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Comment by samMouret | Hacker News Reader

Wireless is OK, you just need to use it correctly.

The trick is to treat it as a cellular system, and use the same methodology used to build cellular networks:

(1) Use only 5GHz for Wi-Fi. Turn off 2.4GHz WiFi - it's an overloaded, noisy spectrum band.

(2) One router per room, alternating channels between rooms.

(3) Use MU-MIMO (802.11ac gen2) or 802.11ax. The efficient MTU for Wi-Fi is much much larger than the MTU used for real time communication. MU-MIMO lets you send multiple small packets destined for multiple users inside one big wifi frame.

(4) Don't use mesh devices. They multiply the "airtime" of each packet by x2-x4 depending on number of hops and number of packet retries.

(5) Leave 2.4GHz for Bluetooth, and "junk" ISM devices (microwave oven, very-low bandwidth devices, etc).

People push wireless to the breaking point, then complain it's broken...

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>(1) Use only 5GHz for Wi-Fi. Turn off 2.4GHz WiFi - it's an overloaded, noisy spectrum band.

This is an extremely bad idea in some countries, or if you’re not careful which channel you select. In nearly all countries some of the 5ghz channels are shared with RADAR and require DFS. In some countries (eg Germany) all of the channels do.

The idea behind DFS is to detect radar pulses and then shut down the network for a period of time, this can be triggered by radar or interference.

Radar/DFS is a whole other can of worms.

My rules of thumb for DFS:

(1) If you can use a DFS channel - use it. it's usually less congested than the regular channels

(2) If you're unlucky and DFS is triggered once per month or more, try repositioning the AP or changing the AP model to one less sensitive to radar pulses

(3) If no luck - use one of the non-DFS channels. Every country has those. In Germany, that would be channels 32-48 or 149+

Note that DFS (5.4GHz) is for weather radar. In some countries it's operated only in winter season. You may want to use different channels in summer and in winter :)

I ended up switching to 2.4GHz due to interference and have had substantially better performance since. 5GHz is overloaded in my apartment block.

"Ok" is worse than great (which is what you get with wired setups, all the time every time).

I understand your rationale, and I also like the convenience of wifi when it works. That being said, if you can wire "that thing" (whatever it is), just do it. One afternoon of wiring and it will work great for the rest of time. The trade-off is definitely worth it in my experience.

Well that was a long "just". Installing a few sockets and a switch ist much less effort.

> (2) One router per room, alternating channels between rooms.

That isn't realistic for most people, though.

Use power line then - and you probably wont need a router in every room

In my experience, it's not reliable enough. Sometimes it's great, but sometimes it stops working for a few solid seconds. I think it's when the AC starts up.

Anecdata, but my experience with powerline networking in a house with relatively new wiring was that wifi performs better and more reliably.

All good advice, but you forgot to account for the apartment building situation. Your neighbours could be screwing it up for everyone else.

Thus recommendation #1 - Use 5GHz only.

5GHz propagation across walls is much worse than 2.4GHz propagation, therefore only nearby neighbors may interfere with your access point, and on 5GHz there are enough non-overlapping channels to choose an alternate channel avoiding this interference completely.

WiFi analyzer shows about 26 access points on 5 GHz that aren't mine.

I agree it should be much better than 2.4 GHz -- only 2 of my neighbors are stronger than -70 dBm -- but more channels would be nice.

(I guess 6 GHz could help, but then I'll have to upgrade all my clients, too.)

There really aren't when you have 2x80Mhz on either side of you leaving only DFS which can be tricky since a lot of older consumer routers didn't support it. WiFi 6E should help as the allocation is massive with less propagation.

160MHz channels are a rarity even today, neither the latest Samsung S10 nor the latest iPhone support 160MHz.

Much more common is 80MHz channel, and even then, there is a distinction between the "main" 40MHz and the "secondary" 40MHz sub-channel. If you monitor the packets over the air, you'll notice that the secondary channel is much less occupied - all mobile devices switch to 40MHz to save considerable power, unless downloading a big file.

In the US, there are 6 available 80MHz channels, which is more than needed (think 4-color graph coloring).

All of it is true, but before going multiple APs, you should make sure you really need it - you would need to manage multiple networks and getting the APs to work together and allow devices to roam seamlessly might be a pain.

This is where the mesh units might come in handy - they are managed and configured in a single place, and can work together nicely - but of course you have to set them up with wire backhaul instead of in the "mesh mode".

I agree. "Mesh node" with wire backhaul is good and usually solves the seamless roaming issue (YMMV, check before you buy).

That isn't mesh that's just how wifi is designed to work, with a wired DS (Distribution System) Mesh uses radio for the DS

> (1) Use only 5GHz for Wi-Fi. Turn off 2.4GHz WiFi - it's an overloaded, noisy spectrum band.

Even recent low-end phones sometimes have just 2.4GHz Wi-Fi. Even if all you devices support 5 GHz, running 5GHz-only wi-Fi may cause problems to your guests.

That would be great if you can afford so many access points, all your clients support 5 GHz, and you are able to run Ethernet to the access point in each room.

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