All About Wi-Fi

This is going to be a rather lengthy article covering some pretty technical aspects of wi-fi. As usual, I'll try to avoid using a lot of jargon and I'll define the jargon where I do use it.

In this article, I'll discuss how wi-fi works, why it's crappy so often, ways to make it better, security considerations, and other stuff.

Even non-geeks should get a pretty solid understanding of the ideas presented here in the ways that I describe things. I'm a king of analogies, if nothing else. 😁😁

To start, we'll discuss a little history. Regular readers of my articles know that I love to discuss the old days...

radio spectrum usage

Wi-Fi doesn't mean anything

If you're over about the age of 40 or so (as of this writing, 2020), then you may have had a home stereo, or "Hi-Fi" system and you know what Hi-Fi means.  For the rest of y'all raised on iPods and ear-buds, "Hi-Fi" means High Fidelity -- a high-quality component stereo system with good speakers that accurately reproduces recorded music.

Back in the 1990s, what is now the Wi-Fi Alliance needed a brand, a name, a term for the then-new local short-range wireless protocol to be used to access the internet from our computers, laptops usually. So they hired a branding company and they came up with "Wi-Fi". 

Problem is, "Wi-Fi" doesn't stand for anything -- it never did. 

Yes, one could argue the "Wi" means wireless and that fits pretty nicely. But then human nature needs to find a meaning for "Fi" as well. And that's where the "Wi-Fi" branding fails us. The term Wi-Fi was coined long enough ago that having a home stereo system, a Hi-Fi, was still fairly likely. And so, because nature abhors a vacuum, people just assumed the "Fi" meant "Fidelity". It didn't then and it doesn't now.

Although "Wi-Fi" itself doesn't stand for anything, it does represent something very specific. When we say "Wi-Fi", we are referring to a specific type of wireless protocol. This protocol is used to connect laptops, smart phones, tablets, and printers to a local, short-range (within a single building or residence), access-point that is connected to a hard-wired modem for accessing the internet.
 

This specificity is important. All smartphones and some tablets have two ways to access the internet -- cellular and wi-fi. Both ways are wireless, obviously, but only one is called "wi-fi". As it turns out, understanding that difference is pretty important.

HAM

I'm an amateur "HAM" radio operator. Another word that doesn't stand for anything. For those who don't know what that means: I hold a license from the FCC (a federal agency) that grants me the privilege to transmit powerful radio signals (voice , usually, but could be Morse code or even data these days) that can reach the other side of the world under the right circumstances. Having a HAM radio license (or "ticket" as we say) means I studied-for, passed several exams, and understand a number of laws about radio waves. Both laws of man and laws of physics.

A wi-fi router is just another radio transceiver, albeit highly specialized. So combined with my networking kung fu I've got a pretty good understanding of how wi-fi routers work and why they don't.

Save on your phone's data plan

I've visited many clients who did not know their smartphones could access their home wi-fi networks. Their laptops were connected to the wi-fi, but not their phones. Since the phone could access the internet (via cellular) then it didn't occur to these clients that anything else needed to be done, e.g. connecting to the home's wi-fi network. After all, the phone can get online, so what else is there to do, right?

Why is that a big deal? Because using cellular on your phone chips away at your monthly data allotment. If you enjoy data-intensive activities on your phone (watching videos, especially) but even sharing photos or streaming music, then you can easily hit your data allotment for the month and incur additional fees from your cellular carrier (Verizon, AT&T, etc.)

But if your phone is connected to a wi-fi network, then all downloaded data comes through the wi-fi instead. That means you aren't using your cellular data while you are at home. If you regularly exceed your cellular data plan allotment, there's a good chance you aren't connected to your home wi-fi while at home.

If you don't have a wi-fi at home, but you do have internet, then a wi-fi device can be easily added and there's no additional monthly expense. Just a one-time cost for the device itself. You could recoup that cost pretty quickly by not going over your cellular data plan.

Nosy Neighbors

It's critical that your wi-fi network has a password to prevent your neighbors from surfing on your signal. You don't want the neighbor across the back fence surfing for child porn on your internet connection! Wi-fi usually doesn't work well that far, but it may work well enough for your immediate neighbors to use. So lock it down using a password.

