You can use the gatherd.cf file (placed in the Data-Directory of a Gatherer) to control access to the Gatherer's database. A line that begins with Allow is followed by any number of domain or host names that are allowed to connect to the Gatherer. If the word all is used, then all hosts are matched. Deny is the opposite of Allow. The following example will only allow hosts in the cs.colorado.edu or usc.edu domain access the Gatherer's database:
Allow cs.colorado.edu usc.edu
Deny all