SFTP and SCP: Secure File Transfer Protocols

SFTP (SSH File Transfer Protocol) and SCP (Secure Copy Protocol) are both secure file transfer protocols that operate as subsystems of SSH-2 (Secure Shell version 2). These protocols provide encrypted and authenticated methods for transferring files between systems.

SFTP (SSH File Transfer Protocol)

SFTP is a robust and versatile protocol that offers secure file transfer capabilities:

Key Features:

SCP (Secure Copy Protocol)

SCP is another secure file transfer protocol that, like SFTP, operates as an SSH-2 subsystem:

Comparison to SFTP:

Poison pill: in order to fill the functionality gap between SFTP and SCP, some SCP clients attempt to use a parallel SSH-2 Shell to perform some of the operations the SCP protocol lacks, but in doing so they create a potential side-channel for attacks. If all you need are secure file-transfers, and SCP is requesting to perform Shell operations, the safest choice is to drop SCP altogether and switch to SFTP. Do not allow Shell just because SCP may ask for it, unless you know exactly how to keep it safe.

SSH-2 Subsystems

It's important to note that SFTP and SCP are not the only subsystems of SSH-2. The SSH-2 protocol is a versatile framework that supports various subsystems:

  1. File Transfer: SFTP and SCP.
  2. Remote Command Execution: Allows running individual commands on the remote system.
  3. Shell Access: Provides a full interactive shell session on the remote machine.

This flexibility makes SSH-2 a powerful tool for secure remote system management and file transfer, but - as all powerful tools - it requires careful configuration from a knowledgeable administrator.

Security Considerations

Both SFTP and SCP offer significant security advantages over traditional, unencrypted file-transfer protocols:

Choosing Between SFTP and SCP

When deciding between SFTP and SCP, consider:


Revision #1
Created 25 November 2024 23:32:07 by DevTeam
Updated 25 November 2024 23:45:04 by DevTeam