-: In the last lesson, 2 2
we talked specifically about the way that we share data, 3 3
whether we're going to use a client server model 4 4
or a peer to peer model, 5 5
but we really didn't talk about the distance 6 6
that we could share it across. 7 7
And that's what we're going to focus on in this lesson. 8 8
So when we talk about network geography, 9 9
we're going to start with our smallest networks, 10 10
and work our way out to our largest networks. 11 11
The smallest one we're going to cover 12 12
is known as a personal area network, or PAN. 13 13
It's the smallest type of wired 14 14
or wireless network we can use, 15 15
and it usually covers about 10 feet or less. 16 16
So about a couple of meters of distance. 17 17
Now, some examples of personal area networks 18 18
would be things like Bluetooth and USB. 19 19
Bluetooth is a great example of one. 20 20
It operates at about 10 feet or three meters. 21 21
And if you have your phone in your pocket 22 22
and you get in your car, 23 23
and it starts transmitting music from your phone 24 24
wirelessly to your radio in your car, 25 25
that's only about three or four feet away, right? 26 26
This is an example of a personal area network, 27 27
because you have a connection 28 28
between your car stereo or radio, with your cell phone. 29 29
Now, what about your USB connections? 30 30
Well, those can be personal area networks too. 31 31
If I take a USB hard drive and I connect it to my laptop, 32 32
that's actually a serial connection, 33 33
and it's considered a network. 34 34
It's actually going to be a personal area network. 35 35
If you have an older standard, like FireWire 36 36
for your video cameras or a webcam, then you plug it in, 37 37
these would also be considered a personal area network. 38 38
Now, the way I like to think about this 39 39
is if I put my arms out to my side and I spin into a circle, 40 40
anything I can touch, 41 41
that's about my personal area network distance, 42 42
something around there, or maybe a little bit more. 43 43
Now, the next one we have is we get to a larger network 44 44
is called a LAN. 45 45
This is a local area network. 46 46
If you worked in an office building, 47 47
you probably had a LAN at work. 48 48
It connects components in a limited distance, 49 49
generally up to about 100 meters or 300 feet. 50 50
Each segment can only go about 100 meters 51 51
if you're using CAT 5 cabling. 52 52
But if you're going to use fiber optic cabling, 53 53
you can actually go further. 54 54
We'll talk about distance limitations 55 55
when we get to the ethernet fundamental section. 56 56
But for right now, when you think about a LAN, 57 57
think about it being a small office, 58 58
or one floor of an office building. 59 59
Now, your networks can be consisting 60 60
of either wifi or ethernet, 61 61
depending on how you want to set them up. 62 62
If you're using ethernet, 63 63
you're going to be using the IEEE 802.3 standard. 64 64
Now, if you're using wifi, 65 65
you're going to be using the IEEE 802.11 standard. 66 66
We'll talk specifically about these standards 67 67
in a future lesson, 68 68
as we dig deeper into the protocols and standards. 69 69
As you're going through the course, 70 70
anytime I mention a standard like 802.11 or 802.3, 71 71
you should write that down with a word next to it 72 72
that reminds you what that standard is used for. 73 73
So in my notes, I'd have 802.11, wifi, 802.3, ethernet, 74 74
something like that. 75 75
This will help you out a lot on the exam 76 76
if you have that cheat sheet at the end, 77 77
that you can study right before the exam. 78 78
Now, what are some examples of a LAN? 79 79
Well, the internal wired or wireless network 80 80
in your office building or in your school, 81 81
or in your classroom, 82 82
these are all local area network connections. 83 83
In fact, if you're sitting at home right now, 84 84
watching this video, 85 85
you're sitting on your local area network inside your house. 86 86
Making a connection between your devices, your printers, 87 87
your other laptops, your desktops 88 88
that are all inside of your house is part of the LAN. 89 89
Now, the next one we want to talk about 90 90
is going to be called a campus area network or CAN. 91 91
Now a campus area network is a building centric LAN, 92 92
that's spread across numerous buildings in a certain area. 93 93
So if you're at a college or a business park 94 94
or an industrial park, 95 95
and you have three or four different buildings, 96 96
they may all be linked together 97 97
in what's called a campus area network. 98 98
This can cover several miles, 99 99
and across many different buildings. 100 100
For example, I teach at several different colleges, 101 101
and each of those colleges has a campus area network 102 102
that spans the entire university. 103 103
And so no matter which building you're in, 104 104
each building has its own LAN, 105 105
local area network that you connect to. 106 106
But then those LANs are connected together 107 107
to form this campus area network. 108 108
Now, examples of this, again, 109 109
are going to be things like college campuses, 110 110
business parks, and military bases. 111 111
