Which protocol is used for Unix and Linux credentials?

The protocol used for Unix and Linux credentials is SSH, which stands for Secure Shell. SSH is a cryptographic network protocol that provides a secure channel over an unsecured network in a client-server architecture. It is commonly used for securely accessing and managing devices and servers remotely.

SSH is designed to facilitate secure communication by encrypting data that is transmitted between the client and server, which is essential when handling sensitive authentication credentials. This protocol allows for the use of password-based or key-based authentication, making it a versatile choice for securely managing Unix and Linux systems.

In contrast, other options such as FTP, TCP/IP, and HTTP are not specifically geared towards the secure transmission of credentials. While FTP is often used for file transfers, it lacks encryption, making it unsuitable for sensitive data. TCP/IP is a fundamental suite of protocols that supports various types of communication on the internet but does not inherently provide security features for credential management. HTTP is the protocol used for transferring web pages, and while it can be secured with HTTPS, it does not specifically handle credentials in the manner that SSH does. Thus, SSH stands out as the appropriate choice for managing Unix and Linux credentials securely.