What protocol is Telnet?

Telnet is a simple text-based network protocol used to access remote computers and terminals through "TCP/IP" networks; telnet provides users with a two-way interactive text communication system that uses Virtual terminal connection exceeding 8 bytes.

Telnet is a simple text-based network protocol used to access remote computers and terminals over TCP/IP networks such as the Internet, but is also used For initial setup of equipment, such as network hardware. [Video Tutorial Recommendation: TCP/IP Tutorial]

Telnet is designed for remote server access, management and client/server architecture, implemented through a dedicated program that provides remote computer /Connection between server and host. After providing the correct login and login credentials, the user can access the privileged functions of the remote system. Additionally, Telnet commands can be executed on supported client or server devices.

How does Telnet work?

telnet provides users with a two-way interactive text communication system that uses virtual terminal connections over 8 bytes. Over Transmission Control Protocol (TCP), user data and telnet control information are spread in-band. Typically, telnet is used to remotely execute functions on a terminal.

Users connect to the server using the telnet protocol, which means telnet is entered into the command prompt following the following syntax: telnet hostname port. The user then executes commands on the server by using specific telnet commands in the telnet prompt. To end the session and log out, the user uses the telnet end telnet command.

What are the security risks of using Telnet?

Telnet only sends and receives data in plain text, and has no specific security mechanism and no encryption measures. This means that whenever you connect to a Telnet server, your personal data such as username and password will be transmitted in clear text. Anyone who knows how to use an application to sniff a network connection (ie: a hacker) will see all data being transferred.

As a result, Telnet has been replaced by Secure Shell (SSH) in many applications and services.

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