Apple IP (AppleShare IP) Gateway - Manual (Page 65)

10 Click OK.
The dialog box closes. When you restart the gateway, your changes will be
in effect.
Preventing unauthorized access by IP computers
The Apple IP Gateway works in both directions. Just as clients on the
AppleTalk side have access to the IP network, IP computers have access to
Macintosh computers on AppleTalk networks. Restricting this access cannot
be done from the AppleTalk side. It can, however, be accomplished with most
IP routers. See your IP router documentation to arrive at a suitable method.
Establishing gateway security 57