A protocol in computing refers to a set of predefined rules for the purpose of standardizing the exchange of information in computing activities. By following the same protocol, it is guaranteed that there will be compatibility between the devices at the different points of a computer system.
Because they are information exchange between computers, they are called communication protocols. A protocol defines in detail the format for the exchange of information and must be agreed by all parties involved.
Otherwise, there could be an incompatibility in standards that would be equivalent to two interlocutors communicating in different languages.
Properties
Although the protocols can be different from each other depending on their use, development and age, in general they share some basic elements, such as the processes used to detect connection.
These include how to identify other users on the network, handshaking or greeting between network elements, what to do in case of incomplete messages or loss of connection, and the standardization of security in communication using authentication and / or encryption.
For each level in the communication process there is a protocol layer dedicated to a specific action.
The lowest level are the physical layer, the data link and the network layer, which are responsible for the transport of data between one device and another.
It is there that the information is converted into digital bits and moves through cables or the air, in the case of wireless connections.
At a higher and more abstract level are application layers, in which devices agree to use certain methods to encrypt information, to connect with each other, and to define the type of messages that are transmitted.
Examples
CAT5, CAT6 and fiber optics are some of the connection types at the physical level of the connection.
Ethernet and Gigabit Ethernet, along with IPv4 and IPv6, are the most widely used protocols for data link and network respectively. Data transport is commonly done through the TCP and UDP protocols.
At the application level the most used protocols are Telnet, SSH, POP3, IMAP and HTTP. These are in charge of encrypting and transmitting the information that will be sent through the transport layer, and then to the data link layer.
The 9 most used protocols
1-
It is perhaps the best known and most used protocol for communications on the Internet. Its acronym stands for HyperText Transfer Protocol.
This is responsible for the transfer of hypertext (text with clickable links) that has been used in web browsers since the early nineties.
2-
It is an extension of HTTP that encrypts data end-to-end, so that only the server and the browser can decrypt the information that passes through the protocol.
3- FTP
It is the file transfer protocol (File Transfer Protocol) and is used to send and receive files over the network.
4- Telnet
It is used to access remote computers.
5- SSH
It allows the same as Telnet, but with much more capacity.
6- SFTP
It stands for Extensible Messaging and Presence Protocol, and it continues to be used in instant messaging applications such as Google Talk and Facebook Messenger.
References
- Wikipedia - Communications protocol en.wikipedia.org
- What does protocol, www, http mean? uefsfainformaticavaca.blogspot.com
- Protocol Dictionary - Network Protocol Suite Directory and Index javvin.com
- Lifewire - Network Protocols lifewire.com
- Technopedia - Network Protocols ceilingpedia.com