Zero trust network architecture in Computer Networks - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the main principle of Zero Trust Network Architecture?

The main principle is 'never trust, always verify.' It means no user or device is trusted by default, even if inside the network. Every access request must be verified before granting access.

beginner

How does Zero Trust differ from traditional network security?

Traditional security trusts users and devices inside the network by default. Zero Trust assumes no trust anywhere and requires continuous verification for every access request.

intermediate

Name two key components of Zero Trust Network Architecture.

Two key components are: 1) Strong identity verification (like multi-factor authentication), and 2) Micro-segmentation, which limits access to only what is needed.

intermediate

Why is micro-segmentation important in Zero Trust?

Micro-segmentation divides the network into small zones to control access tightly. This limits the spread of attacks and ensures users only access what they need.

intermediate

What role does continuous monitoring play in Zero Trust?

Continuous monitoring checks user behavior and device health in real time to detect suspicious activity and enforce security policies dynamically.

What does Zero Trust Network Architecture assume about users and devices?

A They are never trusted by default

B They are trusted if inside the network

C They are trusted if they have a password

D They are trusted if connected via VPN

Zero Trust means no user or device is trusted automatically, even if inside the network.

Which of the following is a key feature of Zero Trust?

A Open network access

B Trust based on IP address

C Micro-segmentation

D No authentication needed

Micro-segmentation limits access zones to improve security in Zero Trust.

What is the purpose of continuous monitoring in Zero Trust?

A To allow all users access

B To disable security policies

C To reduce network speed

D To detect suspicious activity in real time

Continuous monitoring helps detect threats and enforce policies dynamically.

Which method strengthens identity verification in Zero Trust?

A Single password login

B Multi-factor authentication

C No login required

D IP address filtering only

Multi-factor authentication adds extra verification layers for security.

Zero Trust Network Architecture is best described as:

A Never trust, always verify

B Trust only external users

C Trust everyone inside the network

D Trust based on device type

The core idea is to never trust by default and always verify access requests.

Explain the core idea of Zero Trust Network Architecture and why it is important.

Think about how traditional networks trust users inside the network.

Describe how micro-segmentation helps improve security in a Zero Trust model.

Consider how breaking a network into smaller parts can control access.

Practice

1. What is the main principle of Zero Trust Network Architecture?

easy

A. Never trust, always verify every access request

B. Trust all devices inside the network by default

C. Allow unrestricted access to internal resources

D. Use a single password for all users

Solution

1. Step 1: Understand the core idea of Zero Trust

   Zero Trust means no implicit trust is given to any user or device, even inside the network.

2. Step 2: Identify the correct principle

   The principle is to verify every access request before allowing it.

3. Final Answer:

   Never trust, always verify every access request -> Option A

4. Quick Check:

   Zero Trust = Verify every request [OK]

Hint: Remember: Zero Trust means always verify, never trust [OK]

Common Mistakes:

• Assuming internal devices are trusted by default
• Thinking Zero Trust allows open access inside network
• Confusing Zero Trust with simple password policies

2. Which of the following is a correct feature of Zero Trust Network Architecture?

easy

A. Allow all devices to communicate freely once inside the network

B. Trust users based on their IP address alone

C. Use micro-segmentation to limit access to resources

D. Disable multi-factor authentication for ease of access

Solution

1. Step 1: Review Zero Trust features

   Zero Trust uses micro-segmentation to divide the network and limit access to only necessary parts.

2. Step 2: Identify the correct feature

   Micro-segmentation restricts lateral movement and improves security.

3. Final Answer:

   Use micro-segmentation to limit access to resources -> Option C

4. Quick Check:

   Micro-segmentation = Limited access [OK]

Hint: Micro-segmentation limits access inside network [OK]

Common Mistakes:

• Believing all devices are trusted inside network
• Ignoring multi-factor authentication importance
• Trusting users based only on IP addresses

3. Consider this scenario: A user tries to access a sensitive file in a Zero Trust network. The system checks the user's identity, device health, and location before granting access. What is the likely outcome if the device is found to be unpatched and vulnerable?

medium

A. Access is logged but allowed without restrictions

B. Access is granted because the user identity is verified

C. Access is granted but with limited permissions

D. Access is denied due to device health not meeting policy

Solution

1. Step 1: Understand Zero Trust access checks

   Zero Trust verifies multiple factors including device health before access is allowed.

2. Step 2: Apply policy to unpatched device

   An unpatched, vulnerable device fails health checks, so access is denied.

3. Final Answer:

   Access is denied due to device health not meeting policy -> Option D

4. Quick Check:

   Unhealthy device = Access denied [OK]

Hint: Unhealthy devices fail checks, access denied [OK]

Common Mistakes:

• Assuming identity verification alone grants access
• Thinking partial access is allowed despite vulnerabilities
• Ignoring device health in access decisions

4. A network administrator implements Zero Trust but notices users can access resources without verification. What is the most likely error in the setup?

medium

A. All devices are placed in a single trusted zone

B. Micro-segmentation is not properly configured

C. Multi-factor authentication is not enforced

D. User identities are verified but device health is ignored

Solution

1. Step 1: Analyze the symptom

   Users access resources without verification, meaning trust boundaries are missing.

2. Step 2: Identify configuration mistake

   Placing all devices in one trusted zone removes segmentation and verification.

3. Final Answer:

   All devices are placed in a single trusted zone -> Option A

4. Quick Check:

   Single trusted zone = No verification [OK]

Hint: No segmentation means no verification [OK]

Common Mistakes:

• Assuming MFA alone fixes all access issues
• Ignoring network segmentation importance
• Believing device health checks fix trust zone errors

5. A company wants to apply Zero Trust principles to secure remote work. Which combination of actions best supports this goal?

hard

A. Use VPN for all access, trust devices inside VPN, no further checks

B. Implement continuous user verification, device health checks, and micro-segmentation

C. Allow access based on user role only, ignore device security

D. Rely on firewall rules to block external threats, no internal controls

Solution

1. Step 1: Identify key Zero Trust actions for remote work

   Zero Trust requires continuous verification of user identity, device health, and limiting access via segmentation.

2. Step 2: Evaluate options for best fit

   Implement continuous user verification, device health checks, and micro-segmentation includes continuous verification, device checks, and micro-segmentation, covering core Zero Trust needs.

3. Final Answer:

   Implement continuous user verification, device health checks, and micro-segmentation -> Option B

4. Quick Check:

   Continuous checks + segmentation = Zero Trust [OK]

Hint: Combine verification, device checks, and segmentation [OK]

Common Mistakes:

• Trusting devices just because they use VPN
• Ignoring device security in access decisions
• Relying only on perimeter firewalls