this post was submitted on 21 Feb 2026
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Nobody wants my info dump. I know way too much about networking and computers. The topics are massively deep, like iceberg levels of deep. One for each topic.
I could lecture for an entire day on the nuance and considerations of picking a Wi-Fi channel, or you can ignore me and just hit "auto" which may or may not take some, or all, of my considerations into account when selecting a channel.
If anyone is keen to hear some generally good advice about home networking, here's my elevator speech:
Wire when you can, wireless when you have to. Wi-Fi is shared and half duplex, every wired connection is exclusive to the device and full duplex. If you can't Ethernet, use MoCA, or powerline (depending on what internal power structures you have, this can be excellent or unusable, keep your receipts). Mesh is best with a dedicated backhaul, better with a wired backhaul. Demand it from any system you consider. The latest and greatest Wi-Fi technology probably won't fix whatever problem you're having, it will only temporarily reduce the symptoms and you won't notice it for a while. Be weary about upgrading and ask yourself why you require the upgrade. Newer wireless won't fix bad signal, or dropouts.
For everything else, Google. That's how I find most of the information I know.
Good luck.
I'll be around in case anyone has questions. No promises on when I'll be able to reply tho.
Dude these type of replies are what had made reddit such a great time sink, even random browsing you may find something incredible in the comments. Thank you
Thanks. I've been on hiatus for a bit. I'm around.
I still won't go back to that place either way
If you can't run cables through your walls you could look into fiber that hides in plain sight https://youtu.be/Z2FbzCyiNr4
5 or 6Ghz backhaul on the mesh?
Should I buy consumer or small business hardware?
Recommended brand(s)?
High end consumer aka prosumer, which is only really one brand, ubiquiti. Specifically their unifi stuff.
Or used mid range business stuff, Cisco, Aruba, juniper. The pinch here is that you usually need specialized knowledge to configure this class of device. I've also used Cisco, watchguard, Fortinet, Sophos, sonicwall, and probably others for firewalls. I prefer Sonicwall for some very specific reasons about how they structure their configuration, but for anyone who isn't a certified sonicwall tech, I'd point at Sophos. Their stuff seems to be a fair balance of configurability and user friendliness. If you're instant on new business stuff and you have the money for it, Sophos for the firewall, Aruba instanton for switching and Wi-Fi.
The benefit to unifi is user friendliness and a unified control console. If you're not an IT professional or a similar technical job, unifi will provide plenty of what you need and leave out the unnecessary knobs that needs like me want to see.
Be prepared to spend several hundred on the networking if you're going to do it right, there are some places you can trim some costs, but before you nope it from sticker shock, consider how much you spend per year on Internet service, and then consider how much the router/firewall + switch + access points are in comparison... And those are things you don't need to buy every year.
Love the Unifi gear; their first gen stuff used isn’t terribly priced. And the single pane of glass is very nice.
Tell Me everything you want about MAC addresses
Is this a kink?
The first six hexadecimal digits of the Mac address are referred to as the oui, or organizationally unique identifier. They are supposed to all be registered, but with modern systems, mac address randomization is common, so the Mac address in use can be little better than nonsense.
I have a theory that some of the more budget oriented manufacturers (think Ali express), just don't bother using a registered mac address at all.
This all makes my job harder as a network admin, I usually need to look up what a device is by mac address to help identify what it is and what it's doing. I need to make sure everything is on the right network, and I can't do that if I don't know what anything is.
The last six hexadecimal digits of the Mac are simply to uniquely identify the interface that the Mac is burned into. This also means that any systems with multiple network ports, have different mac address on each port. Some things are exempt, like network switches, but for the most part, every interface has, or is supposed to have, a unique mac address.
Also, the mac isn't hex, it's binary. Hex is just how we've decided to present it to users. The switches, routers, and interfaces don't work with the hex, only the binary. Same for IP addresses, which normal are shown in "dotted decimal notation", but are just binary. But you didn't ask about IP.
