question on

[Clarence <c5666305@hkstar.com>]

Hello,

For the couple of days, I spent most of the time to study the setup of
VPN, X509... for the infrastructure (LAN).  However, I have one question
in my mind that confuse me very much.  Let me present it with the diagram
list below.

internet <--> openbsd-gw <--> internal LAN (wireless / wired)

The question is like that how can the sys admin guard the illegal user
from the ineternal LAN to use the facilities of the openbsd-gw.  He may
know the IP of the openbsd-gw, DNS server.  For example, he/she may use
a laptop with a wireless LAN and setup all necessary setting to use the
facilites of the GW.  How can the sys admin control it.  If it is stupid
question, please forget me.    Thanks.

Clarence