Guests and medicine cabinets

It's a bit of a trope that guests like to snoop through their host's medicine cabinet to see what private health issues they can suss out. Well, if you let your guests on your wi-fi network, they could possibly do the same thing if they are tech-savvy enough: Snooping around your network and possibly onto your computer. Or any malware that might be on their laptop could infiltrate your network!

How to avoid that? Some wi-fi routers have a "guest mode" that is designed expressly for your guests and visitors. The special mode allows the guest to reach the internet only. They are blocked from accessing any other device on your network. This way, your network remains secure both from snooping and possible malware infection. The guest mode has its own password so you can freely give it to your guest without disclosing your private wi-fi password.

Some routers don't have a guest mode. And even the ones that do, it's usually disabled by default. An I.T. geek like me can enable that for you by accessing the router's management console. I can even to that remotely! Or if your router lacks that feature, I can install one that does.

This is actually pretty important. If you have guests or visitors that want to access your network, it's really important that they use only an isolated guest network. Allowing guests on your private wi-fi network is akin to needle-sharing by junkies. Yes, it's that bad.

Radio Roadblocks

The high microwave frequencies (2.4 GHz and especially 5 GHz) used in wi-fi are easily absorbed by nearly everything. So, attenuation (weakening) of the radio waves by obstacles in your home or office is a problem. That means absorption by furniture, appliances, walls, floors (for a multi-level home), and even people and pets. Distance also plays a role. Getting a bigger, badder wi-fi router doesn't help, either. First of all, there are max legal power limits that manufacturers cannot exceed. But aside from that, higher power often decreases performance! More on that in a bit.

Other ways to reduce absorption is to place the wi-fi router as high as possible, such as the top of a tall cabinet.  I know, I know... How to possibly pull that stiff coax cable to the top of some cabinet in next room that's nowhere near a cable outlet. More on that down below as well!

 

But think about it. Everything in your home ultimately starts at the floor. The highest density of stuff occurs at ground level.  As your point of view rises farther above the floor the view becomes less obstructed. Higher up, near the ceiling, it's likely a much clearer shot all over the house except for the walls.

Shouting in a loud restaurant

Imagine yourself in a packed restaurant or bar (ok, pre-covid). How loud do you have to talk to be heard by the person next to you? If you start speaking louder to overcome the din around you, well, everyone else will do the same thing. Pretty soon it's deafeningly loud and no one can understand much of anything.

Wireless internet devices operate in a "collision domain". Say what? Unlike the restaurant mentioned above where everyone is loudly talking at once (and having a hard time understanding anything), wireless devices cannot do that. If two or more proximate wireless devices start transmitting on the same channel at the same time then a collision occurs and neither device is heard.

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Each colliding device then stops talking (transmitting) then waits for a random number of microseconds. The idea being that each device will choose a different random wait time so the likelihood that both will start retransmitting again at the exact same time is low. This works pretty well when there's only a few devices involved and traffic levels are low. (Traffic is data being transmitted)

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But what happens when there's a lot of wireless devices and some of them are bandwidth pigs? I'll spare you the math here, but as more devices come online and wi-fi traffic levels increase, the collision rate expands geometrically. At a certain point, the rate of retransmission swamps the channel capacity resulting in a dramatic drop off in throughput -- that noisy restaurant! Obviously not good.

Crowded Airspace

It's not unusual for (some) homes to have a dozen or more wireless devices when you consider all the gizmos available today. In additional to the usual laptops, phones, and TVs, we also have a plethora of mostly-pointless ("Internet of Things") wi-fi gizmos such as thermostats, baby monitors, door locks, ring cameras, and a wide range of appliances like wi-fi coffee makers, ovens, stoves,  dishwashers, clothes washers / dryers, refrigerators, and likely many more! And the same thing goes for all your neighbors as well.

 

Ever see one, two, half or a full dozen of your neighbor's wi-fi networks on your laptop or phone? Even though your wi-fi network and your neighbors' are separate and secure (that's what the wi-fi password does), they are still sharing the same radio channels. If you can see your neighbor's wi-fi router, then all his wireless gadgets are also within radio visibility as well. And vice-versa -- all of yours are within radio visibility to his network. Depending on channel availability and signal strength, that means your devices and his devices cannot both talk at once, even on their own separate, secured, and isolated networks!