Did you need me to whisper ouis into your ear and you can guess what company is registered to that oui?
Fun fact, when I worked for Alstom and programmed their electric substations, they had a 10bit network and proprietary network cards, and the prototypes sometimes had the same MAC address 😁😅
Nothing sexier than someone who knows what they're talking about.
Sorry, I'm married.
:p
My wife doesn't think it's sexy, she usually just falls asleep whenever I get into a topic I'm passionate about. Oh well.
So if you plug the same device into a different network using the same port, it's the same MAC?
The device mac doesn't change unless mac randomization is on.
I hate that, as far as I know, on Android you can't choose the "randomized" MAC
The MAC, at least as it was conceptualised (as they said, MAC randomisation etc. mess with this), is a unique identifier for that specific device. It doesn't change, and only one device has that specific MAC.
Or more specifically, that specific network adaptor, the hardware responsible for connecting to networks. So one computer might have multiple MACs if, for example, it has an Ethernet port and a wifi card.
Would like to ask, is it worth entering networking as a career right now? I've been of the belief that it'll be necessary as long as the internet is around, so certainly within my lifetime, but the current AI bubble and the direction it's taking is making me think otherwise.
Networking is a pretty specific niche, the biggest challenge I've faced in my career is that I can't find any local jobs, or remote work positions that are networking focused. It's still a passion of mine, but I tend to be stuck in sysadmin type roles.
As far as I'm concerned, until AI can plug itself in and fix it's own servers, humans will always need to be involved in the setup and maintenance of the hardware that connects our world. I don't think it's practical or realistic for AI to put satellites in orbit or run intercontinental fiber along the ocean floor. Not anytime soon and not in our lifetimes.
The thing about computers is that they're not very adaptable to their environment, so the environment needs to be adapted to computers. We, as humans, are extremely adaptable to our environment. This is very slowly shifting that computers are starting to be able to adapt to different working environments; but I don't think that will happen in fully within our lifetimes.
Programming can be a minefield right now, but that shouldn't dissuade you if that's your interest/passion. Networking will be required, and tech jobs are some of the most recession proof, though not completely recession proof. Tech fields have slowed but it's extremely rare that we see negative growth in tech. The players might change but the jobs are there and need people in chairs to fulfill them.
My advice is to pursue what interests you, and adapt to whatever life throws at you. Maybe you'll start with cybersecurity and move into a coding role, or like me, study networking and then work as a generalist. When you get to that point, when interviewing for jobs, make sure you know what the job is, review the job posting with your interviewer if you are uncertain at all. The job should fit you as much as you fit it. I didn't do that for one job and it was one of the most unpleasant years of my life working there. I got on the job and discovered that what I thought I'd be doing, was not what I was going to be doing.
Good luck.
What are the nuances between APs and how they handle choosing a channel? Also, I was told at one point it’s better to “stack” on top of other SSIDs using the same channel than to go one channel higher (assuming there isn’t room higher up in the spectrum).
Thank you for your time and expertise!
I can answer the second thing quickly, "stacking" the ssids as you say, makes the inference into what we call "co-channel" interference. Most of the wireless headers are unencrypted, though your payload is encrypted (the data being transferred) but not so much for the headers. Because of this, and the fact that each ap is talking on the same frequency, there's a small amount of collaboration that can occur between wireless networks. If someone starts a wireless multimedia (WMM) session that will last 8.2ms, then all radios on channel will know that the channel is occupied for the next 8.2ms, and basically go idle for that much time. If you're on differing channels, but still interfering, aka adjacent channel interference, then those messages may not be understood, causing a lot more collisions. Collisions being when two radios transmit at the same time and the channel needs to clear and everyone backs off, and you try again (usually happening on the order of milliseconds, and possibly several times per second). Collisions will negatively impact your performance more than the channel simply being busy. The protocol in use for wireless collision avoidance is CSMA/CA or carrier sense multi access with collision avoidance, which is an amended version of CSMA/CD (collision detection) used in half duplex wired communication.
