# Interference and Frequencies (part 2) - Gigahertz Frequencies

Video Activity

Gigahertz Frequencies This lesson discusses 2.4 the gigahertz frequency; which has 14 channels. Only channels 1-11 can be used in the USA as the remaining channels are closed off for government use. Typically, we use 1, 6 or 11 as channels need separations between them to be the most efficient. Participants also learn about the 5 gigahertz frequenc...

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Time
31 hours 29 minutes
Difficulty
Beginner
CEU/CPE
30
Video Description

Gigahertz Frequencies This lesson discusses 2.4 the gigahertz frequency; which has 14 channels. Only channels 1-11 can be used in the USA as the remaining channels are closed off for government use. Typically, we use 1, 6 or 11 as channels need separations between them to be the most efficient. Participants also learn about the 5 gigahertz frequency, which is more expansive and has more channels. Some of these channel have restrictions and special training is needed to set them up.

Video Transcription
00:04
So let's talk about our 2.4 gigahertz frequency
00:08
now are 2.4 gigahertz. Frequency
00:11
has 14 channels, but here in the United States, we can only use channels one through 11 because channels 13 and 14 are closed. Our channels 12 13 and 14 are closed off for government use
00:27
Channel 14 of the 2.4 gigahertz range. So 2.4, whatever is Channel 14 is used by the government for certain purposes, certain military applications and they don't want any interference over on that channel.
00:42
So they give themselves a channel 12 and 13 buffer away from channel 14
00:48
so they don't have that interference are different channels. So our channel 12 and six will display will up. We'll need two channels of separation between their adjoining channels.
01:00
So
01:02
if we draw out our chart here and we have channels one,
01:06
234567
01:11
89
01:14
10
01:15
11 We're gonna stop with 11 because we here in the United States, we can't use past that certain countries. You can use more than that, though, so he would just depend on what country you're in.
01:25
Um,
01:26
we can typically will want to use channels one,
01:30
six
01:32
or 11.
01:34
And again, this is because our channels need
01:38
two segments of separation on either side.
01:42
So our Channel one is no big deal because,
01:46
well, we go that way.
01:49
And then our channel on the other direction
01:53
covers channels two and three.
01:59
So that's our
02:00
That's what we cover when we're using our Channel one on our 2.4 gigahertz frequency. Now, remember our 2.4
02:08
gigahertz band? This is our 2.4 gigahertz band, and these are just some additional numbers that we tack on to the 2.4 frequency. But rather than saying, Oh, I use the frequency of 2.412 you should be on 2.437 You make it a little bit easier by just calling them channels
02:28
in breaking them up into one through 11.
02:30
But for those of you that are interested
02:32
and like this kind of stuff,
02:36
which I do as you can tell, each of these bands are actually 22 megahertz,
02:43
actually 22 megahertz wide. So, uh,
02:47
this Channel one would be 2.412
02:52
and it would cover
02:53
22 22 total half in one direction happened the other, so we would cover 11 in one direction. So that's why it's 2.412
03:05
It would cover back to 2.41
03:07
and then it would cover up too.
03:10
2.4 to 3.
03:15
So anyway,
03:15
next we have our Channel six, which is 2.437 This is all information that you don't need to know for the exam. So I'm gonna stop talking about it so we don't get confused.
03:25
But it's good to know and get to understand for how our channels work.
03:30
Next, we have our Channel six, which again is going to use two channels in each direction. It was going to use channels four and five
03:38
and then channel seven and eight
03:43
and see, we leave ourselves a gap here, a buffer between between three and four
03:47
and then channels 11. It's gonna cover over two channels nine and 10
03:53
and then also cover over to 12 and 13
03:57
and then for 12 13 and 14 we can't use because they can enter cause interference on that Channel 14. So we do not use channels, do not use channels 12
04:09
13
04:10
in 14 most times buying a router in the United States. You even you can't even set your router to use those channels 12 13 or 14. They're locked down, but channels one through 11 are available, and we want to set up our different channels to be on those frequencies.
04:26
So
04:27
again are different. Wireless are different wireless routers when they ought to negotiate what frequency they're going to use, what channel they're going to you. Well, we set up our wireless router and indicate what frequency is going to use, what overall frequency band it'll use.
04:43
And then you automate it. Will auto negotiate what sub channels it's going to use within that band?
04:47
Typically.
04:48
But if we pull out, if we're noticing a lot of interference and we want to make sure that our channel isn't functioning, we don't we're using the wrong channel. We can pull up wireless software that will actually show us a and display tow us where our channels are and what channels were using compared to
05:08
other people and other wireless access points around us.
05:11
So if we pull up A. If we pull up our wireless
05:16
software
05:18
and
05:20
our frequency we're using Channel six. So it's going over channels for
05:27
and channels eight. And then our neighbor number one is using Channel One.
05:32
And then our neighbor number two is using Channel 11.
05:38
Then we're okay because we are really having any frequency from those two neighbors.
05:42
But if we noticed that
05:45
we're using the same channel is our neighbour. Maybe some auto negotiation failed.
05:49
We're using the same channel,
05:51
and Channel six is open. We can manually set our router to move over to Channel six.
05:59
Or if we noticed that maybe our neighbor is they set up their router incorrectly somehow. Or they did some special manual configuration and they're not on Channel One down on channel two.
06:12
So they're covering back and there can't covering up the Channel five and we're on Channel six.
06:18
We're covering back to Channel four
06:23
and are sorry that they're covering up to there on Channel three.
