Welcome to the third section off our course. It's about the computer network protocols and the meaning off the world protocol in the world. Off computer networks.
What is a protocol in the world of computer networks? It's a set of rules and agreements that governs the communication process. The process off sending and receiving it includes this rules and agreements. The addressing, the routing, the session management
and the editor recovery process is, if needed.
How to address the machines howto route messages between the machines, how to start and stop any session between any two machines. How to recover the loss or the application off any data between two machines.
The male Network The Post Network, The Courier Network, The traditional Merrin male network is an example of a network with a protocol. Imagine that you need to send and, ah,
a certain mail that is written on a paper and included inside an envelope.
You should write on the face off the employees that the address off the man you are going to send the mail, too,
and you will also have to write on the back of the envelope there. Address off yourself
this is a protocol protocol that dictates on you some rules and agreements on how to ride the address, where to ride the address and on which piece would you write the address, which, which is the envelope here? The envelope here includes the headers off the data
and the message itself, written
in a paper inside the envelope is that data itself that needs to be sent between the sender and the receiver.
The P S T M. The public switch telephone network is another network that is running through a protocol.
telephone has a unique number that is, ah, worldwide, not
repeated, and that is worldwide connected to the geographical location. Off this telephone, the mobile phone network is a network that has also a protocol. Each mobile phone number is unique. Each mobile phone number has a route toe, another mobile phone number in the world.
Each mobile phone number can
and the session stop and resume a session
with any mobile phone network over the world.
The layered model that appeared with the eyes OS I model has so many benefits in this
subject because this layered model allowed off separation off functions between the layers off the protocols
so a layer can be responsible off addressing another layer can be responsible off the recovery. Another layer can be responsible off the session management. This is the session layer. This is the transport layer. This is the network layer. Another layer is responsible for the network access, which is called the Datalink Lair.
Every layer in the several layers has its own responsibility and is served by the upper and the lower layers to it toe Act as a sender and receiver for data according to the process being done.
The most well known computer network protocols that appeared over history was the net very high. PX SPX, Apple Talk and the
well known and very famous. A standard protocol T c P i p
The TCP I P is the standard protocol over Internet D. C P I. P stands for transmission control protocol Internet protocol.
It's compatible with the eyes. Always I model. It provides interoperability between different hardware and software systems,
since it is standard. Since it is compatible with the eyes OS I model, it can be implemented by any off the hardware or software manufacturers over the world.
it's open for development. It is not owned by a certain vendor, so it is open for development by researchers over the world.
It provides reliability. It provides some sort off
connection orientation. It provides some sort of a recovery and reliability in data transfer as well as best ever delivery. If this is the future that is needed. And sometimes we need the best effort delivery feature when we are
caring about the speed more than the reliability off the communication. This is very obvious in the real time data in the audio and video data,
it is composed of a number of protocols. That's why we call it the TCP I people too cold suit. It is composed of a number of protocols in the application layer in the transport layer in the network clear that are built over each other to form the TCP I people to call suit.
It offers Web browsing, file transfer and email exchange. If this means that it offers the most famous and the most demanded and the most wanted
service is over the Internet,
D. C P I. P has produced version four
and has produced version six, and both are running version for is more common. Version six is the next version and it is the current version in some countries over the world for communication over the Internet. This is the TCP I P. Protocol suit. Let's have a look. Let's have a look at the upper layer that
that is composed off. Http ftp tell not SMTP
the N S t f T p R, p, C S and M P. These are all protocols in the application layer in layers. Seven off the eyes, OS I or let's say that it is in layer seven and six and five in the eyes. OS I model and it is in the upper layer in the D. C P i p the transport layer which is the layer four
in the eyes. Always I'm modern
includes here anticipating I p two protocols. One of them is reliable. That is, the TC people to call the other. The other is unreliable, which is the UDP Protocol
that will clear the third layer in the eyes. Always I model is translated here in tow one layer
that is called also the network clear, including the I P Protocol as the main protocol and other protocols such as the ICMP. The are there are India. The dynamic routing protocols here These this layer is responsible for addressing and routing the lower tour. There's the data link and the physical air includes some off the
protocols responsible for accessing the network for a data representation and the functionality off the physical. And they telling clear, such as the Internet, the token ring, the FBI, The A T M a. T M here means a synchronous transfer mood and eyes the end Other
protocols that are responsible off transferring data representing ones and zeros accessing the media, a violent collisions and such functionalities off the day telling and physical air off the eyes always I'm on it.
Let's here have a look
more in depth about the mapping between the TCP I p and the eyes os I model. That s e p I. P is seven layers. We all know this, but the recipe i p model is only four layers.
You can see that the upper failures has bean murdered together to form the application layer in the d. C p i p.
The transport is still the transport The network has been translated as it is with the name Internet and sometimes called the transport as well that lower two layers are they telling and physical and are called the network access layer in this D c P i p. So let's say this again. This
mapping between the eyes O S I and the TCP I p has done through merging off some layers Toby
four in the TCP I p model instead off seven in the eyes Os I modern. This has done through merging the physical and they telling keeping both the network and transport layer merging the upper three layers in tow. One layer called the application layer
the TCP I P is now that the fold protocol that is implemented inside any Microsoft Lennox
or any other operating system that needs to be standard that needs to connect machines over the Internet, DCP I. P. Is now Standard is now built in inside Microsoft operating systems. Lennox operating systems and other operating systems that are produced on machines needs to connect over Internet.
Let's now have a look at
the mapping between D c P I p. The eyes always I
three layers has become one Layer application presentation session has become the application and example protocols that are learning in the application layer off the TCP I p r The actually Tippi, tell that ftp SMTP Deanna's R I P, which means routing information protocol as an appeal, which is
simple Network Management Protocol D and as the domain names their system or server
SMTP Simple male transfer protocol, FTP file transfer protocol and tell that is used for remote administration.
The transport layer is mapped in the TCP I pee in tau host to host transport layer.
This is mapped in tow, either TCP in the reliable communications or UDP. In the unreliable communications, the network layer is mapped through the Internet layer. The I P layer is the main layer that is the main protocol, or the main layer working in the network layer
upper to it. We can find ICMP Internet Control Messaging Protocol or a GMP Internet Group Management Protocol and the AARP, which is the address resolution protocol which is responsible between the
resolution between the two types of addresses, the Mac address, the I P address, the physical address and a logical address. As we will see later, the datalink and physical layers are Matt here in tow, one layer that is called network interface layer and is implemented in several
protocols in the TCP I p, such as the Internet, which is the most commonly used over today's networks. The token ring, the frame relay networks and the A T M.
This is the core off the D c p i p.
mapping between the eyes OS I model and the TCP I P Protocol. Thank you.