How's that for a "short" answer?
For channel conditions, I'm looking at walls, building materials, open air distances, appliances, furniture... Anything that may attenuate, reflect, refract, or otherwise degrade signal strength whenever I start to assess an area for wireless. This is important so I know how many access points I need and how close together they need to be to overcome the obstacles placed in the environment. Once I have a rough idea of how many access points I need and how close together they should be, my next consideration is the expected client density and the objectives of the network. Something made for a busy stadium will have more access points than something made for a local cafe. If I'm doing a large number of access points my focus will be on maximizing how many clients can be connected, and driving that number as far down per access point/radio, as possible. Fewer people on a channel means more free airtime for their traffic, which equates to faster speeds. I'd be looking at using most of the 5ghz spectrum on the smallest channel width and have each radio be on its lowest power setting. You'll have clients moving between access points a lot, but you won't end up with more than a couple dozen per radio. I'd look into directional antennas, to minimize the broadcast range so I can reuse channels closer together. In such a high density space I would want to have some kind of Wi-Fi blocking or attenuation tech installed in the exterior of the building to prevent outside signals from coming in and inside signals from going out. Both for security and control over the airspace. Fewer things to interfere with; you only have to worry about what's inside that perimeter. Then it's a matter of setting up the channels for use in accordance with local laws, and letting the system handle channel assignment. With a huge number of access points, manually setting the channels is impractical. So everything I've said about it until now isn't even for channel selection, it's all things that support channel selection.
For small networks, especially in high density scenarios where the density is due to neighbors, whether that's commercial neighbors in a plaza or mall, or residential neighbors if you're in a suburb, an apartment, or a condo; for this, you want to pay careful attention to not only what other networks are around, checking from multiple points not only inside but outside of the premise as well, but what channels they're on and what their relative signal strength is. If signal strength is low then not a lot to think about. Avoid the channel if you can, but if you can't, there are worse selections. I'm also looking at the attenuation obstacles here, environments with large obstacles will benefit from lower band channels, either 2.4ghz or UNII 1 for 5ghz, and environments with a lot of radios on the 5ghz spectrum, may benefit from enabling the UNII 2 DFS channels (dynamic frequency selection). A lot of cheaper gear can't operate in the UNII 2 DFS space because they haven't bothered to implement DFS, which is a legal requirement for anything operating in that band. So the guys in the apartment next door that are using an off the shelf, cheapo router on sale from best buy probably won't have the ability to even select those channels for use, and you'll be free to use them with little to no interference... Unless the DFS triggers that is... For less dense areas I want to tend towards UNII 1 and 3 for stability, and only have enough 2.4ghz to cover the area. 20 MHz wide channels on 2.4ghz, 40 wide on 5/6Ghz. Should net about 400mbps or so per radio, and unless you have gigabit + Internet, with everything on Wi-Fi, some remarkably clear airspace, and only a single access point, going to 80mhz channel width is usually unhelpful. I'm looking at not only the channels with low/no occupancy, but I also want to look at how busy those channels are, but this aspect usually requires monitoring over a duration of time, with specialized hardware. I would choose to overlap with a dormant network with a stronger signal, than overlap with a network that is much weaker in signal strength, but very busy all the time. I also prefer channels 1/6 on 2.4 GHz because channel 11 is near the upper limit of 2.4ghz, and just above that limit is the frequency used by microwave ovens. If any microwave ovens don't have perfect shielding and you're on channel 11, you're going to have a bad time. In environments with more than one access point on 2.4ghz, I don't worry too much about it since any affected client can hop to another access point when interference ramps up.
There's more but my brain is tired today.
I wired my house with cat6 when I moved in. The overall setup looks like 10G fiber to the house -> 2.5G capable router -> 2.5G capable NAS running *arr stack. Also off the router is a single cat6 run downstairs -> 8 port 1G unmanaged switch, which is connected to my desktop, work dock, parters dock, TV, and backhaul run to the back of house wifi extender. The desktop, both docks and wifi extender are 2.5G capable. The TV is 100M. This has been extremely reliable. I plan on upgrading the switch to a 10g capable one at some point, and then the router. Since the switch is unmanaged, is there a good way to know when it is the limiting factor and I should update it?
