Perimeter Focus or Deperimeterized?

About this interactive

The perimeter is the outside of the network: every entry point where someone could get in. For a long time, security focused there. Picture an onion: as long as the outer layer, mostly the firewall, held up, the center was considered safe. That is not enough. Firewalls and access points have vulnerabilities, and a big way in is through the users who already have access: they open attachments and click links that bring trouble inside. So the attack surface is more like an artichoke, with many surfaces to creep in through. Deperimeterization is a mindset, not the removal of anything. Keep your firewalls; they add security. But plan as if they were not there: protect the resources themselves, and check users and devices inside with policy-driven access control such as NAC and zero trust. It reinforces defense in depth. To sort a card, ask whether the decision depends on the edge holding, or protects what is inside on its own.

What you'll learn

Tell a security decision that relies on the network perimeter from one that follows the deperimeterized mindset of protecting resources as if the edge were not there
Explain that deperimeterization keeps the firewall but no longer relies on it, because users inside the network are a main way in

Aligned to

CompTIA Security+

3.2 Given a scenario, apply security principles to secure enterprise infrastructure.

1.2 Summarize fundamental security concepts.

Key terms

Deperimeterization: A security mindset that shifts focus away from perimeter-based defenses toward holistic, layered protection of internal network resources and assets.
Defense-in-Depth: Defense-in-Depth is a security architecture strategy that layers multiple independent controls across technical, physical, and administrative domains so that the failure of any single control does not result in a complete security breach.
Attack Surface: The total set of points in a system where an unauthorized user can attempt to enter or extract data.
Firewall: A network security device that monitors and controls incoming and outgoing traffic based on predefined security rules.

Topics

Interactive Streak Sort

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