have you ever heard about network protocols? what are they and what types do they have? well, as always, we first go through some basic concepts you must know to learn about network protocols and then discuss the main subject(common network protocols). here are some must-known concepts to start learning about protocols:
Open Systems Interconnection model (OSI model) which is known as “7 layers OSI” is a conceptual model that characterizes and standardizes the communication functions of a computing or telecommunication system regardless of its underlying internal structure and technology.
Generally, all networks and telecommunications have 7 aspects (or layers):
- Physical Layer
- Data Link Layer
- Network Layer
- Transport Layer
- Session Layer
- Presentation Layer
- Application Layer
Do not worry! Because for understanding network protocols you don’t have to be familiar with all of these 7 layers (which are not things, but only concepts).
We just wanted you to know that OSI model is showing different aspects (or better to say “tasks”) of a network that are involved in the whole function of a network.
Layer in computer networks:
In a network, computers have different tasks to do, Like: data transmission, packetization, digitization, routing, etc.
Layering is splitting these different kinds of tasks into different distinct functions or “layers”.
Now, what are network protocols?
Network protocols are the standards (agreed ways) which define the method of data transmission in a computer network.
Protocols are available for different levels in OSI model and define that level’s functionality.
Protocol that work together in order to provide 1 or more layers are known as a protocol stack or protocol suite.
There are several types (groups) of protocols based on their goal in a network:
Network communication protocols:
Which contains basic data transmission and communication protocols. Like: TCP/IP and HTTP.
Network security protocols:
Which are about protocols that implement security over network communications, Like; HTTPs, SSL, SFTP
Network management protocols:
Which provide network maintenance and governance. Like: SNMP, ICMP.
Now we are going to discuss about some of the most common protocols that are used in most networks to do different tasks in a network or better said: to reach the goal of different layers of a network.
Note: for each tasks you may use various protocols together to reach a goal and do a task in a network; remember that each groups of protocols that work together for one aim, are called: protocol stacks.
enables data transportation between physical locations on Ethernet cable. In this protocol data will pass in Ethernet packets. (goal: physical layer and data link layer)
Internet Protocol (IP):
all of all kinds of protocols’ data packets (except for ARP and RARP) will packaged in to an IP data packet.
This protocol (IP), enables systems in a network to address and manage sent data packets to computers via software. (network layer)
Serial line IP (SLIP):
Which aims to encapsulate data for serial lines.
Internet control message protocol (ICMP):
Enables error reporting to help manage the process of sending data between computers. (network layer)
Point to point protocol (PPP): more improved way of encapsulating serial line data than SLIP.
Address resolution protocol (ARP):
For packaging IP packets into Ethernet packages by determining Ethernet (hardware) address from a specific IP number. (network layer)
File Transfer Protocol (FTP):
Requires login to allow files to be transferred between two computers.
At the end of the day, each protocol’s packets will be wrapped in an Ethernet, SLIP, or ppp packets to be able to be sent through an Ethernet cable.
However, some protocol’s packets need to be wrapped multiple times before being sent.
For instance, FTP data will be wrapped in TCP packet and then in an IP packet and then in a link layer protocol’s layer packet (usually Ethernet), and then be sent.