If you live in close quarters with your neighbors, such as an apartment building or condo, or even single family homes that are packed in close together, then the effect above can be multiplied by far more than just two. It could be a dozens!

Now, factor in devices that are high-traffic like streaming video (Netflix, Youtube, etc.). Your streaming device could be receiving so much traffic that the rest of your network (including the offending device) is suffering as a result. Throwing in more power or buying higher speed bandwidth from your ISP isn't necessarily the answer, either. And due to radio visibility between nearby homes, your neighbors streaming TV could affect your network!

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And if all the foregoing wasn't bad enough, factor in devices that aren't intelligent and "wireless aware" like your microwave oven or some cordless phone models. Now throw in multi-path issues and signal absorption, etc. These are intrinsic problems with wireless devices.

Maybe you are wondering how your network can be secure if your wi-fi traffic can reach your neighbor's home? Or why several homes, each with their own network name and password cannot all use the same channel?

Think of a smallish room, bedroom-sized say. In my analogy, that room is like a wi-fi channel. Inside this room are two or three groups of people, maybe 3-4 persons per group. Each group speaks their own language that the other groups don't understand. If all the groups are talking at the same time then it may be difficult to focus on the others in your group because there's too much noise.

 

Now suppose the groups take turns with only one group speaking at a time. It's a lot easier to communicate now with others in your group without a lot of chatter from other the groups. And it doesn't matter that other groups are sharing the same room (channel) because they each speak a different language (password). This is how a limited resource can be visible-to and shared-by several parties yet still maintain privacy.

Another analogy is if everyone that shares an old-fashioned party line each spoke a different language. The nosy neighbors can listen in all they want but they won't understand anything. But what they cannot do is use the party line at the same time.

2.4 GHz vs. 5 GHz

The US has two main frequency bands* that are used by wi-fi routers, each with their pros and cons. Nearly all wi-fi routers sold today offer both bands. Here's a rundown of pros and cons of each.

2.4 GHz - Pros

  • Wider device support - Most printers and some IoT gadgets still only support 2.4 GHz. Not a big deal since printers and most IoT gadgets are fairly low traffic devices, except for that stupid video doorbell.

  • Better penetration of obstacles - Walls, furniture, appliances, and distance don't affect 2.4 GHz as much. Mind you, this same penetration advantage can work against you if your neighbor is on the same channel.

2.4 GHz - Cons

  • Inherently slower band even with no interference from other devices

  • Fewer channels resulting in more overlap which leads to collisions which means poorer performance

  • Far more crowded in any event. There's simply more devices on 2.4 GHz than 5 GHz (though that's changing)

  • Interference from certain cordless telephones, microwave ovens, and other non-friendly devices on this widely used band

5 GHz - Pros

  • Much faster when signal strength is decent, often a 10x improvement in speed

  • Less crowded though more people/devices are starting to use it

  • More channels available, resulting in less crowding per channel

  • Shorter range means less interference from other distant 5 GHz devices, like your neighbors

5 GHz - Cons

  • Most printers do not support 5 GHz. Some are starting to but it's not universal yet.

  • Shorter range can be a con, too, especially if you're in a fairly isolated area where neighbor interference isn't a concern.

5 GHz is more susceptible to attenuation from environmental obstacles. That's actually a pro in that it helps prevent interference from neighbors. It's a con when it limits connectivity in your own home. But on balance it's a pro because you can mitigate your own limited range issues by using additional access points or a mesh network. But you can't do much to limit interference caused by a neighbor.

Regarding printers being on 2.4 GHz and your other devices on 5 GHz: From a networking perspective, this matters not. Devices on these two bands and those that are hardwired can all communicate with each other, no sweat.

Clarifier:  5 GHz on wi-fi and 5G on a smartphone mean completely different things!

  • 5 GHz (wi-fi) refers to a frequency band (radio waves). Some wireless routers include "5G" on the wi-fi name to signify that it's 5 GHz. What an unfortunate use of that term since it needlessly conflates "5 GHz"  with "5G". Do not be confused by this.

