-: Network Basics. 2 2
So, when you think of a computer network, 3 3
what comes to mind? 4 4
Do you think of a router and switch? 5 5
Do you think of your wireless network at home 6 6
that you're accessing this video over? 7 7
Is it limited to just computers? 8 8
Is it limited to just the internet? 9 9
Is it limited to WiFi 10 10
or wired networks, like ethernet or fiber? 11 11
Well, no. 12 12
There are a lot of different types of networks out there, 13 13
and when it comes down to it, 14 14
the purpose of these networks is to make connections 15 15
between lots and lots of different types of machines. 16 16
For example, if you have an Apple Watch 17 17
or some kind of other smartwatch, 18 18
there's a connection between your watch and your smartphone, 19 19
and this happens over Bluetooth. 20 20
And guess what? 21 21
This a network. 22 22
It's actually called a PAN, a personal area network, 23 23
because of the small distance 24 24
between the phone and your watch. 25 25
Now there's also the typical WiFi network 26 26
that you're used to 27 27
when you connect your tablet to your wireless access point 28 28
at home. 29 29
And then, you connect out to the internet. 30 30
These are also networks. 31 31
Or maybe your desktop is connected to a hub, 32 32
and then connecting to a switch 33 33
that connects to a router 34 34
and then that connects to the internet. 35 35
All of these are parts and pieces of a network. 36 36
You see, there's a lot of different kinds of networks 37 37
out there 38 38
and these networks all have started to become converged 39 39
over time. 40 40
Now in the old days, 41 41
we had different networks for different purposes. 42 42
When I grew up, we had a telephone network 43 43
and all it did was allow us to pick up the phone 44 44
and make a phone call over an analog network. 45 45
And then, we had computer networks 46 46
and those were used to transmit data back and forth 47 47
over a digital network, 48 48
and these were separate things. 49 49
An analog phone network and the digital data network. 50 50
But over time, all of this merged and converged. 51 51
And now, we have often single networks 52 52
that do voice, video, and data, 53 53
and it's all traveling over the same network lines. 54 54
So these days when you pick up your smartphone, 55 55
it really doesn't care whether you're making a voice call, 56 56
sending out a text message, or you're surfing the internet 57 57
or watching a video. 58 58
All of this is going to use your data connection. 59 59
To the phone and the carrier, it's all created the same. 60 60
It's just ones and zeros going out over a digital network. 61 61
Now because of this convergence 62 62
and our reliance on our networks, 63 63
we expect a high availability in uptime 64 64
for all of our networks and devices. 65 65
As somebody who used to be an IT director 66 66
for a large organization, 67 67
I can tell you that our customers expect 100% uptime. 68 68
But honestly, that is just not realistic 69 69
because that means we would never have any downtime 70 70
and nothing would ever go wrong. 71 71
So instead, our promise 72 72
to our customers and business networks 73 73
was that we would have a 99.999% uptime. 74 74
Now this is what we call the 5 nines of availability. 75 75
That's a common networking term. 76 76
This isn't 100%, but it's pretty darn close 77 77
and pretty darn reliable. 78 78
So what does this equate to in real numbers in our network? 79 79
Well, it means that through the course of the year, 80 80
I'm only allowed to have five minutes of downtime. 81 81
That's it. 82 82
Five whole minutes each year for all the downtime required. 83 83
The rest of the year, all 365 days, 24 hours a day, 84 84
I have to be up and running 85 85
with my network and my devices all of the time. 86 86
And that's the challenge that we face 87 87
as network technicians and network administrators. 88 88
We've got to keep these networks up 89 89
and keep the data flowing. 90 90
So in this course, 91 91
that's exactly what we're going to teach you. 92 92
We're going to help make sure you understand 93 93
the fundamentals of networks 94 94
and how to troubleshoot thing when they break 95 95
because this is fundamental 96 96
to keeping our networks up and online. 97 97
Now once we have those networks up and running, 98 98
you may be wondering, 99 99
"What kind of things can we do with it?" 100 100
In other words, what kind of network traffic 101 101
can we expect to see within our converged networks? 102 102
Well, we have things like file sharing 103 103
and video chatting, like Skype and FaceTime. 104 104
We have surfing the web, 105 105
like going to Google and Facebook or diontraining.com. 106 106
There's social media like LinkedIn and Facebook and Twitter. 107 107
There's streaming videos, 108 108
like what you're watching right now 109 109
or going over to YouTube or Netflix. 110 110
There's emails, there's instant messages, 111 111
there's voice over IP with phone calls. 112 112
THere's lots and lots of different types of traffic 113 113
all going across our network 114 114
and there's new types of traffic 115 115
happening all the time, as well, 116 116
because new things are being designed 117 117
and added to our networks. 118 118
And we as network technicians and administrators 119 119
are going to be expected to support all of it. 120 120
Supporting all of this network traffic 121 121
is a huge struggle and a big challenge, 122 122
especially if you want to maintain 123 123
those 5 nines of availability. 124 124
That 99.999% uptime. 125 125
But, we're going to work through that 126 126
and all of the different challenges and how we overcome them 127 127
throughout the rest of this course. 128 128
So what are we going to cover in this section of the course? 129 129
Well, we're going to be focusing on network basics, 130 130
such as the different components of our network, 131 131
the resources in our networks, 132 132
the network geography we use to describe our networks, 133 133
the basics of wired and wireless network topologies; 134 134
and some of the newest types of network clients, 135 135
the Internet of Things. 136 136
We're going to spend most of our time here in Domain One, 137 137
networking fundamentals 138 138
specifically focusing on Objective 1.2, 139 139
which states that we must be able to explain 140 140
the characteristics of network topologies and network types. 141 141
We're also going to briefly cover a portion of Domain Two, 142 142
network implementations, 143 143
by discussing Objective 2.1 144 144
in our network components lesson, 145 145
as we compare and contrast various devices, their features, 146 146
and their appropriate placement on the network. 147 147
So let's dive into this section on Network Basics.