so, Hobbs, you don't see helps around much anymore. They were the predecessor
They operate on the second layer
the same device. If using a start apology, it basically functions. Repeater switches You have dedicated band with each port, but Hub one, bam one Bandwidth was shared between all the ports, so foreign port was using more bandwidth in the other.
Too bad it, you'd see decreased performance. You could also see everyone else's traffic. There's no segregation of the traffic at all, so it was easy to pack it. Smith Packet sniff All traffic going across Hub
It's the weakest of all. The securities
Bridges are like dumb routers. They could be used to connect networks together. Two different networks.
You can do bridges and a good example of a bridge. You can do a bridge on say you into a software based bridge on your Windows machine. So if you have a
you have a wireless nick or you have a
you have a VPN connection or wire. You have wireless Nick that's talking out to the hotel Internet, and then you have your internal,
uh, wire Nick talking to a different network
plug into a switch, say to a different network. You could bridge those two connections
through the software and window. So then everyone on your
on your little subject you've just created can go bridge through your laptop to get out to the WiFi network. And they could be in there two different networks with two different I p schemes. And it's creating a bridge between the two.
So there's hardware device that do that, too, but they don't do any of the other stuff like a router does, like
or static routes or dynamic routes.
Modems they operate where one,
ah, the physical layer. Because modems they're like next. So their way of getting data
transporting data. So modem very popular. Before, we had
fast Internet and our homes,
usually a dial up over a telephone line,
basically converts digital analog and then back again.
We used access network remotely.
They have very little security to him. They don't do compression.
I mean, they don't do encryption
most of time. The best you'll see is the user password check, username, password.
You could also check the caller I d to make sure it's coming from an I P. It's coming from telephone number that is allowed to call in
Or you could use a call back where the moon will call a predetermined number. After Jozic successfully authenticates
Switch was mentioned switches quite a bit. Here they operate layer to or layer three. If they're smart, switch.
What kind of a hobby combination of ah ha been a bridge?
A lot smarter than a hub,
and they have higher performance in a bridge. They can use what's called V lands or virtual local area Networks will talk about that in a second,
where we can segregated network logically
on one switch as opposed to multiple switches.
The support port security. So we could say only a PC or a nick with this Mac address can operate on this poor
so people can't just go plug in any PC into your switch and get access. The network. We can check with the Mac addresses, and if it's not in authorized Mac address,
it will not be allowed to
A Layer three switches or a smart switch also is allowed to make wrong decisions,
so you could say traffic and go to
one network has post the other
your basic switch wouldn't do. That
switches into traffic management where they learned where hosts around them by maintaining a Mac address to physical port pairing.
This is called art or dress resolution protocol.
So it takes the grabs, the Mac address off the front of the header off the packet when I first tried to communicate on the network and use that to map it to which port it's coming from.
And that's how it knows where to send traffic.
All these all these translations
are kept on what's called the content addressable memory table.
This contains the art data,
but inherently they're not security devices
So we have physical switches that we can use to separate combined computers together. And these switches would usually talk to a router, and they would all be on the same network.
Now, if you want to be all run multiple networks on the same switch we can use was called Villains and weaken segregate certain ports off into separate networks.
So even though we have eight p sees on the same switch,
we can make it so that
those eight PCs can't see each other because they're on separate networks logically,
you know, they're plugged into the same physical switch
switches Port port. Marrying this is goes back to like. So with the hub,
all traffic is broadcasted. All ports were not using heart. We're not using our We're not doing that translation of which Mac address comes from which port, So we don't know where it's in data to. So that made it really easy to watch all traffic going across that hub.
And that's very bad from less user. But if you're doing it as a system administrator, where you want to be able to do security filtering our analysis on all the traffic going across the switch, you can set up what's called port marrying,
where it will watch all the data going across any switches you put in that port marrying group and you can watch you can do analysis on it.
So it makes a mirror of all the traffic going through
very similar dial hub usedto work. I mean, it's not something you want to leave on all the time. There's a performance hit, but
power Efren Ethernet a lot the higher and switches that you'd see in a corporate environment a lot of them support. It's called Party Over Ethernet,
which allows you to power devices through these in that cable.
you start seeing that with stuff like voice right P phones. So instead of having a separate plug,
you can just plug it into
a Cat five or standard network cable and now provide power.
Also, uh, another common uses I p surveillance equipment.
Sarah, you don't have to worry about running electricity to the side of the house
where you wanna plug in your camera because it can receive its power over the Ethernet cable very similar to how phones
worked. You never had to plug in your phone unless you had a lot of extra features on it. And a lot of us don't have landlines anymore, but it's a small amount of voltage enough to power the phone.
It's the same concept with par or Ethernet.
The standards at the fine. How power either networks.
You need to have at least Category five cable for
for most devices like voice right P phone
but can function over Category three and a lot lower rate.
Category three Cable is the same kind of cable that you use for your telephone
that a network cable
firewalls are secure device that control traffic entering or leaving a network. So we have all our traffic. Finally, goto one point to get out the Internet
so we could put a firewall there, which could monitor for malicious activity,
filter out most activity or control. What kind of activity won't allow in and out of the network?
This is the more commonplace that you'd see
your port filtering in your access control less the block traffic
blocking on where it's coming from, where it's going from. What kind of application
is trying to go through your network? What service if its web of his D. N s,
another network components network storage is. We have two kinds that we're gonna talk about. A NASA, which the network attached storage.
Basically a hard drive plugged into a network that you can use to save files, too,
that need to be plugged into a server or anything. It's usually a standalone device with just a network card attached to it that has three or four hard drives in it,
and then other machines on your network and use it like a window share
You want to set up an entire server to share files over the network. You can use a network area a network attached storage
to as opposed to a sand, which is basically a huge,
facility, has a lot of hard drives in it, But
it's all story one place, but you're it's accessible over the network, just like nasty as opposed to it being the entire store space being shared. Your mapping that to an individual user machine.
So the host thinks he's has his own hard drive when it's really stored in a storage area network that also contains other people's hard drives. It's one big pool of storage that is segmented out
for specific purposes,
so a sand will be larger than a nasty
her network attached storage.
Now we mentioned voiceover. I appeal of it before,
with less and less use of regular landlines,
people are using voice over I P, which allows you to make telephone calls
There's two kinds of voices right piece to consider. There's voice right P where it's only gonna talk to other phones
that are on voice of right P within your network.
If you want to talk to regular telephones at some point, needs to talk to a server that's gonna convert that into a standard telephone line and make a call out to a regular phone number so you can have it be an internal only solution where you come in with your own dialing scheme. It doesn't
days like a huge internal intercom system
where you can have it interface with what's called pots playing a telephone system where then you can use it as a regular telephone to call out
runs over a stair network cable sometimes have passed through where you know, instead of having to networking was coming off the wall, you can have the network cable come out of the wall, go into the phone and then from the phone house, another Jack that you can plug into your computer So you kind of daisy chain.
You don't have to, Jax
Voice over i p. You can. Still, it provides a live additional functionality that would be hard to implement on your own. In a traditional phone system where you can set your own voice mail, you can have it tied into
maybe your your enterprise identity solution that would have
email addresses and other contact information.
A lot of other niceties. You gonna sign?
Picture to your identity. So when you call, everyone can see what your picture looks like. Ah, lot more of those. Nice to have that you'd see using a computer.