What's the pros & cons of a managed vs unmanaged switch? Or of just running multiple cables out of the router? (Assuming your router has sufficient ports.)
My router only has four downstream ports, and due to the layout of my house I only want to run one cable from the router to my home office anyway. If it had enough ports and the house was laid out differently I wouldn’t have bothered with the switch.
Unmanaged switches are usually quite a bit cheaper and just work. You plug everything in and that’s it. Managed switches need configuring and cost more. I paid $25 for my 8 port 10/100/1000 switch, while the managed version is about $120. With a managed switch you can do things like turn individual ports on and off, traffic limit and monitor per port, and other fancy networking things that I’ve never bothered with.
Ah that's interesting. Thanks!
What does 10/100/1000 mean?
That’s that speed the ports are capable of. 10/100/1000 megabits per second. Most things with an Ethernet port nowadays are 10/100/1000 capable, and 2.5Gb is becoming reasonably common.
Weirdly, Roku and other smart TVs are often only 100Mb capable since 4k streaming only requires about 60Mb and if you are squeezing pennies a 1Gb port is a bit more expensive.
10Gb is just starting to get available for high end consumer devices.
Thanks a lot for sharing you experience! I recently saw some people I follow on youtube talk about fibre as an alternative for ethernet cables, do you have an any experience with that?
Alternative? Sure. Though why?
If ethernet works, you're just using a more expensive option to go with fiber.
Unless you need something unique about fiber, like distance (which can still be dubious for consumer grade hardware), or a non-electrical based signal (dubious requirement in most cases), then you're just throwing money at being able to say you use fiber.
Additionally, fiber is more fragile than a copper cable. One bad hit with a vacuum cleaner and it's toast
Yes. Fiber is great but extremely nuanced. SMF, MMF, UPC, APC, OM3, OM4, OS2.... All different parts of just the cabling... Not to mention the connectors, LC, SC.... You get the idea.
Everyone I tend to talk to about it seem to think multi-mode is cheaper, and it can be, but in my experience, single mode is usually the better choice and usually not much of a price uplift if you're buying from a good company. Look at FS.com and do some comparison shopping against them. They make some high quality stuff, and it's at pretty incredible pricing for what you get, but the equipment can add up fast.
Multi mode can only really carry one connection per fiber and usually needs to be duplexed (two strands per link) while single mode can leverage WDM to carry multiple independent signals on different wavelengths. This can be leveraged for bi-directional single strand links, multiple links that are aggregated into a single connection in hardware (this is how 40Gbit works, it's actually 4x10G connections on different wavelengths)....
It's still more costly and requires more specialized equipment and training to work with, compared to copper Ethernet, so it's pretty uncommon to see in residential or home networks.
YMMV. Good luck.
I feel like fiber only makes sense for long runs or extremely high bandwidth needs. For a typical home network, I don't see any benefits for fiber over ethernet.
The elevator pitch is wonderful and I'm glad to be following your recommendations already. Wired everything is not practical for me without drilling through the floor, so a mesh router with dedicated backhaul and a wired connection to the downstairs node is working like a charm.
I've been switching a lot of my devices to ESP-NOW instead of WiFi so that they can just fart out their data to anyone who can hear it and then go back to sleep, no connecting or handshaking or authenticating or overhead. Should clear up my wifi network I think.
If I'm not mistaken, they still use 2.4 GHz, which is also used by wifi, Bluetooth, ZigBee, a bunch of other stuff.... Microwave ovens.....
And anything operating on a frequency, regardless of protocol, will interfere with eachother. I think the main benefit for you would be the brief amount of active time, could reduce the airtime being used by the devices.
I hope it works out for you and your wifi works excellently. Just be aware that it could still interfere. Use 5ghz when possible.