06:27
So they're covering up to Channel five and back to Channel one,
06:31
and we have this interference here. Now
06:35
we have this red zone
06:38
of interference.
06:40
Now what's better?
06:43
Well, the best solution would be to knock on a neighbor's door and asked them to move their channel. Not really. Unless you know your neighbor very, very well. And you're comfortable with saying that you probably don't want to address what wireless channel their routers on, or if so, you may want to have them watch this video and then they'll understand.
06:59
But rather than go knocking on people's doors and asking to check their wireless router settings,
07:04
we may we have two options.
07:08
Do we want the interference of crossing over a channel?
07:13
Do we want that little bit of overlap,
07:15
or would we rather just move on to the exact same channel that they're on? We rather just say I forget it rather than having a little bit of interfaith interference. I'm going to be on the same channel is them? I'm gonna move on to a neighbor number two's channel. I'm gonna move on to Channel 11 or
07:30
rather, the neighbor that has their wildest setting screwed up. I'm gonna move on to Channel three with that neighbor.
07:36
It's better to have our wireless channels exactly the same been overlapping,
07:42
and here's the reason
07:44
I think of it like being at a party
07:46
and you're trying to and you're trying to talk to someone you're trying to talk to your friend and then someone else is also trying to talk to a different friend.
07:55
Well, if you're having a conversation with someone and ah, conversation is going on right beside you,
08:01
it's really hard to focus sometimes on that conversation, especially if your volumes are kind of equal. So if you're if you're having a conversation and then they're having that side conversation and every once in a while you start trying to listen over. But you're like No, no, no, wait, I'm not talking to that person. I'm talking to this person. It maybe it's difficult to have a conversation. You're gonna have a lot of
08:20
trouble speaking and listening to the other person and listening to what they're saying.
08:24
But if, rather than having to separate conversations, you know that of a group of people. So you just say, Come here, come here, come here. We're having to side conversations. Let's just have one big conversation. You can talk to this person, but then while you're talking will be quiet and then we'll talk and you'll be quiet. That's what
08:41
over that's what completely the same channels would be
08:46
rather than having those two side conversations where you're half listening to someone else you're saying, Okay,
08:52
I'm gonna talk to this person and then you talk and then I'm gonna talk, and then you talk, So that's how are exactly the same channels are gonna be. Our wireless router says I'm gonna wait until you stop talking. Then I'm gonna talk to my client and then you talk and then I talk. There's still interference, but it's not. It's not as bad.
09:09
So
09:11
knowing our channels, knowing how our channels work and knowing the difference between our overlaps is critically important, especially for setting up our own wireless access points. This is why we said earlier that if you are setting up multiple wireless access points that overlap where their range is, where their signals push out,
09:30
you need to make sure that
09:31
your wireless access points on Lee overlap if their channels 16 or 11
09:37
and if you have to wireless access points on channel 11 they're signals. Better not cross paths. You wanna put them as far away that your network allows to keep their signals from overlapping.
09:50
So that's all about our 2.4 gigahertz range.
09:54
Now our five bigger hoods range are five gigahertz. Band
09:58
does the same thing. It has additional point, whatever underneath of it.
10:03
But you can see, because our five Giger of 2.4 gigahertz band on Lee allows us to 0.4 to 2.5,
10:13
where we have a lot less. If we are working on the five gigahertz ban and we have five gigahertz to six gigahertz,
10:20
that's a lot more channels toe have potential information on ah, lot more. So we're actually not gonna actually list out every single channel here.
10:30
We're just surprising because of all the other in depth information we've gone into.
10:33
But this five gigahertz band is gonna have more channels, but there are some that have special restrictions and actually require specialized special training and special individuals to set them up.
10:46
That's because five gigahertz band some sub channels also run also can cause interference with some radar systems.
10:56
So we need to make sure that if we are setting up a five gigahertz router,
11:01
our router that pushes out on the five megahertz band will typically want to let that one auto negotiate or pick from some of the default channels. But in a large corporate environment or a large enterprise environment where they can pay to hire very, very specialized companies to come in and install these,
11:20
there's specialized equipment that they may use in order to tune these routers,
11:26
to tune this band to make sure that they're not causing additional interference. Or they're not breaking any federal regulations by causing any interference with any other devices.
11:35
That's our interference and our frequencies. Just remember that our two main frequencies are going to be our two main frequency bands are going to be 2.4 and five gigahertz Band are 2.4 gigahertz Band. We have channels one through 11 in the United States, which were allowed to use,
11:52
and our five gigahertz band has more channels, but a lot require specialized tuning.
11:56
Remember that our 2.4 gigahertz band is more crowded and thus may have Maur interference and pushes less data per radio wave.
12:05
But our 2.4 gigahertz band can also push out a longer range because of the way that it's wave is structured
12:09
are five gigahertz Band has Maur data per each radio wave, but it is more expensive tea, maybe more expensive to set up and to purchase a router, which functions under five gigahertz. And our five megahertz band is also shorter and has a shorter signal signal like that it can push out.
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