-: VoIP or Voice Over IP. 2 2
Now, Voice Over IP is a system 3 3
that digitizes your voice traffic 4 4
so it can be treated like any other data on the network. 5 5
You can do this by connecting it 6 6
to what's known as an ATA device, 7 7
which essentially is going to convert your analog voice 8 8
to something digital that you can use 9 9
and push over the network. 10 10
So if you've already used Vonage 11 11
and you had that physical device 12 12
that you plugged your phone into 13 13
and then connected that to your network, 14 14
that is an ATA device. 15 15
Now, you can use a fully digital environment as well. 16 16
Something like Skype or Cisco phone 17 17
that's connected over RJ45 or Cat5 cables 18 18
and they use the power of Ethernet to go back 19 19
to a call manager to make your phone calls. 20 20
Either way, we're going to talk about both 21 21
of these architectures a little bit more in this lesson. 22 22
Now, when you're dealing with VoIP, 23 23
it uses a protocol known as SIP, 24 24
the Session Initiation Protocol. 25 25
This is used to set up, maintain, 26 26
and tear down each one of those calls 27 27
and they give you that dial tone and maintain consistency. 28 28
Now, VoIP is really popular because it can save your company 29 29
a lot of money and provide enhanced services 30 30
over a traditional phone system. 31 31
When you talk about a traditional phone system, 32 32
you'll usually hear this referred to as a PBX, 33 33
which is a Private Branch Exchange, 34 34
or you may even hear it called POTS, 35 35
which is the Plain Old Telephone System. 36 36
Now, the reason you get caller ID automatically, 37 37
and then you can change names 38 38
and you can even do video over it, 39 39
it's all because you're using VoIP, 40 40
which is a digital service. 41 41
There are all sorts of things that you can do 42 42
with a great VoIP solution that you just can't do 43 43
on a private branch exchange or PBX. 44 44
So, how does VoIP actually work? 45 45
Well, you can run it inside a desktop computer 46 46
in your browser, like using Google Voice, 47 47
or you can use it with a handset, 48 48
or you can see an IP phone that is dedicated 49 49
like you see here on the screen. 50 50
These are all different ways that you can use VoIP. 51 51
Now, if I'm trying to talk to you 52 52
from a digital saying like, Google Voice or Skype, 53 53
and I want talk to your regular analog phone. 54 54
Well, we're going to have to make some kind 55 55
of transition between my digital world 56 56
and your analog phone, right? 57 57
So, how can we do that? 58 58
Well, when I pick up the phone, an IP phone, 59 59
it does a session initiation protocol 60 60
down to what's called a Call Agent. 61 61
That call agent then sets up the call through a router 62 62
and it goes up and connects to another router or a gateway. 63 63
That router or gateway is going to be tied to a PBX, 64 64
a private branch exchange 65 65
and this is going to initiate the call and that is going to create 66 66
this session initiation protocol that we're using. 67 67
And once that protocol is connected, 68 68
we can then use RTP, the real-time protocol 69 69
to actually pass the voice traffic during that session. 70 70
Now, when we go from the IP phone, through the router, 71 71
to the other router, and then to the PBX to make the call, 72 72
that then goes into the analog system 73 73
of the plain old telephone system. 74 74
Now, if all of that is really confusing, 75 75
don't worry too much about it because for the exam, 76 76
you don't need to know how this typology works, 77 77
except to know that VoIP is used to set up, 78 78
maintain and terminate the call using SIP, 79 79
the session initiation protocol. 80 80
And once that call is set up and being maintained, 81 81
the actual voice traffic goes through 82 82
the real-time protocol or RTP. 83 83
Now, next we have those PBX's and we can also create 84 84
a virtual private branch exchange. 85 85
Now, how do these relate to VoIP? 86 86
Well, this allows you to have the ability 87 87
to outsource your telephone system, 88 88
because everything now is just ones and zeros. 89 89
There's no reason that I can't just route this over to India 90 90
and have them handle my PBX for me 91 91
or some other cloud provider. 92 92
Now, this is going to use VoIP to send 93 93
all of your data to the provider, 94 94
and they're going to connect it to whatever telephone system 95 95
you need to use, whether that's US-based or overseas. 96 96
The benefit of this is that you can have this virtual PBX 97 97
that provide your voicemail, your caller ID, 98 98
your messaging systems, and everything else for you. 99 99
All you need to do is get and pay 100 100
for that standard dial tone and then you're in business 101 101
and you can start making phone calls all day long 102 102
at a really inexpensive rate.