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Next generation Wi-Fi (802.11ax)
victor
Recently I have heard from different sources about Next generation Wi-Fi – a specification which is coming in December 2018. Some people say it will solve all the problems and limitation of the current specification (802.11ac), but let’s take a closer look.
Some history
If you look at the development of Wi-Fi protocol, the biggest recent advance was 802.11n:
- unified the standard (a/c/g);
- the introduction of MIMO has greatly changed the approaches to radio planning;
- it achieved radically higher speeds, what had led to a revision of the principles of building WLAN – the role of controllers and points changed, as well as the architecture of networks in general;
The next protocol (802.11ac) did not bring anything new, and in many respects, it was simply redundant. New speeds required wide channels, special RF conditions and the absence of “old” 802.11a / n devices. Wi-Fi hub remained just a Wi-Fi hub. And as we know, a hub with a bunch of clients cannot be fast in principle. If we only could switch from hubs to switches.
So what about 802.11ax?
The goal of 802.11ax is to increase not the speed, but the capacity of the network. With the help of the “mature” OFDMA technology (coming from LTE / WiMax), the channel could be “cut” into subchannels and run there as many more clients as it does in cellular communications. Simply saying, in the past, it was difficult to put a GSM base station in a box of the size of an access point, but now it’s quite real 🙂
But as it usually a case – the miracle did not happen, and it probably won’t happen: Wi-Fi hub remains to be just a hub, not a switch. Old limitations are still in place. Welcome back to 1990s!
If you want to know some technical details, I truly recommend reading an excellent article 802.11ax Is Not