How to secure file transfers with SFTP vs FTP

Short answer

FTP transmits files and credentials in plaintext. SFTP (SSH File Transfer Protocol) encrypts both authentication and data over an SSH tunnel, making it the secure choice for file transfers.

Key differences

• Security: FTP sends passwords and files unencrypted. SFTP encrypts everything.
• Protocol basis: FTP uses separate command and data channels. SFTP operates over a single SSH connection on port 22.
• Firewall friendliness: SFTP requires only one port. FTP needs multiple ports and passive mode configuration.
• Integrity: SFTP provides built-in mechanisms to verify file integrity.

When to use each

• Use FTP never on public networks; only in isolated legacy scenarios.
• Use SFTP for all production file transfers, automated backups, and remote administration.

Why it matters

Using FTP exposes credentials and sensitive data to trivial packet sniffing. SFTP protects intellectual property, customer data, and system credentials during transit.