SFTP
acronymnetworkingsecurity
Stands for: SSH File Transfer Protocol
A file-transfer protocol that runs securely over SSH.
SSH File Transfer Protocol runs inside an SSH session, so it inherits SSH's encryption and authentication. Despite the similar name it shares nothing with FTP or FTPS.
SFTP is a file transfer subsystem of SSH, sharing nothing with FTP but three letters. It uses one connection on one port, inherits SSH's authentication including keys, and is encrypted throughout.
That single-connection design is why it works through firewalls and NAT where FTP does not, and why it is the correct default. The operational care it needs is around authorization rather than transport: an SFTP account is usually a shell account unless deliberately restricted, so chroot or a forced subsystem is what keeps a file transfer user from becoming a shell user. Key management is the other half, and an SFTP integration whose key has no expiry and no owner is a common audit finding.
Also known as: sftp