Which command serves as a second utility for transferring files securely over a network?

The command that serves as a second utility for transferring files securely over a network is sftp. This stands for Secure File Transfer Protocol, which is a secure version of the traditional File Transfer Protocol (FTP). It allows for secure file transfer over a secure shell (SSH) connection, integrating file transfer capabilities with the security features provided by SSH, such as encryption and authentication.

sftp operates interactively, similar to FTP, but benefits from the confidentiality and integrity protections of SSH. This means that data transferred using sftp is encrypted, making it secure against eavesdropping and man-in-the-middle attacks.

While other options like rsync and scp also support secure file transfers, the question specifically asks for a second utility, suggesting that sftp is distinct from these methods yet still fulfills the criteria of secure file transfer. Rsync is typically used for synchronization and can use SSH for secure transfers, while scp is directly based on SSH for transferring files but is not as feature-rich as sftp regarding session management and interactive usage. Tar, on the other hand, is primarily a tool for archiving files and does not handle secure transfers on its own.