Ethernet
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00:00
Wyatt Networks these days are built around something called Internet
00:05
Now. Ethan. It was not always the only standard that was used in the early days of networking, and I'm talking about. Back in the 19 nineties, there were actually two competing technologies.
00:17
One was Ethernet and the other was token. Ring
00:20
Internet was pretty much an open standard, and therefore many different vendors produced Ethan at hardware,
00:27
and that tended to drive the prices down.
00:30
Token. Ring, on the other hand, was a proprietary IBM technology, and since IBM kept the price is high because they could,
00:38
they eventually actually shot themselves in the foot. Because what happened over time is the cheaper Internet technology took over and token ring pretty much vanished. So you're not likely to find token ring technology around these days. So all current local area networks are built around Ethernet.
00:59
Wired networks obviously require wires to connect devices together,
01:03
and what happens in a wired network is your data is converted into a series of electrical signals that is high and low voltages, and they're sent down the wires between devices,
01:18
the cables that we will use our sometimes just called patch cables. But Technically, they are Internet cables.
01:26
The maximum recommended length is 100 meters, and the cable is terminated at each end with R J 45 plunks that look like this.
01:38
Not all Ethernet cables, though, are equal.
01:42
Internet has evolved through a variety of different standards. The earliest Ethernet networks were
01:48
operating a 10 megabits per second.
01:51
Then there was what they called fast Ethernet that operated at 100 megabits per second. But these days, what is commonplace is
02:00
Ethernet that operates at one gigabit per second
02:04
doubt.
02:05
These days you may find that there are
02:07
let cables that are labeled as Cat five
02:10
and other cables that are labeled either as cat five E or Catch six.
02:15
Now, depending on the speed supported by your home writer,
02:19
you need to use one of the other cables so
02:23
you might find if you have a modern home router
02:25
that it operated one gigabit per second.
02:29
So in that case, you need cat five e or CAT six cabling to support that speed
02:34
older home raptor, which may be only support 100 megabits per second. You can use any of these cables with those
02:44
when laying the cable's out you should take care to keep them away from sources of electromagnetic interference.
02:51
Now am I is generated by anything with an electric motor in it.
02:55
For example, vacuum cleaners and refrigerators were generating electromagnetic fields, but also so does fluorescent lighting. The older see Artie displays and mains electric cables.
03:08
So be careful that you don't lay your Ethernet cable right next to a mains cable.
03:14
The Mains caper will generate strong electromagnetic interference,
03:17
and the way electromagnetic interference made manifest itself is that you find that the speed of the network it's slower than expected.
03:28
In other words, it lowers the effective bandwidth off the connection.
03:36
So typically, you're gonna need atleast two Ethernet cables to start setting up your network. One of those cables will connect to the cable modem,
03:45
and from there it will connect to the home router.
03:49
If you look at the back of the home router, you might see that there are several R J 45 sockets. So here, for example, the one labeled number four is also labeled his landline.
04:01
So if I was running the cable from the cable modem to the router, I will plug it into that port the one that's marked either's line wine, where it may just be marked as one.
04:12
The rest of these. So, for example,
04:15
these ports 32 and one
04:18
those could be used to plugging laptops and desktops and so on.
04:23
If you look carefully at these ports,
04:26
you will see the following
04:29
that there are two lights on the sockets,
04:31
and this is true off the socket at the home writer, And it's also will be true of the socket you plug into in your computer.
04:41
And these two lights indicate the following. There will be one light that is steady, and that indicates that you have a connection between the two devices
04:49
and a second light that you'll see flickering and flashing, but only when data's being transmitted or received through the cable.
04:58
So that verifies that you have, ah, working connection and data is actually getting transferred from the computer to your home wrapped up.
05:08
You may find on the home writer that the lights are in the back as they are in this picture,
05:14
or you might find that the lights actually at the front of the device you need to look around.
05:20
What about wireless connectivity
05:24
well, most of us think of wireless as WiFi, and we will talk about that. But first we're gonna have a look at something called Bluetooth, which also represents violence connections.
05:39
So blue tooth is wireless connectivity using radio waves.
05:43
It's designed to operate only of a very short distances up to 10 meters or less,
05:48
and it provides a point to point connection. So, in other words, in directly links to devices to each other,
05:56
this is un contrast to WiFi.
