The Connection Sequence

A request for connection to an FTP site comes from user actions in either the Classic or Explorer interface, or by one of the Progress WS_FTP Professional utilities such as Find or Synchronize. Sometimes, additional connections are requested by the Transfer Manager to resume or to speed up transfers. All connections are created by the CreateConnection function in the Progress WS_FTP Professional API.

The connection sequence consists of two stages.

• Stage 1: Establish the connection with either the firewall or the FTP server.
• Stage 2: Send commands to log in and authorize the connected user. It is during this stage that the commands in a FireScript are executed.

The first stage works the same whether Progress WS_FTP Professional is using a FireScript or using one of its internal firewall types. Before executing the script, Progress WS_FTP Professional checks the fwsc section for the list of fields marked as required and preask. If any are missing, it displays the login dialog. If the user fills in all required information and presses Connect, Progress WS_FTP Professional then checks the connectto field. Depending on this field, it will either establish a connection to the firewall's IP address and port, or to the FTP server's IP address and port. If this field is not present, Progress WS_FTP Professional defaults to the IP address of the firewall, if present.

After the connection is established successfully, and a valid socket is opened, Progress WS_FTP Professional calls the FireScript executive to execute the FireScript. If the Firelogs in correctly and returns success, the CreateConnection function returns the authorized connection to the caller.