How firewalls, UTM, NGFW, SSE, and SASE evolved to meet modern threats

Network security architectures evolve when reality breaks old assumptions.

For a long time, organizations assumed that users sat inside offices, applications lived in data centers, and the internet was something accessed from a controlled perimeter. Security systems were designed around that world.

Over the last two decades, that world slowly disappeared. Each new architecture emerged not because the previous one was “bad,” but because it could no longer see or control what mattered most.