Which protocol is primarily used for secure remote login to network devices?

The protocol that is primarily used for secure remote login to network devices is SSH, which stands for Secure Shell. SSH provides a secure channel over an unsecured network by using strong encryption to protect the data being transmitted. This is particularly important for maintaining confidentiality and integrity during remote sessions, as it prevents eavesdropping and man-in-the-middle attacks that could compromise sensitive information.

SSH not only facilitates remote login but also allows for secure file transfers and command execution on remote machines. Its usage has become the standard for secure administrative access to network devices like routers and switches, as well as servers. In contrast, protocols such as HTTP, FTP, and TFTP do not provide the same level of security, making them unsuitable for secure remote administration. HTTP is designed for web traffic and does not encrypt data, while FTP and TFTP, being file transfer protocols, also transmit data in plaintext without any encryption, making them vulnerable to interception.