SFTP, or Secure File Transfer Protocol, is a network protocol that provides secure file access, transfer, and management capabilities over SSH (Secure Shell) connections. Unlike FTP, which operates over plain text channels, SFTP encrypts both commands and data using SSH to ensure confidentiality and integrity during file transfers.
SFTP works by establishing an SSH session between a client and a server. Once authenticated, the client can perform file operations such as upload, download, rename, delete, and manage directory structures securely over the SSH connection. SFTP clients and servers typically authenticate using username/password credentials or SSH key pairs for enhanced security.
The protocol used for SFTP is SSH, specifically the SSH File Transfer Protocol (SFTP). SSH provides a secure channel over an unsecured network, encrypting data to prevent unauthorized access and interception. SFTP utilizes this secure channel to transfer files securely between the client and server, ensuring data protection.
The main difference between FTP and SFTP lies in security. FTP sends data in plaintext, making it vulnerable to interception and unauthorized access. In contrast, SFTP encrypts both commands and data, providing a higher level of security suitable for sensitive file transfers. SFTP is also firewall-friendly, as it typically uses a single port (usually TCP port 22) for both command and data transmission, simplifying network configuration and enhancing security.
Examples of Secure File Transfer Protocol (SFTP) implementations include OpenSSH, which includes an SFTP server and client functionality, and commercial SFTP server software such as Bitvise SSH Server, Titan SFTP Server, and SSH.com’s Tectia SSH Server. These tools provide robust encryption, authentication mechanisms, and management features for secure file transfers in various organizational settings.