WAN Technology: Part 1

Video Activity
Join over 3 million cybersecurity professionals advancing their career
Sign up with
Required fields are marked with an *
or

Already have an account? Sign In »

Time
15 hours 43 minutes
Difficulty
Advanced
CEU/CPE
16
Video Transcription
00:00
>> Now in our next section,
00:00
we're going to talk about WAN technology,
00:00
Wide Area Network technology.
00:00
I want to let you know,
00:00
>> this isn't a huge topic on the exam.
00:00
>> It used to be more significant,
00:00
you'd see more questions
00:00
>> on the exam about WAN technology.
00:00
>> In a lot of ways I'm glad they've backed off on that
00:00
>> because most of us are going to be focused on
00:00
>> inside the network,
00:00
>> on the LAN communications
00:00
>> and the LAN security.
00:00
>> Usually we outsource
00:00
>> or we hire a service provider
00:00
>> to get us out to the Internet,
00:00
>> connect our networks together.
00:00
Most of our knowledge needs to be internal.
00:00
We still need to have
00:00
some higher-level understanding of
00:00
what goes on across the WAN.
00:00
We'll first off talk
00:00
about the two main technologies for WAN,
00:00
which are circuit switching and
00:00
now packet switching being more popular,
00:00
and then we'll talk about
00:00
the technologies that use each of these.
00:00
We know LAN versus WAN.
00:00
Our LAN is our local network.
00:00
It's usually confined
00:00
>> to the same building or perhaps campus,
00:00
>> but a fairly small physical area.
00:00
Now once we exceed that,
00:00
we move to a WAN.
00:00
Often we use WANs to connect LANs.
00:00
I've got my office in Washington DC connecting
00:00
>> to an office in New York.
00:00
>> We would be going across a wide area network.
00:00
WANs have slower communication.
00:00
It takes a lot more time to get traffic
00:00
>> from here to New York than it does
00:00
>> from my computer to the ones actually beside me,
00:00
>> and it takes different technologies.
00:00
Let's talk about circuit switching
00:00
versus packet switching.
00:00
Circuit switching, anything that uses
00:00
the public switch telephone network,
00:00
PSTN, or what we used to call the POTS network,
00:00
which is perhaps
00:00
the single dumbest IT acronym I've ever heard.
00:00
The POTS network is the plain old telephone system.
00:00
Don't we have enough acronyms to keep up
00:00
without making stuff up?
00:00
>> That's so ridiculous.
00:00
>> But anyway, anything that use
00:00
>> the phone network is circuit switching.
00:00
>> Let's say I make a call to my uncle in Seattle,
00:00
well, that call is connected
00:00
>> through a series of switches,
00:00
>> and for the entire duration of the phone call,
00:00
my voice data travels through
00:00
those switches in order, like a train.
00:00
The engine leads, everybody else follows.
00:00
We get there in order.
00:00
Some technologies that use circuit switching,
00:00
like we said, our modems using the phone network, ISDN,
00:00
Integrated Services Digital Network,
00:00
we don't look to ISDN as a big solution today,
00:00
but it was very popular at one point in time.
00:00
We still find a lot of people that are on DSL,
00:00
Digital Subscriber Links,
00:00
for their high-speed connection to the Internet.
00:00
We also have T-carriers,
00:00
>> if you remember, T1 and T3 lines,
00:00
>> and they're still around, absolutely.
00:00
But those are all taking advantage of the phone system.
00:00
Now, we also have packet-switched networks.
00:00
X.25 was the first to the packet-switched network,
00:00
and it's based on the idea that
00:00
the quickest path when a communication
00:00
starts is not necessarily
00:00
the quickest path in the middle
00:00
or at the end of the communication.
00:00
What packet switching networks do is they chunk data
00:00
>> into packets and each packet finds
00:00
>> its own best way to the destination.
00:00
Packet 1 may go from a, b, c to get to the destination,
00:00
and Packet 2 might go through d, f, g, or whatever.
00:00
But each packet finds its own best way
00:00
>> to the destination to get to the end
00:00
>> and then they have to be broken down
00:00
>> on the receiving end and they have to
00:00
>> be reassembled on the receiving end.
00:00
But ultimately, that provides
00:00
a much faster way of getting data
00:00
from point a to point b as a whole.
00:00
After X.25, we moved down,
00:00
we had Frame Relay Networks and ATM.
00:00
Those were very popular
00:00
>> for a while for packet switching networks.
00:00
>> Most everything today though,
00:00
goes across the Internet,
00:00
meaning that it's IP-based in nature,
00:00
and IP is packet switching
00:00
or is a packet switched environment.
00:00
VoIP, which is voice over IP,
00:00
the IP makes it packet switching.
00:00
MPLS, Multiprotocol Labeled Switching.
00:00
We're going across a provider's network,
00:00
going across their Layer 3 routers with IP traffic,
00:00
so it's still IP,
00:00
same thing with cable connections to the Internet.
00:00
Packet switching by far is the most popular today.
00:00
In this section,
00:00
we talked about circuit switching,
00:00
any technologies that use the phone system versus
00:00
the more current packet switching technology
00:00
>> that allows every packet
00:00
>> to find its own best way through the destination.
Up Next