Perimeter network
DMZ
Primary/secondary
Master/slave
Host/client
Master/slave
Become unresponsive
Hang
Blocklist
Blacklist
Deny list
Blacklist
Unapproved list
Blacklist
Allow list
Whitelist
Approved list
Whitelist
Foreign adversary
Specific countries considered enemies of a country
Built-in
Native
Default
Native
Inherent
Native
Standard
Native
Unknown environment testing
Black-box testing
Known environment testing
White-box testing
Partially known environment testing
Gray-box testing
Unauthorized
Black hat
Authorized
White hat
Semi-authorized
Gray hat
Sinkhole
Black hole
Process vacuum
Black hole
Blank screen
Black screen
Power loss
Blackout