All of these form what is known 112 112
as the campus area network or CAN. 113 113
So up to this point, we covered our personal area network, 114 114
the small space around us. 115 115
We covered the LAN, 116 116
usually the area of our house or our apartment. 117 117
And then we covered our campus area network, 118 118
where we connect a couple of buildings together 119 119
that are within a couple of miles. 120 120
The next one goes even further out, 121 121
and we're going to talk about it, it's called a MAN. 122 122
A MAN is a metropolitan area network. 123 123
This is going to connect locations 124 124
that are scattered across the entire city. 125 125
This is larger than a campus area network, 126 126
but it is smaller than a global wide area network. 127 127
And so this can cover an area up to about 25 miles 128 128
or maybe even a little bit bigger, 129 129
depending on the size of your city. 130 130
So let me go back to my example. 131 131
One of the colleges I teach for is a community college. 132 132
They actually have six different campuses 133 133
spread out across our city. 134 134
Each of those campuses has a campus area network, 135 135
but each of those campus area networks 136 136
are also connected together 137 137
to form a metropolitan area network. 138 138
So all of our campuses are in one large university network. 139 139
Other examples of this 140 140
might be if you look at your city's department, 141 141
like the department of motor vehicles, 142 142
or the police department. 143 143
They may have lots of locations dotted across your cities. 144 144
And they're all connected together to form one network. 145 145
These are some great examples of what a MAN might look like. 146 146
And this brings us to our last one, our biggest network, 147 147
which is known as the wide area network, or WAN. 148 148
Now a wide area network 149 149
connects geographically disparate internal networks. 150 150
So this can consist of lease lines 151 151
or virtual private networks 152 152
that are tunneled over the internet. 153 153
Now, if you don't know what those two terms are, 154 154
don't worry about that right now. 155 155
We're going to go into both of them later on in the course 156 156
in a lot of depth. 157 157
So for right now, I want you to focus on the fact 158 158
that a WAN covers a large geographic area. 159 159
This may be across your state, across your country, 160 160
or even across the world. 161 161
For example, we actually look at the internet as a WAN. 162 162
It is a wide area network. 163 163
In fact, it is the largest wide area network available. 164 164
So if I'm sitting in my office, and I'm recording this, 165 165
and I'm going to upload it to a file server 166 166
that you're going to access from your home, 167 167
wherever you are in the world, well, 168 168
that's going to happen over a wide area network connection. 169 169
Now, another important thing to think about 170 170
when we talk about a wide network connection, 171 171
is the fact that they don't always have to be public 172 172
like the internet is. 173 173
In fact, let's take an example of a company 174 174
that has an office in New York, and an office in California. 175 175
Now each of those two locations 176 176
has their own local area networks, 177 177
but if we wanted to connect them together 178 178
over a private intranet, 179 179
we could do that using a wide area network connection, 180 180
because we're taking this very large network, 181 181
going across the entire country, and connecting it together. 182 182
So we have these two local area networks, 183 183
but they're still tied over this larger WAN link. 184 184
A good example of this 185 185
is the Government of the United States. 186 186
They have offices all over the country, 187 187
in fact, all 50 states, spanning 3 or 4,000 miles, right? 188 188
All of those can be connected 189 189
through a private wide area network connection, 190 190
so that they have a wide area network 191 191
that is made up of all of these smaller networks. 192 192
So when we look at network geography, 193 193
I want you to remember the distance involved. 194 194
So as we start thinking about this, 195 195
let's look at this diagram. 196 196
We have our smallest network, the personal area network, 197 197
and then we move out, and we get to our local area network. 198 198
And then we go even further. 199 199
And we start getting a couple of buildings 200 200
with our campus area network. 201 201
And then we connect a couple of those buildings together 202 202
across the city, 203 203
and that becomes a metropolitan area network. 204 204
And then finally, we go across the state, the country, 205 205
or even the world with our wide area network. 206 206
So when it comes down to it, 207 207
if you can remember this one slide, 208 208
and these distances that we're talking about, 209 209
smallest to largest and what these networks stack up, 210 210
you're going to be able to answer any question you get 211 211
as far as PANs LANs, CANs, MANs and WANs on the exam, 212 212
because you'll know how far they can go, 213 213
and what type of networks that they're using to do it.