In communications between computers, there is what is known as computer networks. These are the ones that allow each of the processes within a network to run in order, making it possible to exchange information between computer systems.
The world of network protocols is really interesting, since learning from it involves getting your hands dirty with the most essential concepts of digital communication at a clear technical level.
In this article we are going to teach you the most important thing about network protocols, so you can use it to study for your institute exam, or simply to expand your knowledge about it. So pay attention and save this entry among your favorites .
Index:
What is a network protocol and what is it for in a computer system?
A network protocol is a set of rules established in a computer system that dictates the guidelines that must be met, to achieve effective communication between the nodes that make up that system. It is in a way like the rules of transit of the information that flows in the form of bites from one team to another.
This is very important, since without them, the information that is transmitted would not be verified, which would make nothing guarantee that it arrives without errors. Then, this becomes something like a means of communication; full of speculative information and doubtful providence . But most importantly, the orders it contains would be poorly applied, causing the applications that execute them to collapse completely.
In a way, the protocols are like supervisors: a filter of quality control of the data transmitted in the network. Thanks to them, you can achieve perfect harmony in the entire computer system , in which everything works as it should be.
What are the main network protocols that exist in computing?
In the same network of computers there are a tremendous number of protocols, naming them all would take us here much more than an article. But the most important and well-known will be named below:
Internet Protocol
Possibly the best known. This is an unreliable data transport protocol. What it does is send data packets (datagrams) from one point of origin to another destination , limiting itself to this and not ensuring that the packages are delivered.
This very basic concept is the basis of Internet communications. Since it sets an address to your computer (IP address) and gives you the ability to send data (upload) and receive (download) . There are two known versions of this protocol, IPv4 and IPv6, and the main difference between them is the number of addresses that you can assign.
ARP
Less known but very important. It works together with the Internet protocol version 4, and is responsible for assigning IPv4 addresses to the corresponding equipment. It’s a simple task, but it makes things a lot easier. Its initials correspond to Address Resolution Protocol or address resolution protocol .
However, one of its weaknesses is that it does not verify that the addresses it assigns are correct, which allows for errors.
ND Protocol
This protocol has exactly the same function as the previous one, but in this case it is responsible for assigning IPv6 addresses. In this way it allows a device to integrate into the local network , being a link so that the datagrams reach this one.
ICMP
This is another protocol that works in conjunction with the Internet protocol. It is known as Internet Message Control Protocol or Internet Control Message Protocol, and this is responsible for sending notifications and error messages , informing scenarios such as that the host is impossible to locate or that a service is already not available at the time of your request.
TCP
This protocol is mounted on the IP, which often makes both known with the name TCP / IP. This has exactly the same function, since what is responsible is to transport data from one point to another, with the difference that in each data you add a checksum or checksum to ensure the reliability of the transmitted data.
Its initials correspond to Transmission Control Protocol or transmission control protocol.
UDP
This is a protocol very similar to the previous one, but it is responsible for the transmission of data in local networks of the same user, without depending on Internet connection. Like the IP, does not guarantee that the data will be received, but this in turn speeds up communications on the network.
What is the OSI classification? What are all the layers that make up this communications protocol?
In the world of network protocols, there is a reference model known as the OSI classification, which is a standard created by the World Organization for Standardization (ISO) in the 1980s, which determines a basic scheme on which they should Be governed by the different protocols that exist. This is not the only one that exists, IBM also created its own System Network Architectura (SNA), but the OSI is still the most popular .
This model consists of 7 layers with different functions that allow communication in a network to be 100% effective. The user only interacts with 2 of them: the first and the last respectively, since the others occur at the system level.
Here are each of them:
Layer 1 (Physical level)
The physical layer is the one that is worth the redundancy, is composed of all the physical elements of the network, from the machines or computers, to the cables and routers . This also encompasses the concept of network topology, which is nothing more than the way in which a network is structured to facilitate communications in it.
This is the layer with which the user has the most interaction , and it is even said that it is the only one since the seventh layer, the application layer, is not executed by this one but by softwares that this one uses in this first physical layer.
Layer 2 (Link level)
Known as the data link layer. It works between the physical components and the network (layer 3). It is responsible for processing, verifying and confirming the data issued at level 1 of the OSI model , and then sending it to level 3, which is where the process of sending and receiving information between computers really begins. p>
This layer is essential, since is a filter to ensure that the data entering the network is correct , as the protocols of the network layer, in most cases not They will be able to do it because it would reduce their transportation fluidity.
Layer 3 (Network level)
This layer is where most of the protocols mentioned above live together. It is responsible for sending the data from a source to its destination , regardless of whether both points where they are directly connected or if there is a “intermediary” device between them. p>
The most important element of this is the Internet Protocol (IP) that we already explained in the previous point, and works together with hundreds of other protocols.
Layer 4 (Transport level)
It is often confused with the previous one, since it has almost the same function when transporting data from one IP address to another within a network with or without connection to Internet . For this it uses the protocols TCP (with connection) and UDP (without connection), which work on the Internet or IP protocol. What this does is that it makes the data of the network layer independent, to make its transmission from source to destination much faster.
Layer 5 (Session level)
Each time an exchange of information between computers begins, what is known as a “session” opens. This level is responsible for keeping this session open while the data exchange takes place , otherwise it could not be completed and communication on the network would be completely impossible.
This is also able to resume a session in the event of an unexpected interruption, resuming it from the exact point it was interrupted.
Layer 6 (Presentation level)
This is one of the most important layers. All data or datagrams that travel in a network are simple binary numbers, impossible for a normal person to understand. What is done at this level is that these data are interpreted and rewritten so that applications and users can understand them.
Basically, it is the one that allows you to see an image that you download while browsing the Internet, even though for the network it was a handful of zeros and ones. In essence, it is a data translator .
Layer 7 (Application level)
Finally, there is the application level, which is what allows programs to use the information generated in the network for later execution.