  • 5G (smartphone) means "fifth generation", which is strictly a marketing term (no intrinsic technical meaning) referring to a newer class of high-speed cellular data that is barely just beginning to be deployed in the US and elsewhere.

* A band is a defined frequency range in which individual channels reside. e.g. Your car radio has AM and FM bands. Each of these two bands have lots of channels and behave differently, having their pros and cons. e.g. FM sounds better but AM can work farther at a given power.

The gold standard

The above should convince you that RFI (Radio Frequency Interference) is a thing. Hard wiring fixes that! Hard wiring always offers a superior connection and should be used whenever possible.

So what to do? There's several things to do here, each contributing to reducing wi-fi traffic. 

Ways to reduce wi-fi traffic:

  • Hard wire your streaming TV or player appliance like Roku or Apple TV. If you do nothing else, just removing a streaming device from the wireless ecosystem will help.

  • Hard wire all stationary computers including towers, AIOs (All In Ones), and even laptops while they're being used at their main location such as a desk.

  • Hard wire your printers that have an Ethernet port.

  • Hard ware all gaming consoles. This will reduce gaming lag as well.

  • Reduce or eliminate stupid IoT gadgets from your home. Aside from reducing the wireless footprint, you'll eliminate some security vulnerabilities as well. For more on IoT, see Internet of Things

  • And for all that is good and holy, please don't buy wireless security cameras! Install only hard wired cameras!

In short, reserve your precious wireless spectrum for smartphones and tablets.

Tearing down the walls

OK, I'm sold! But how do I hard wire my TV and main computer? Hardwire means an Ethernet cable from your router (there are ports on the back just for this) to your TV, main computer, whatever else. Yes, running cables is a PITA and may require some creative solutions. Or you could hire a cable monkey to do it. But I absolutely guarantee that you'll have a better streaming and internet browsing experience if you do this. And with fewer devices on your wireless network, those that remain wireless should perform better as well (depending on your neighbors).

For an office environment, it's an absolute no-brainer. Offices should be hardwired, period.

Other wireless issues

Maybe you don't have a ton of wireless stuff. But perhaps your home is large and you just want a decent signal for your phone or tablet everywhere in your home. There are solutions that can reliably blanket your home with a good signal. As I said higher up, wireless signals are attenuated by many things in your home -- appliances, furniture, walls, distance, and floors (for a multi-level home).

For larger homes, e.g. greater than 2,000 sq/ft, especially if all on one floor (large footprint), it can be difficult getting a decent wireless signal to all areas, no matter how powerful the wi-fi router. There are several ways to accomplish this.

Ways to improve wi-fi signal throughout your home:

  • Hardwiring additional wireless access points strategically located within your home.

  • Ethernet over power line transceivers, with optional additional wireless access points.

  • Wireless mesh system such as EERO, Orbi, Google Wifi, etc. These mesh systems aren't cheap, but they do work pretty well. I've installed quite a few of them. I prefer EERO.

The newest kid on the block are wireless "mesh" systems. A mesh system uses multiple nodes or pucks (three is common) strategically placed throughout your home. Each node is a wi-fi access point that provides a strong signal in that part of the home. The node relays wi-fi traffic back to the main node that's connected to the modem.

EERO was the first to introduce a consumer-oriented mesh system at retail. Then came competitors like Google WiFi, Orbi, Velop, Plume, and others. I've personally installed EERO, Orbi, and Google Wifi -- dozens of them. I've had the best experience with EERO.

The mesh nodes are also attractive to look at. Or at least they're not ugly. They're small, usually all white, have few or no markings, have no visible antennas, and is inoffensive on an end table or top of a cabinet.

Avoid the inexpensive ($30 or so?) "wireless repeaters" that plug directly into a wall outlet like a nightlight. These often have two short antennas attached. This type of repeater is not the same as a proper mesh system and are suboptimal because of how they repeat the signal. 

That's a wrap

OK, so we've covered a lot of topics here, all pretty technical. If you are having "internet problems" then there's a good chance your wireless setup is the cause. I can help diagnose that, remotely even.