What is FTPS Explicit SSL?
It is normal FTP, with some or all of the connection encrypted. Its much more flexible than implicit SSL. It can share the same port as FTP (21). When a user logs in, there FTP client asks the server if it supports Explicit SSL mode before it sends the user / pass. If the server does, then the connection is encrypted. The user and password is sent, and the connection continues with all future communication encrypted. The client can request that when files are transfered that the data connection either be encrypted or not. Implicit SSL always encrypts data transfers. Just like FTP, FTPS uses two connections. All the same info about FTP applies, except it is now encrypted. FTP explicit SSL runs on the same port 21 as FTP.
