Wi-Fi7 – rainbows, unicorns and high performance

Like every technological advancement that leads directly to sales of new hardware, Wi-Fi7 promises to solve all your problems. This, of course, will not happen nevertheless it’s now available ***in draft form*** so should you buy it?

No.

Ok let me qualify that. Not at the moment unless you are buying new Wi-Fi hardware anyway, in which case maybe.

The IEEE specification behind Wi-Fi7 is 802.11be and it isn’t finalized yet. That means any Wi-Fi7 kit you can buy right now is an implementation of the draft specification. Chances are that specification isn’t going to change much between now and when it’s finalised (expected end of 2024) but it could. There’s nothing new here, vendors have released hardware based on draft specs for the last few major revisions of the 802.11 Wi-Fi standards.

Perhaps more important is in a rush to get new hardware on the shelves what you can buy now is a Wi-Fi7 wave1 which doesn’t include some capabilities within the specification. As we saw with 802.11ac (Wi-Fi5) the wave2 hardware can be expected to be quite a lot better – it will support more of the protocol’s options, chances are the hardware will be more power efficient too – personally I’d wait.

Something that’s important to remember about every iteration of Wi-Fi is that it almost certainly won’t magically solve whatever problem you have that you believe is caused by the Wi-Fi. Client support is also very sparse right now, so swapping out your Wi-Fi6 access point/Wi-Fi router for Wi-Fi7 hardware probably won’t make any difference at all.

As with all previous versions many of the benefits Wi-Fi7 brings are iterative improvements that aim to improve airtime usage. These are definitely worth having, but they’re not going to make the huge difference marketing might have you believe.

The possibility of 4096 QAM (subject to really high SNR) allows for higher data rates – all other things being equal. 512 MPDU compressed block-ack is a complex sounding thing that ultimatley means sending a bigger chunk of data at a time and being able to move more data before acknowledging – which is more efficient. Channel bonding is enhanced with 320MHz channels now possible and improvements on how to handle a channel within the bonded range being used by something else. All very welcome (apart from maybe 320MHz channels) and all iterations on Wi-Fi6.

The biggest headline boost to performance in Wi-Fi7 is Multi-Link Operation – MLO. For anyone familiar with link-aggregation, what Cisco calls Port-Channel, the idea of taping together a number of links to aggregate bandwidth across those links as a single logical connection – MLO is basically this for Wi-Fi radios.

That 2.4GHz band that’s been referred to as dead for that last however many years, now can be duct taped to 5GHz channels and you get extra bandwidth for your connection. You might expect you could also simultaneously use 5GHz and 6Ghz and you can… in theory, but none of the vendors offering Wi-Fi7 hardware support that right now. Chances are this is something that will come in the wave2 hardware, maybe a software update…. who knows.

There are benefits to MLO other than raw throughput – a device with two radios (2×2:2) could listen on both 5GHz and 6Ghz (for example) and then use whichever channel is free to send its transmission. This can improve airtime usage on busy networks and reduce latency for the client. Devices switching bands within the same AP can also do so without needing to roam (currently moving from 2.4GHz to 5GHz is a roaming event that requires authentication) and this improves reliability.

Key to MLO is having Multi-Link Devices. Your client needs to support this for any of the above to work.

Wi-Fi7 has a lot to offer, builds on Wi-Fi6 while introducing technology that paves the way for further signficant improvements when Wi-Fi8 arrives. There’s a lot of potential for Wi-Fi networks to get a lot faster with a Wi-Fi7 deployment.

Returning to my initial quesiton… Personally I wouldn’t buy Wi-Fi7 hardware today unless I already needed to replace my equipment. Even then, domestically I’d probably get something to fill the gap until the wave2 hardware arrives. If everything is working just fine but you’d like to get that bit more wireless speed, chances are Wi-Fi7 isn’t going to deliver quite as you might hope. Those super speeds need the client to be very close to the AP.