Zero-trust networks

Back in the days before cloud services were commonly used, enterprises only had networks on their own premises. Back in the 1990s and early 2000s, the network security paradigm was all about perimeters.

Different network segments could have different levels of security, but the internal network and all of its segments were contained within a heavily guarded perimeter. Sometimes, external traffic would be allowed into the internal network, but it’d have to pass a vector for authentication and authorization. But once that perimeter was cleared, the user could travel within the internal network without having their credentials checked again. All users were either trusted or distrusted, and existing inside the perimeter meant automatic trust. Think of a country with a heavily guarded border, but little police presence inside of the country.

The old perimeter model of network security has been obsolete for many years now. There are multiple reasons why.

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