SSL vs Implicit SSL

WS_FTP uses two types or 'flavors' of the SSL protocol. Explicit SSL and Implicit SSL. The encryption strength and stability is virtually the same. The only difference lies in the way the client communicates with an FTP server during connection negotiations, and the port that the server is 'listening' on.

  • Explicit SSL - Client starts the connection with a connection 'in the clear' and then attempts to secure the connection before sending the username and password.
  • Implicit SSL - In this version, the client sends all negotiations to the server in a secure manner. Implicit SSL connections use port 990, so any attempt at connecting to a server that is not configured for Implicit SSL will fail.