Reference: Configure Services Dialog
This field specifies the number of additional permanent connections (as opposed to switched connections) configured for incoming calls from remote Beyond FTP clients and servers. While all permanent connections can be specified in the address book, this field provides a shorthand mechanism for assigning a group of connections to incoming, permanent calls. Permanent connections are never dropped. The total number of connections available to the Beyond FTP server is the sum of the switched and permanent connections, where the permanent connections are those explicitly configured in the address book, and those specified by this field. All permanent connections take place on the port that is 1 greater than the value specified by the service port entry.
This value has meaning only for the Server version of Beyond FTP. The Client version is limited to just two connections.