WAN Communications

00:00

Our last section here is W. A N Technologies.

00:03

The vast majority of this course focuses on the Elian because we as network technicians, spend most of our time on the land.

00:10

We want a basic understanding of what happens when traffic leaves our network. If we're connecting to a branch office or if we're connecting out to the Internet or some other environment, we have to have an upper level understanding.

00:22

Yeah,

00:24

if we talk about when and communication, we generally have two options circuit switching networks or packet switching networks

00:32

and a circuit switching network. Anything that uses the telephone companies links will be a circuit switch network.

00:38

If you think about it. If I call my friend in Seattle, the entire voice calls through a series of switches. But the entire amount of voice data travels through the same set of switches types of networks that use this or dial up. But also I S D N networks are circuit switched the T carriers, which are T one and T three, and we have e carriers in Europe.

01:00

Anything that uses the Pots Network, which, if you're not familiar with that acronym, it's probably the most ridiculous acronym of all time.

01:07

The Pots Network is simply the plain old telephone system it's going to be circuit switched.

01:12

Mhm.

01:14

The alternative to circuit switch is packet switch with packet switching. Your data is chunked into packets, and each packet finds its best way to the destination.

01:23

The benefit is you get a decent speed improvement because the pathway that's best at the very beginning may not be the pathway that's best at the end. So every packet finds its best destination

01:33

frame relay and E. T. M. We're too early technologies that use packet switching.

01:38

More importantly, anything that's based on I p So all your I P networks are going to use packet switching.

01:44

Just about everything that we use today is going to be a packet switched network.

01:49

Mhm.

01:49

One of these is a VoIP network voice over I. P. We, at one point in time wanted to take a digital data and send it across analog phone lines, and then everything turns digital. So now we want to take that analog voice and put it on digital lines.

02:05

We've really always tried to run these two different signaling types across the same line, but they're not compatible, so we have to have some sort of conversion with VoIP. We call that telephone E

02:15

our smartphones of the devices that really do that conversion for us back when we're connecting across analog lines were using Bonhams. VoIP used RTP, which stands for real time transfer protocol. And that's the protocol, which exchanges data and it does not secure by default.

02:32

We need to add security to devices that were developed in an unsecure manner,

02:37

the same idea that's been coming up.

02:40

We move on to multi protocol label switching, and this is a technology that's replacing a lot of the branch to Branch VPNs. So instead leasing a provider network.

02:52

The benefit of these labels is once again quality of service, being able to prioritize certain types of traffic over others. So that way we can get most of our bandwidth, and we have the most efficient communication.

03:02

What we see here is we have to networks and then in the middle. That's the providers, Mpls Domain or network, and ultimately, on the border of our network, we have something called a label edge router.

03:15

That little edge router is going to be what assigns the label to the traffic again based on prioritization needs.

03:23

It then goes through a pathway of various routers, and we call that pathway a label switching path

03:29

on the other end. It comes out through a label edge router that strips away the label and passes the data along to the IP network.

03:36

This is just a provider network that we use to connect office to office because we're not transmitting across public Internet like we would with a VPN. We have some additional security as well.

03:50

When we're talking about W. A N and Elian traffic, there is a point called the Demarcation Point or the D Mark and that mark. It's the point where the Elian ends and the W A N begins.

04:01

We need a device that takes this land traffic and connects us out to our service providers networks that we can participate or send traffic across the land.

04:11

We use T carriers like T one or T three lines use something called a channel service unit data service unit, and that would connect us specifically to the data terminal equipment that really was our router. In most instances,

04:25

there's also a tool called Smart Jack that allows the W A N provider to diagnose, possibly even reconfigure elements of our land connection.

04:35

Mhm.

04:36

The last topic we look at is software defined networking software. Defined networking is an arena that is just becoming more and more popular today because what we're looking at is moving towards a virtualized environment where everything that we do is essentially virtual with software defined network being able to control our network configuration through the use of software tools

04:57

as opposed to cabling and re cabling,

04:59

and going to specific routers and logging onto those routers with credentials. And using the command language native to that router switch is now going to be a matter of clicking drug interfaces and reconfiguring our network with a mouse. That's the direction that we're headed, and it's already there were certainly beginning to see that utilize more and more with cloud computing.

05:19

This was a massive module. Massive, massive, massive module are key takeaways. We looked at static routing, which requires we create a manual route throughout the route. Add command to specify were routers send their traffic. We can also enable dynamic routing protocols like R I P O S P F or B G P, that allows the routers to learn the network environment in the best path for themselves.

05:44

Many routers, but also firewalls and proxy servers, offer a service called N a T Network address Translation, which works with port address translation.

05:54

Ultimately, that allows hosts to hide behind a NAT device. All traffic presents itself with the source address of the NATS Devices external interface. So it kind of keeps us safe behind that.

06:05

We also looked at lan connectivity and talked about circuit switch versus packet switch networks and then discuss software defining networking and that being the way of the future with virtualization