INTRODUCTION TO NETWORK SECURITY

2 THREATS AND VULNURABILITIES

NETWORK SECURITY DEVICES AND TECHNOLOGIES

NETWORK TRAFFIC ANALYSIS

CRYPTOGRAPHY AND NETWORK SECURITY

NETWORK SECURITY ANALYSIS AND FORENSIC

SECURING WIRELESS NETWORKS

ADVANCED TOPICS IN NETWORK SECURITY

Implementing a zero-trust network model

ZERO TRUST NETWORK MODEL 

The Zero Trust Network (ZTN) model is a security concept and architecture that assumes no trust by default, whether inside or outside the network. 

This means that every user, device, and application must continuously verify and authenticate before being granted access to any resource or system, regardless of their location within or outside the organization's perimeter.

The key idea behind Zero Trust is that traditional security models (e.g., perimeter-based security) are no longer effective, especially with the increase in remote work, cloud environments, and mobile devices. 

The Zero Trust model emphasizes constant validation, access control, and verification at every layer of the network.

Principles of the Zero Trust Model:

  1. Never Trust, Always Verify:

Trust no entity (user, device, application) by default. Every access request is treated as if it originates from an untrusted network.

  1. Least Privilege Access:

Grant users and devices the minimum access necessary to perform their job functions.

  1. Micro-Segmentation:

Divide the network into smaller, isolated segments or "zones" that restrict lateral movement of attackers.

  1. Identity and Access Management (IAM):

Strong identity verification is essential. Every user, device, or application must be authenticated and authorized before accessing any resource..

  1. Continuous Monitoring and Analytics:

Continuously monitor user and device behavior, network traffic, and access patterns to detect any anomalies or potential threats in real-time.

  1. Data Protection:

Ensure that sensitive data is always protected, both in transit and at rest, by enforcing strict access policies and encryption.

STEPS TO ZERO TRUST IMPLEMENTATION


 


 

  1. Define the Attack Surface
    The first step in implementing a Zero Trust model is to define your attack surface. 

This means identifying the areas you need to protect to avoid feeling overwhelmed when implementing security policies and deploying tools across your entire network. Focus on safeguarding your most valuable digital assets.

Areas at Risk of Attack

  • Sensitive Data: This includes customer and employee information, as well as proprietary data that must be kept secure.
  • Critical Applications: These are essential applications that support your key business processes.
  • Physical Assets: This category includes devices such as point-of-sale (PoS) terminals, IoT devices, and medical equipment.

 

  1. Implement Controls Around Network Traffic
    The flow of traffic through your network depends on the relationships between various systems. For instance, many systems need access to a database containing sensitive information. Requests don’t simply enter the system; they must be routed through secure databases and architecture. 

 

  1. Architect a Zero Trust Network
    Design your Zero Trust network , with a next-generation firewall (NGFW) to segment portions of your network. Also implement multi-factor authentication (MFA) to ensure users are thoroughly vetted before gaining access to critical systems.

 

  1. Create a Zero Trust Policy
    Once your network is architected, design your Zero Trust policies. This process is most effective when using the Kipling Method—asking who, what, when, where, why, and how for every user, device, and network that seeks access.
  2. Monitor Your Network
    Regular monitoring of your network can alert you to potential security issues and provide insights to optimize network performance while maintaining security.

How to Monitor Your Network

  • Reports: Regular reports can help flag abnormal behavior. Analyzing these reports will also allow you to assess how your Zero Trust implementation affects system performance and identify areas for improvement.
  • Analytics: Using analytics to examine system-generated data can provide insights on network traffic, component performance, and user behavior patterns.
  • Logs: Logs provide a permanent, time-stamped record of activities on your network. These can be analyzed manually or through automated tools, like machine-learning algorithms, to detect anomalies and patterns.