In this section of the course,
we are going to discuss Zero Trust Design.
The Zero Trust Design section of the course
focuses on Domain 2: Security Architecture,
specifically, objective 2.6
which states that given a scenario,
you must be able to integrate
Zero Trust concepts into system architecture design.
Zero trust is used because traditional security models,
which rely on perimeter defense,
no longer effectively address
today's complex threat landscape
and diverse network environments.
Zero trust ensures that every user and device,
regardless of their location, is continuously validated
and granted network access
based on strict context-aware policies.
Furthermore, zero trust emphasizes
the need to carefully manage interactions,
control resources, and integrate
various security technologies
to reduce vulnerabilities.
As we go through this section,
we will cover many topics related to Zero Trust Design,
including Security Boundaries,
Virtual Private Network Architecture,
Segmentation, Deperimeterization, Access Management,
Application Programming Interface Integration
and Validation, and Asset Control.
First, we will look at Security Boundaries.
Security boundaries are defined
by strict access controls and continuous verification,
rather than physical or network perimeters.
The implementation of security boundaries
enables the monitoring and validation
of every cross network interaction.
Security boundary concepts include system components,
data perimeters, and secure zones.
System components are individual elements,
such as servers, workstations, and applications
that make up the information technology infrastructure
and must be secured individually
within a zero trust framework.
Data perimeters refer to the boundaries
around sensitive information
where access is controlled and monitored
to prevent unauthorized access,
regardless of where the data resides.
Secure zones are segmented areas
within the network where access is tightly controlled
and continuously verified.
Secure zones provide a higher level of protection
for critical assets and data.
For example, in a zero trust model,
a company might create secure zones
within their network for sensitive financial systems,
applying strict access controls
and continuous monitoring to each system component
and data perimeter to ensure that
only authorized users are able to access critical
and sensitive resources.
Next, we will explore Virtual Private Network Architecture.
Virtual private network architecture
extends access controls
beyond traditional network boundaries.
There are a variety of virtual private network models,
such as a client-to-server or a site-to-site,
and an always-on virtual private network.
A client-server virtual private network
establishes a secure tunnel
between an individual device,
known as a client, and a central server.
This ensures encrypted communication
and network access for remote users.
A site-to-site virtual private network
connects entire networks securely,
which allows branch offices
or remote sites to communicate with a central network
as part of the same logical network.
An always-on virtual private network
is a virtual private network connection
that is always active,
so it provides continuous secure access
and enforces access policies consistently,
regardless of the user's location.
For example, in a zero trust architecture,
an organization may use a client server
virtual private network
to secure remote employees' connections
to internal applications,
while utilizing a site-to-site virtual private network
to maintain secure connections
between different branch office locations.
After that, we will look at Segmentation.
Segmentation is dividing a network
into distinct zones or segments to control
and limit access between different areas.
This enhances security
and reduces the network attack surface.
A specific type of segmentation
known as microsegmentation takes this approach further
by creating even smaller,
more granular segments within each larger network segment.
Microsegmentation can then provide
detailed control over network traffic
and access at the individual workload level.
For example, in a zero trust model,
an organization might use segmentation
to isolate sensitive financial systems
from general user areas and apply microsegmentation
within the financial segment
to control access to specific applications
and data based on user roles and attributes.
Next, we will explore Deperimeterization.
Deperimeterization refers to the shift away
from relying solely on traditional flat-network perimeters
and instead focusing on verifying
and securing every user and device,
regardless of their location within the network.
The concept of deperimeterization acknowledges
that a network boundary is no longer defined
by a geographic location,
since users, clients and vendors often need access
to the network infrastructure from remote location.
Deperimeterization concepts
include Software-Defined Networking,
Software-Defined Wide Area Network,
and a Secure Access Service Edge.
Let's take a moment to discuss each of these concepts.
Software-Defined Networking allows
for centralized control and management
of network traffic implemented
across a large enterprise network.
Software-Defined Networking
also allows the enforcement
of security policies across the entire network,
regardless of physical boundaries.
Software-Defined Wide Area Network
extends the Software-Defined Networking Concept
by optimizing and securing connectivity
across large geographical areas,
such as between branch offices and remote sites.
Secure Access Service Edge integrates security
and networking functions into a unified cloud-based service.
This ensures access and continuous monitoring of users
and data as they move across cloud-based
and on-premise network boundaries.
For example, an organization might use
Software-Defined Wide Area Network to connect remote
and geographically dispersed branch offices,
while using Software Defined Networking
to manage and enforced access controls
across the logical network,
and they might concurrently use Secure Access Service Edge
to provide comprehensive security and monitoring
for users accessing resources
from any location via cloud and non-cloud based connection.
Following that, we will look at Access Management.
Access management is used to continuously verify
and control user and device access
to resources based on policies
and contextual factors.
This is more secure than systems
that assume trust based on a network location.
Access management concepts
include subject-object relationships,
continuous authentication,
and context-based reauthentication.
Let's take a moment to talk about each of these concepts.
Defining Subject-object Relationships
requires clearly specifying
permitted interactions between users
known as subjects, and resources known as objects.
This ensures that only authorized entities
can access specific resources
based on their established permissions.
Next, Continuous Authorization is used
to continuously evaluate access permissions
throughout a user session.
It adapts to changes in context
or security posture to dynamically enforce policies.
Finally, Context-Based Reauthentication requires users
to re-authenticate when certain monitored conditions change,
such as accessing sensitive data from a new location,
or shifting from a secure
to an insecure communication protocol.
For example, in a zero trust model,
an organization might define a relationship
by specifying that only finance team members
can access financial reports.
The organization can then continuously monitor
which members are accessing reports through the session,
and if a monitored member moves to a different network
or attempts to access particularly sensitive data,
reauthentication may be prompted.
This type of access management ensures
that access remains secure and contextually appropriate.
Then, we will explore Application Programming
Interface Integration and Validation.
Application Programming Interface
Integration and Validation ensures
that all interactions between applications and services
through application programming interfaces
are authorized, authenticated, and continuously monitored.
For example, application programming interface integration
can connect different applications and services,
enabling them to communicate and share data securely.
Application Programming Interface Validation may then verify
Application Programming Interface Interactions,
comply with security policies
by checking credentials, permissions,
and data integrity before allowing any data exchange.
Finally, we will look at Asset Control.
Asset control is maintaining a detailed inventory
and continuously validating the security status
of all assets within the network
to ensure they comply with security policies
and are protected against threats.
Asset control concepts include asset identification,
asset management, and attestation.
Let's explore each of these concepts in more detail.
Asset identification requires cataloging all devices,
applications, and data within the network
to create a comprehensive inventory.
Next, asset management is implemented
as the ongoing process of monitoring
and maintaining identified assets
to ensure they're updated, configured correctly,
and compliant with security policies.
Finally, asset attestation
verifies the security posture and compliance of assets,
often through periodic assessments or real-time checks.
To finish things off, we'll take a short quiz
to see what you learned during this section of the course,
and we will review each of those quiz questions fully
to ensure you can explain
why the right answers were right
and the wrong answers were wrong.
So, let's get ready to dive into Zero Trust Design
in this section of the course!