05:58
Um,
05:59
in WiFi, you can have one device connecting to many other wireless devices through the WiFi network,
06:06
but Bluetooth is not designed in that way. It's designed to provide a direct connection just between two devices.
06:13
So typically, those two devices would be things like the keyboard or violence keyboard that connects to your PC or a violence mouse that connects to your PC.
06:23
Bluetooth is often also used for connecting speakers or headphones to your device
06:30
on DDE.
06:31
Sometimes Bluetooth is used to allow you to connect your smartphone to your desktop computer, and then you could transfer files back and forth between the phone and the computer.
06:44
Another way of connecting violas Lee to the Internet is through cellular connections,
06:49
so this is basically yourself found being used to connect to the Internet.
06:55
Now the most basic types of cell phones may only provide a phone connection,
07:00
but most people also want Internet access on their smartphone. So first you need to sign up with the cellular network provider such as Verizon, T Mobile 80 and Teen Someone.
07:11
And then you need to sign the contract for the amount of bandwidth you're going to use. So some plans will offer you two gigabytes, or four gigabytes or even unlimited access.
07:23
Usually, the unlimited is not exactly what it says.
07:27
When you sign up for an unlimited plan, they still often have some kind of threshold, such as four gigabytes.
07:32
And then what they do is you exceed the four gigabyte limit.
07:36
They don't disconnect you, but they just throttle the speed down and slow you down.
07:42
So you've I want to check when you sign up with a plan, whether unlimited actually means unlimited.
07:51
What about connecting devices to the cellular networks? But these devices are not
08:00
smartphones.
08:01
Well, in that case, you can do this.
08:05
You can purchase from your self cellphone provider. Some little device like you see in this picture
08:11
Now what that does is it connects to the cellular network just like your phone would,
08:18
and then it creates a little WiFi network. So, for example, your laptops or desktop computers, if they have WiFi adapters,
08:26
they can connect to the little device and that device that connects them through to the Internet using your cell phone data line. So now let's look at WiFi.
08:39
So what is WiFi?
08:41
WiFi refers to generalize networking that is wireless.
08:46
So no, why, as required to connect devices together.
08:50
Instead,
08:52
your data packets are converted into radio waves and then broadcast into the air.
08:58
Typically, smartphones, tablets, laptop and desktop computers can connect using WiFi.
09:05
If Wife I support is not built into your desktop computer,
09:09
you can always get a WiFi network expansion card. Install that and then give it WiFi capabilities.
09:18
WiFi is controlled through a set of standards that are defined by IEEE.
09:24
IEEE is the Institute of Electrical and Electronics Engineers.
09:28
Over the years, there have been many different WiFi standards, so it began with a door to door 11 a.
09:35
And then we had 11 be livin G. Levon n and the later standard. It's a door to door 11 a seat.
09:41
These days, when you purchase, for example, a home router, it is likely that it is either an 11 N or an 11 a c Home writer.
09:50
As
09:52
you might expect, one of the differences between these standards is the speed at which they connect.
09:58
So, for example, 11 a networks could connect it up to 54 megabits per second.
10:05
But the latest 11 a seat standard,
10:07
can connect at up to a gigabit per second and in some cases, under certain conditions, it may even be able to extend up to seven gigabits. But second now there's no actual devices around that I know of at this point that well connected that kind of speed.
10:24
But there are devices that will connect it up to a gigabit per second.
10:31
If you are connecting together the home router and various wireless devices, they all have to support a common standard.
10:39
For example, if you're home rather support 11 n,
10:43
then your wireless devices should also support 11 n,
10:48
and so must your operating system.
10:50
So you have to make sure that there is compatibility now, some of these standards are backward. Lee compatible, for example, and 11 n router
11:00
should be able to accept connections from devices that are 11 B or 11 g.
11:07
But other standards are not compatible.
11:09
For example, 11 a C.
11:11
Home writers may not allow 11 B or 11 G devices to connect to them. You really need to check with the specifications that come with the home router to see what standards and earlier standard that supports.
11:26
And it's often the case that what happens is your home drafter gets upgraded to the latest standard because you go out and buy the latest home router.
11:33
But many of your devices are older and may not support the later standard. So it is important to make sure
11:39
that the home rocker you're purchasing will provide backward compatibility for any devices that operate over these earlier standards.
11:50
Now, in order to set up a WiFi network, you typically have to configure your home router,
11:56
and it used to be the case that you would usually do that by plugging in a wired computer into the device.
