SPAMfighter Mail Gateway needs to have access to the internet, but SPAMfighter Mail Gateway only needs access to UDP/2409 to servers.backend.spamfighter.com and TCP/2409 to https//login.spamfighter.com.
To be able to receive automatic updates access to TCP/80 to https://www.spamfighter.com is needed, but not an absolute requirement.
This makes it possible for the system administrator to secure the network by being able to close all other connections other than the ones listed.