standard. It has a bunch of substantial improvements over 802.11ac which can be summed up in IEEE’s initial 802.11ax goal to reach for 4x improvement designing for high density scenarios. You’ll run into “4x” a lot in vendor’s marketing. IEEE started it! Talking 4x up back in circa 2014.
I’m pretty keen on how 802.11ax appropriates 4G LTE’s OFDMA and resource scheduling. 802.1ax has jettisoned previous wireless standards’s (802.11ac and prior) method of determining when it’s your turn to transmit, while keeping 802.11ac/n backwards compatibility. This is not a technical blog on Wi-Fi – suffice to say 802.11 standards prior to 802.11ax – very broadly speaking – rely on collision avoidance, waiting (yes waiting), and permission to transmit (request to send) to finally get around to communicating over wireless in the gaps when other clients are quiet. This is a client competition for airtime to send to the AP.
Resource scheduling refers to scheduling client airtime access. Clearly a proven approach for LTE, bring it on for 802.11ax. As well as the other 802.11ax improvements – 802.11ax brings the previously mentioned 4x better throughput in higher density environments; new modulation and coding set 1024-QAM; OFDMA with its attendant benefits; power management improvements for longer client battery life, and up to 8×8 MU-MIMO in both downlink and uplink to support up to 8 users simultaneously. At least they are some of the highlights. Go find a really great technical explanation for more.
Yep. For the moment (measured in say – years) So what. Why?
To get the 4x increase in throughput in high-density wireless environments. Assuming pure 802.11ax AP infrastructure:
- We all need to be using 802.11ax client devices.
- We need to eradicate 802.11ac/n clients from our 802.11ax AP environment.
In conclusion 802.11ax’s improvements will only be realised in a truly pristine 802.11ax only environment across all APs and all client devices. How long before we see that?