12:03
But we're increasingly starting to see home routers, which could be set up wirelessly, often by using an app installed on your smartphone or tablet
12:16
and usually the management interface that is used to set up and manage. The writer is configured as a Web page,
12:24
and so the way you connect to it
12:26
is you open a Web browser and then you type in the I P address off the home router.
12:31
If you're not sure what the I. P address of the home Ratter is, read the documentation,
12:37
but very commonly it is either 192.168 dot 1.1 or one night 2168.0 dot one.
12:46
So in your browser, in the address bar you were type in http colon slash slash 192.168 dot 1.1
13:01
In terms of making sure your home router is secure,
13:03
probably the single most important thing to do is to change the administrator password.
13:09
These devices come with a default admin password,
13:13
and that is a problem because if a hacker can figure out the make and model off your home writer,
13:20
the first thing they're going to try when they taught a hack into your home router is that default admin password, and we talked about this earlier in the course,
13:28
so you might want to do that. But the other thing that you will want to do is this
13:35
many hell. Proctor's allow management through the WiFi
13:39
and allow a remote management
13:41
well.
13:43
Allowing management through the WiFi is also potentially dangerous because this means somebody who's outside of your building could try to tap into the WiFi network and to log on as an administrator.
13:54
Similarly, remote management. It's a bit of a problem because well, that is saying is somebody on the Internet is allowed to come in,
14:03
log on to the home router with the admin account and manage it
14:07
in both those cases. You are
14:09
trading convenience for security.
14:13
It is convenient to be able to manage your home router through WiFi or remotely from another location.
14:20
On the other hand, that also provides an avenue that hackers could use to try and get into your home wrecker.
14:26
So probably it's a good idea to simply disable
14:28
wireless management and remote management off the home router. That way, the only way to manage your home router is through a wired connection.
14:37
So if somebody wants to hack into your home writer there would have to gain physical access to your home or your office, plugged themselves into the writer, like with a laptop, and then they'd be able to try and manage it.
14:54
So herewith seeing how
14:56
to change the administrator password
14:58
In this case, the home router is a lynx is e a 35 100.
15:05
And
15:07
we're also seeing how we can disable WiFi connectivity and disable remote management.
15:13
Now, just be aware of this that
15:16
here we're showing you the interface off a specific make and model.
15:20
And what you will find, of course, is with your particular home router. It may look different. The administration page, however, they typically will have all of these settings available. So it may be a matter off clicking around to find these settings.
15:39
The other major setting you might want to change Is this
15:43
the s s I d.
15:45
Now the s s I D. Which stands for service set. Identify is really just the name off the WiFi network.
15:50
Unfortunately, again, what happens is home raptors come with a default WiFi name.
15:56
And that was a problem, because
16:00
if somebody is trying to get into your WiFi.
16:03
And they see that, for example, the WiFi is called link sis.
16:07
That gets him a clue.
16:08
It tells them that the make off your home router is Lexus.
16:15
So then what they do is go on the Internet and the search for vulnerabilities.
16:18
And you can see I did a little search here and found a couple of vulnerabilities that exist in Lexus routers. Specifically the model that I have,
16:27
which is the e A 35 100.
16:32
So any hacker will also try that as well, once they figure out what make your home rotaries.
16:40
So let's have a look at changing the S s I d.
16:45
So here we're changing it from the default
16:47
between sequence iwas Cisco, which gave things away a little bit
16:51
to something obscure.
16:53
Ah,
16:53
what we say something obscure. We've bean this,
16:56
that
16:57
the s s I d should also not only not give away what make and model your home router is.
17:04
But also it shouldn't give away anything else about the WiFi network. For example, it's not a good idea to give it a nets aside the
17:12
based around your name or your company's name,
17:15
because remember
17:17
people with a device like a smartphone just walking by the building will see that WiFi network.
17:23
And if they can see a name and the name is obvious than they know, you know which network it is that they're actually seeing.
17:30
So probably not a good idea to use your name, for example, for as the name of the WiFi network or the name of the company as the name off the WiFi network.
17:41
So truly choose something obscure
17:48
and then you have to choose a security mechanism.
17:52
Now, WiFi, when it was first released, came with something called weap Webb stands for Wired equivalent privacy
17:59
and what they were implying, of course, with that name is your WiFi network was as secure as you're wired network.
