Instructor: In this lesson,
we will learn about fail-safe mechanisms.
Fail-safe mechanisms are systems designed
to default to a secure state or a safe operational mode
in the event of a failure or security breach.
Fail-safe mechanism concepts include
fail-secure and fail-safe.
Fail-secure mechanisms prioritize maintaining security
by locking down access or shutting down critical functions
when a failure occurs.
Fail-secure mechanisms prevent unauthorized access
even if it causes a temporary denial of service.
Let's learn more about fail-secure and fail-safe.
First, we have fail-secure.
Fail-secure mechanisms are critical
in systems where security must remain the highest priority,
even in the face of unexpected issues.
In a fail-secure system, when a failure occurs,
the system shuts down or locks access
to protect against unauthorized entry or data breaches.
The main goal of fail-secure
is to maintain a strict security posture,
even if that means temporarily disrupting availability.
For example, if a server
handling sensitive customer information
experiences a critical error,
a fail-secure approach would immediately cut off all access
to the server,
preventing anyone from reaching potentially vulnerable data
until the issue is resolved.
This measure ensures
that sensitive information stays protected,
but it may limit authorized users access temporarily.
On an enterprise scale,
a fail-secure mechanism could look like a database
that automatically locks down access
during unexpected incidents.
For example, suppose a bank's core database
containing confidential financial data
detects an anomaly, like an unusual data request pattern,
which could signal a breach attempt or internal error.
A failure secure setup would immediately block access
to the database,
safeguarding sensitive financial records
from possible compromise,
though it may also temporarily prevent legitimate users
from accessing the system.
In this case, with fail-safe,
the highest priority is keeping the data secure
and ensuring no unauthorized access occurs
during the vulnerability period,
even prioritizing that over customer convenience.
Second, we have fail-safe.
In contrast to fail-secure,
fail-safe mechanisms emphasize safety,
focusing on ensuring an IT system continues to function
in a manner that prevents harm or damage during a failure.
Think of the difference between fail-secure and fail-safe
like the response of two different doors in a power outage.
Imagine one is the main entry to a vault
representing fail-secure,
and the other is an emergency exit door
representing fail-safe.
The fail-secure door guarding valuable assets
will lock up tight when the power goes out.
This approach prioritizes security.
Even if someone can't get in temporarily,
the valuables remain protected.
In this approach, security is maintained above all else.
Conversely, the fail-safe door is a safe exit
in case of emergency.
So, in the power outage, this door unlocks,
ensuring people can get out quickly
if there's a fire or another risk.
Here, safety is the priority,
ensuring no one is harmed by being trapped inside,
even if it slightly reduces security
by allowing potential outside access.
In IT systems,
fail-secure mechanisms lock down the data or systems
to prevent unauthorized access when something goes wrong,
while fail-safe mechanisms
prioritize safe continuous operation,
even if that means sacrificing a bit of security
to ensure ongoing functionality.
In an enterprise environment,
network switches or routers
can be configured to detect a failure
in the primary external internet connection
and automatically reroute traffic
through an alternative link,
even if the secondary link has lower security controls
or bandwidth capacity.
For example, if a company's
primary internet connection fails,
a fail-safe configuration could redirect traffic
to a secondary internet service provider
or virtual private network
to maintain operational continuity.
While this backup path
may lack the same level of firewall protection
or traffic inspection as the primary route,
it ensures that employees retain internet access
and can continue working without interruption,
thereby prioritizing business continuity
over strict security
during the failover period.
So, remember, fail-safe mechanisms are designed
to keep systems secure or safe
during unexpected failures or security breaches.
There are two primary types, fail-secure and fail-safe.
Fail-secure mechanisms prioritize security
by locking down access or shutting down critical functions
when issues arise,
even if it temporarily disrupts availability.
In contrast, fail-safe mechanisms
focus on maintaining safe and continuous operations,
allowing systems to continue functioning during a failure,
even if some security measures are relaxed.
Together, these approaches help organizations
manage risks effectively,
balancing security and operational continuity
based on the specific needs of the situation.