LCE: The failure of operating systems and how we can fix it

Putting my system admin hat on I want both border *and* host security. There is a lot that makes sense to block at borders because outsiders have no business using them. Servers on the safe side of firewalls often have to have more services configured and are therefore less secure.

If both a border firewall blocks some attack traffic then a security bug on an internal system is not immediately fatal and there is time to fix it before the border firewall's security is breached. If that has not happened that implies nobody worthwhile has tried or you can't detect security breaches.

In an ideal world there would be no need for security because nobody would even think of doing a bad dead. The world has never been that way.