18:06
This was kind of ironic because pretty soon after, weapons released, many vulnerabilities were discovered within it.
18:12
So you should never today set up WiFi with Web security
18:18
unless we really don't care about the security. For example, if you were setting up a public WiFi
18:22
and the only thing it connected to was the Internet,
18:26
then you maybe not that concerned about security.
18:30
But if you are, you should not be using weapons.
18:33
Now there was an interim standard that was released. What's all the vulnerabilities in weapon being exposed? And that was called W P. A.
18:41
This was never really standard in other words, what we call a de jour standard
18:47
in the sense that he was never ratified by anybody like IEEE. Instead, W. P. A. Was a de facto standard that arose out of this.
18:56
WiFi vendors started to panic a little bit, once through the vulnerabilities in wet war publicized
19:03
what they were worried about. What people are going to stop buying WiFi products.
19:07
So they got together in something called the WiFi Alliance, and they came up with an interim standard that made things a lot more secure.
19:17
But eventually IEEE released an updated standard, and that was called W P. A. To
19:22
so that is the current standard. Any WiFi device that you buy these days would most likely support W p. A. To, and that is the standard you should use.
19:36
So what does w. P. A. To do for you?
19:38
It creates an encrypted connection between the wireless device and the home router.
19:45
It also provides for authentication of the device.
19:48
Now this gonna be done in two different ways. There is a personal mode and an enterprise mode.
19:52
If you choose the personal mode, you have to choose a pass phrase.
19:57
And whenever someone tries to connected the WiFi, they have to know what the past phrases and they have to type that in.
20:03
Our most secure way of doing authentication is an enterprise mode, but enterprise mode requires some infrastructure to be in place on your network.
20:14
So typically you need to deploy a radio server
20:17
and a certificate authority server on the network. First,
20:21
the certificate authority than issues certificates that I installed on your wireless devices
20:26
and those devices then use that certificate to authenticate themselves to the radio server.
20:32
Since most small networks and certainly your home network
20:36
doesn't have a radio server or a certificate authority,
20:40
that option is not really available in most cases for small networks. So in that case, small networks would use the personal mode where ah pass phrase is used for authentication.
20:55
So here, let's have a look at setting that up,
20:59
which using W P a too personal
21:02
and we're being prompted to choose a past phrase. Now, just as we discussed earlier about choosing a long and complex passwords that applies here as well.
21:11
So now let's have a look at how to connect a smartphone to a WiFi network.
21:18
Firstly, you might need to go into the network settings and turn on WiFi. If it's not already turned on,
21:23
then you'll see a list off available WiFi networks. So you're seeing the S s I. D or the names of those networks. You choose one and into the past phrase
21:33
and then wait to see
21:34
that it connects
21:36
and gives you Internet access.
21:42
Once you have connected to the WiFi, you need to verify that everything is working on. The simplest thing to do is on your device, smartphone or tablet or a laptop or whatever.
21:52
Open up a Web browser and try connecting to a website.
21:56
If that works, you have successfully connected to the WiFi, and the WiFi is connected through the home router and the cable modem toothy Internet.
22:11
One other security should be aware of is this.
22:15
Devices like home writers come with a built in operating system and that sometimes referred to as the firmware off the device.
22:22
Just as with normal operating systems from time to time, vendors release updates which fixed bugs or problems within that
22:32
firmware or
22:33
they're dealing with security issues,
22:36
so you should regularly check to see if there are firmware updates available, and if so, you should apply them.
22:45
So here we're going to the page
22:48
where we can check for updates,
22:52
and as long as you're connected to the Internet, your home router then checks to see new firmware
22:56
versions are available and you need to upgrade.
23:03
So in this module we have looked at
23:07
how to set up a wired connection to the Internet and how to verify that it's working.
23:14
We've looked at WiFi and the security mechanisms available within WiFi, including weapon W P A and W p A. To.
23:22
And just to remind you, we cautioned against the use of weapons
23:26
on dhe W p A. To is the standard that you should be using these days.
23:32
And we also looked at this that there are some basic security measures you need to take when setting up your home writer.
23:37
Change the default administrator password
23:41
change. The
23:42
S s I. D. Or the name of the wife. Five from whatever the default is to something more obscure
23:49
on DDE
23:51
that you should make sure your sign a long and complex past phrase to connect to the white fight.
23:57
Also periodically check for firmware updates and apply those as they are released by the vendors.
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