Application layer protocol:

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Application layer Protocol

It is used for communication between applications
On different devices.
It plays a crucial role in enabling communication between applications and services over a network.

Key Points:

1. HTTP (Hypertext Transfer Protocol)

• Used for web communication.
• Facilitates data transfer between web servers and browsers.
• One of the most widely used protocols for internet applications.

1. FTP (File Transfer Protocol)

• Enables file transfers between devices over a network.
• Used for uploading, downloading, and managing files on servers.

1. SMTP (Simple Mail Transfer Protocol)

• Used for sending and receiving emails.
• Ensures email exchange between different network systems.
• Relies on TCP for reliable data transmission (no need for additional checksums).

1. DNS (Domain Name System)

• Translates human-readable domain names (e.g., google.com) into IP addresses.
• Allows users to access websites using easy-to-remember names instead of numerical IPs.

1. SSH (Secure Shell)

• Provides secure remote access to devices.
• Allows users to execute commands and transfer files securely over an encrypted connection.

1. POP3 (Post Office Protocol, Version 3)

• Used for retrieving emails from a remote server to a local device.
• Supports commands for logging in, fetching messages, and deleting emails.
• Commonly used in workplaces where users access emails from desktops.

Protocols:
Hypertext Transfer Protocol
It is used for
Web communication HTTP enables data transfer between Web Server

and browser. It is
one of the best
protocol in communication
applications.

• FTP
  Enables file transfer
  between devices over a
  network. FTP stand
  For file Transfer Protocols.
  which is used to
  Transfer the file
• SMTP (Simple Mail Transfer Protocol)
  Used for communication
  SMTP Faculties Sending

and receiving emails.
In emails, use these protocols. Design for the exchange of email between network systems.
No checksums needed because TCP provides a reliable byte stream.

DNS (Domain Name System)
Translate the domain name to IP addresses, enabling users to access the website using easy-to-remember domain names.

This protocol allows us to access the website easily. A domain name is an important part of a website.

SSH (secure shell)

Provide secure remote access to devices, allowing users to execute commands and transfer files securely.

Secure Sheet is related to file transfer security.

POP3
It is used to fetch email from a remote mailbox using POP3 (Post Office Protocol)
It has commands for the user to log in, log out, fetch, and delete messages. At many companies, users work at the desktop

Importance of Protocols

Protocols are essential tools that define how devices and services communicate. They enable different systems to interact efficiently, ensuring smooth data exchange across networks. Each protocol serves a specific purpose, making internet services like web browsing, email, and file transfers possible.

Protocols is basically
The tools which are
used for the
communication between
Devices and Services-
Through different
method using Protocol
We can access
to communicate.
The different devices
in different
ways-