Which Principle Is It? — TechKnowSurge

About this interactive

A principle is a rule that guides decisions, and this module's are the guidelines for architecting a secure network. Five of them are easy to confuse, because one design decision can look like several. Least functionality is about the system: install and run only what its job needs. Least privilege is about access: give each user, application or system the least rights that let it do its job. Segmentation is about separation: divide data, networks, keys, databases, buildings and duties into parts, so a compromise in one part stays there. Defense in depth is about layers: put more than one safeguard between an attacker and an asset, inside the perimeter as well as at it, so when one fails another holds. Zero trust is about verification: never trust because of location or an earlier check; verify each request. Ask what the decision changes. Removes software: least functionality. Narrows one identity's rights: least privilege. Splits one thing into separate parts: segmentation. Adds another barrier behind an existing one: defense in depth. Replaces a one-time or location-based trust with a check on each request: zero trust.

What you'll learn

Identify which security architecting principle a design decision applies: least functionality, least privilege, segmentation, defense in depth or zero trust
Tell apart principles that are easily confused: removing a function (least functionality) from narrowing access (least privilege), separating things (segmentation) from adding layers (defense in depth), and layering from verifying every request (zero trust)

Aligned to

CompTIA Security+

1.2 Summarize fundamental security concepts.

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

2.5 Explain the purpose of mitigation techniques used to secure the enterprise.

Key terms

Least Functionality: A security principle that requires systems to be configured with only the essential capabilities needed to perform their intended function, reducing exposure to potential threats.
Least Privilege: A security principle that grants users and systems only the minimum access rights needed to perform their functions.
Network Segmentation: The practice of dividing a network into smaller segments to improve performance and limit the spread of security threats.
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.
Zero Trust: A security model that assumes no user or device is trusted by default and requires continuous verification.

Topics

Security Principles Least Functionality Least Privilege Network Segmentation Defense In Depth Zero Trust Interactive Categorize

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