SFTP support is provided by the most widely used SSH server library for Java.  There are no known incompatible SFTP clients.  SCP is also supported on the same port.

[Public / Private| UserManagerRestrictionsSSH] key authentication is supported too.  The ciphers can be customized to prevent wasted CPU usage from inefficient ciphers.

By default, there is an Idle Timeout set to 300 sec (5 min). Go to the SSH tab to change.