Network Infrastructure.
Network infrastructure is the backbone
of any modern organization.
It comprises the hardware, software, services,
and facilities required to support, manage,
and operate an enterprise network.
A critical aspect of network infrastructure
is the separation of network components,
which can be achieved either physically or logically.
In this lesson, we'll dive into these two methods.
First, Physical Separation.
Physical separation often referred to as Air Gapping,
is a security measure employed
to protect sensitive information.
An Air Gap system is isolated from other networks,
both local and internet.
By physically disconnecting it from those networks,
this isolation is achieved
by removing all direct or indirect connections,
including Wi-Fi, Bluetooth,
and other wireless connections.
An example of an Air Gap system
is a military or government network
holding classified information.
These networks are kept physically separate
from the public internet
to prevent unauthorized access and cyber-attacks.
Another example is an industrial control system
or ICS system
used in critical infrastructure,
like power plants or water treatment facilities.
These systems are often Air-Gapped
to prevent potential cyber, physical attacks
that could lead to real-world damage.
However, Air Gap systems are not infallible.
Sophisticated attacks such as Stuxnet
have demonstrated that Air Gap systems can be compromised.
Despite this, physical separation
remains one of the most secure methods
of protecting sensitive information,
provided that strict physical security measures
are in place.
Logical separation, on the other hand,
whilst creating boundaries within a network
that restrict access to certain areas
this is typically achieved through the use of firewalls,
virtual local area networks or VLANs,
and other network devices that can control traffic
based on rules and policies.
A common example of logical separation
is the use of VLANs in a corporate network.
VLANs can segregate network traffic
ensuring that data from one department,
such as human resources,
cannot be accessed by another department like marketing,
despite being on the same physical network.
This separation helps to improve security,
manage network traffic, and reduce congestion.
Another example is the use of firewalls
to create a screen subnet network,
there's a logical subnetwork
that contains the organization's external-facing services,
separating them from the internal network.
This prevents an attacker
who has gained access to the screen subnet
from easily moving to the internal network.
While logical separation
provides a high degree of flexibility
and is easier to implement than physical separation,
it is not as secure.
If not properly configured,
firewalls and other network devices can be exploited,
allowing unauthorized access
to restricted areas of the network.
So remember, both physical and logical separation
play crucial roles in network infrastructure and security.
Physical separation or Air Gapping
provides a high level of security
by completely isolating a system from other networks.
Logical separation,
while not as secure as physical separation,
offers more flexibility and is easier to implement.