ZTNA fills this need by offering the granular, context-aware access for business-critical applications, without having to expose other services to possible attackers. The ZTNA model was coined by Gartner to help eliminate the granting of excessive trust to employers, contractors, and other users who only need very limited access. The model expresses the concept that nothing is to be trusted until proven trustworthy, and more importantly that trust must be reauthenticated whenever anything about the connection (location, context, IP address, etc.) changes.