Supported Transfer Protocols

As of version 4.0, WinSCP supports three transfer protocols, SFTP, FTP and SCP. Currently, many servers support all three protocols. Each has its advantages and disadvantages, while FTP has one big disadvantage, being insecure. This document contains a comparison to help you to decide which is most appropriate for your needs. The comparison describes both features that are characteristic to the specific protocol as-is, and features that are caused by the implementation of the protocol in WinSCP.

The default mode of operation is to use SFTP and fall back to SCP. Select your preferred protocol on Login dialog.

SFTP (SSH File Transfer Protocol)
SCP (Secure Copy Protocol)
FTP (File Transfer Protocol)
Protocol Comparison

SFTP (SSH File Transfer Protocol)

Despite SSH in its name, it is designed to work over any reliable data stream, but WinSCP supports only operation over SSH, which is also by far its most common usage.

Being operated over SSH, it is secure protocol. In its basic functionally it is similar to old FTP, while having better designed advanced functionality. Unfortunately not all SFTP server implementations take advantage of the advanced features, yet.

Especially in its later versions (from 4 upwards), it is more platform independent, compared to both FTP and SCP.

Unlike SCP, for connection with an SFTP server you do not need access to shell (although some implementations may still require that).

SCP (Secure Copy Protocol)

SCP is mostly used with SSH-1. SCP is an older protocol but almost universally supported on Unix-like platforms as part of an SSH protocol suite. It is rarely supported on other platforms. SCP is a descendant of the ancient “rcp.”

The SCP protocol allows only file transfers in both directions. WinSCP is able to offer other features, implemented using common shell commands like cd, ls, pwd, rm, ln, etc. For this, WinSCP—unlike command-line SCP clients (which allow only file transfers)—requires full shell access and permission to execute other commands in addition to scp (see requirements). For access to non-UNIX servers it is necessary that the server have at least a UNIX-like shell.

FTP (File Transfer Protocol)

FTP, being the oldest of the three, is most widespread transfer protocol of nowadays. It is inherently insecure, sending all data (including passwords) unencrypted. Although there exists secure variants (FTP over SSL), they are not supported by WinSCP. Functionally it is inferior to SFTP. Also it is less platform independent than later versions of SFTP, mainly in respect to directory listing.