How do I block someone from using my WiFi?
Hi, everyone.
Leo Notenboom here for AskLeo.com. Let's get right to this question.
It's a common one.
"If I have a WiFi user blocked from using my WiFi, how is it possible
that they are still able to be active on my WiFi?"
To put it bluntly, if they're active on your WiFi, you haven't blocked them.
Whatever you think you did did not prevent them from accessing your WiFi network.
I'm not sure what it is that's telling you they're active on your WiFi,
but assuming it's accurate, they're not blocked, period.
So how do you do this?
How do you block someone from using your WiFi?
It's a common issue and an important one,
especially in what I'll call dense housing situations where you can fire up your
laptop and see dozens, if not hundreds of WiFi access points out there.
Somebody could see yours.
What prevents them from connecting up?
Well, there are ways, some that work, some that claim to work but don't really,
and others that just aren't necessarily worth the effort.
First, I have to start with a caveat about your router.
I can't, unfortunately show you step by step, exactly what to do here.
The problem is that the steps will be different for every different router
manufacturer, every different router model.
The bottom line is that you'll probably end up accessing your router's
administrative interface and changing some of the settings we're talking about here.
But exactly how to do that, you'll have to refer to your router
manufacturer's documentation or website for the steps you'll need to take.
The number one most important thing
to protect your WiFi connection, use a password.
By that I mean make sure that the WiFi access point is configured to require
a password using either WPA2 or WPA3 encryption.
The issue here is that only people
who have the password will be able to connect to your WiFi.
That's it. That's the whole point.
Actually, that's not the whole point, but it's the point for this discussion.
If you've got a password protected access point and you don't give someone
the password, they can't access your access point.
Only those people you've authorized by giving them the password can do.
So.
Now, along those same lines, one of the things you should also do if
this turns out to be important is disable any guest WiFi.
Guest WiFi is, by its very definition, an open hotspot that anybody can connect to.
It's intended for guests.
Someone comes to your house and they want
to use your WiFi, but you don't want to give them the password.
Great for that scenario, but in the scenario we're talking about
here, it actually allows someone to use your WiFi.
Now, to be clear, it's a separate network.
When guest networking is available,
it's a separate network, so they are not on the same network you
are they aren't able to connect to, for example, your machines but they can
still use your internet connection by using and connecting to this open WiFi
hotspot that you have enabled at your router.
If your router supports this feature, not all do.
But if your router or access point
supports this feature and it matters, turn it off that way.
Again, only people who have the password
to your protected access point can connect.
Now, one of the pieces of pushback that I often get is Mac address filtering.
In other words, many routers have the ability to restrict
access to the network based on Mac addresses.
A Mac address is supposed to be a unique
number for every WiFi device on the planet.
To be honest, it includes actually all networking devices.
But we're talking about WiFi here.
So the WiFi in my phone should present
a different Mac address than the WiFi in my wife's phone or from my computer or
from any of the other WiFi enabled devices here in my home.
By recording the Mac address and then configuring the router to only accept
connections from devices whose Mac addresses are listed.
In theory, restrict access.
In practice, not so much.
There are two very big problems.
One is while Mac addresses are supposed
to be unique in practice, it turns out that sometimes they aren't.
Sometimes you can have multiple devices with the same Mac address.
It can cause other problems.
It's not supposed to happen, but it can.
The other is that Mac addresses can be changed.
For example, I think on my phone and I
know for windows I can change the Mac address that I appear as.
That doesn't sound like a big deal
until you realize that as part of the WiFi protocol, the Mac address of the devices
that are connected is transmitted in the clear.
So if someone were motivated enough to try and connect to your network and you have
Mac address filtering turned on, all they would have to do is monitor your network.
Look for a Mac address on a connection that appears to be allowed to connect,
set their device to that Mac address and then they can connect.
So as you can see, Mac address filtering totally not worth it.
I strongly recommend against it.
It's an administrative headache and honestly, it just isn't all that secure.
By far the number one thing you want to do
turn on WPA two or WPA three, use a strong, unique password and then
only give that password to the people you want to allow on your network.
Hope that was helpful. For updates.
For related links, for comments and more, visit askleo.com/142290. I'm Leo Notenboom
and this is askleo.com. Thanks for watching.