Which protocol is more secure for remote administration of Cisco devices?

The most secure protocol for remote administration of Cisco devices is SSH (Secure Shell). SSH provides encryption for data transmitted over the network, which secures the communication between the client and the server from eavesdropping and man-in-the-middle attacks. It also authenticates the user and the server, ensuring that both parties involved in the communication are legitimate.

In contrast, other options do not offer the same level of security. Telnet transmits data in plain text, making it vulnerable to interception and unauthorized access. HTTP is also an unsecured protocol, primarily used for web traffic without encryption, which leaves it open to similar risks as Telnet. FTP (File Transfer Protocol) is designed for transferring files and, like Telnet and HTTP, does not encrypt the connection, making it susceptible to security threats.

Thus, SSH's inherent design for encrypted connections makes it the preferred and more secure choice for remote administration tasks on Cisco devices.