IP discipline, networking.
Hello, everyone, and welcome back to the course, as this is the first section of that course here,
we're going to actually offer some videos and lectures that are talking about the essentials, about
the networking concepts.
And we're going to focus strongly on the discipline diaper stack.
It is very important for us to mention that this section and all the sections of the above are based
on the Internet protocol, version four and version six.
So if you don't know what this is, basically Internet protocol version four is the database of all
IP addresses that are possible to be taken in Internet and IP version six is created due to the fact
that IP Version four already is started running out of IP addresses, even though there were billions
possible other races with the IP version four.
But now, since they are taken to the export of Internet, now, we're also using the IP version six
IP address type.
So the IP in the IP set of protocols are designed to work together to provide an end to end transmission
of messages across different interconnected networks.
So usually we say that the protocol works in the transport layer while the IP protocol works on the
network layer.
So the DP is responsible for creating connections through a data flow.
And this is because this process guarantees that the data delivered to the destination is without any
errors and it is delivered basically in the same order in which we send it out.
On the other side, IP is responsible for sending and receiving data blocks, so they move the IP users
to find the right IP address or the right roll to a system.
But it pretty much doesn't guarantee that the that the data actually is reaching the right destination.
And for that reason, we're usually using the TCAP and IP at the same time.
So actually, let's talk about the similarities about that.
Espin they basically both of the protocols are used to solve the transmission over data generated in
the network and aim to be transmitted internally or externally.
The union basically of those protocols is then to ensure that information always arrives on the best
road and on the correct destination.
So let's talk now about the protocol stack and the different layers incorporated within this protocol
stack.
So basically the protocol stack his exactly four layers.
The first one is called the application layer.
And this layer pretty much manages the high level protocols, including representation, coding and
some that will control issues.
It handles everything that is related to applications.
So an example for application, there would be telnet, which we always use, for example, to connect
to certain devices that are, for example, connected to a router which actually has an IP address.
And let's say to that router, you can connect more than one device.
Right.
So these devices are going to be at the application layer.
Then you have the transport layer.
And this layer basically handles the quality of the service, the reliability, the control or the flow
and the errors as well.
So one of those protocols is exactly that GCP protocol, which aims to provide a reliable network communication
and some order of the connections.
So the transport there could be either with Tsipi protocol, which gives unordered connection to a device
on or UDP where there is no order connection, which means that when we send messages, there is no
guarantee that they are going to be received in the same order that the data they've been sent.
Next one is the network layer.
And basically the purpose of the network layer is to send packets from the source to any network and
make this packet to reach a destination regardless of the route that they actually use in order to get
there.
And the final layer is called the network access there.
And this is also called the host to host the network layer.
It includes the one and the W8 and protocols.
They are also known as link layer or data link layers.
So we can say that the network assessment is basically the interface layer to the current.
Network hardware.
So if we check the next diagram, we can actually see the different layers and what they basically control.
So on the top level, as you can see, we have the application layer with the SMTP or the Telnet commands
in order to assess devices.
Then we have the transport layer, then the network layer, which is the IP address basically.
And finally we have the network layer, which is, for example, the wireless or the one that's C.
So the network layer is basically when you connect to the Internet, then we get a network, which is
the IP addresses, then we get the transport of that IP address and finally we reach our application.
This is basically how it works.
Everything that is related to connecting to some service on the web or locally.
And usually the IP address is the most important protocol in the network.
And even though is the most important, as we already said, the IP address does not provide any reliability,
flow, control or error recovery.
And is it because IP is simply a way in order to name a device or service on the Web or locally?
So the protocol that is basically responsible for the reliability and the recovery is the Tsipi protocol
or the UDP protocol, both of them, they're used in the transport layer.
So when you want to send some data over a network, this is called sending an IP diagram.
So this basic unit or this diagram is transmitted from one site through the pipe network to another
site.
Also, the application layer is basically the layer where the user interacts with the computer, where
actually the services or the action occurs with the actual system that we use.
And even though it forces some browsers over Internet, we actually do use them in order to connect
to the application layer or to communicate with the application layer.
So we log into the browser and then we communicate with the actual through service that is somewhere
around the world on their site.
If we want to access a remote document, we can use the HTP protocol, which is basically everything
that we've seen the beginning of the name of each website.
Each time we request a communication of this type, the browser actually interacts with the application
layer.
So it actually serves as an interface between the user application and the protocol stack and finally
provides a communication with the lower layers.