the data instead of the packet switch network where it just uses the Internet.
So, that's just.
So, to get the circuit switch networks,
they would have to setup the physical telephone lines.
Sometimes you've seen them in movies where they have the long poles and
just runs across everywhere.
And then, sometimes you'll need to call someone in Europe,
you'll have to have an underwater giant cable, something like that.
>> And while traditional analog telephones still exist,
the public switched telephone network will as well.
Because even when using VoIP,
the VoIP signal eventually gets to a point where it needs to find the telephone.
>> Yeah, so all these were just the traditional landline phones, whatnot.
And since it's had so much time to grow, which is why the network is just
humongous right now, and that's why it's probably not gonna go away any time soon.
>> Yeah. >> So, here we're going look
at over some things about the original phone where it just has the microphone,
has the ear piece, or the speaker which is the receiver.
You have a ringer so you know when someone's calling you.
And you have some contacts or addresses so you know who to call.
And all of these are also encapsulated in VoIP.
Right?
But, it tends to be less efficient,
because it doesn't really use the bandwidth that well.
Because everything's just on analog.
>> Yeah, so when it comes to the old school telephones.
I don't know, maybe some of you remember because you still use the old school
telephones, the analog phones.
But you have to have all these other devices, you have your phone but
if you want a Caller ID, you have to hook up a Caller ID.
If you want a message machine, you have to hook up a message machine.
All of these things just come integrated- >> That adds up to have a overhead cost.
So, the old telephones didn't have more, but
often times with VoIP phones everything's already integrated, like software, or
just simply all in one package.
So, with that begs us to ask the question,
if VoIP is better then why is the PSTN still around?
And we just answered that earlier where it's humongous because there's been so
much time for the network to grow.
Because the analog phones came first,
Internet was not around until say two decades ago, right?
>> Yeah, so you have a huge network which means we still have to cater to that.
>> Right, so we have to find a way, if we're gonna slowly transition into VoIP,
we have to find a way to still be able to talk
to the old analog phones that are still on the PSTN network.
>> Mm-hm. >> Or PSTN.
And the way they do that, is, we would introduce a device that will just