What Is Kerberos and How Does It Work?

Cyberattacks are a significant threat to every organization in the world. No firm is safe in this data-driven era, as cyber attackers steal vital corporate information for their profit and destroy organizations. According to Forbes, cybercrime will cost approximately US$6.1 trillion by 2021. As a result, industries should consider strategies to prevent these cyberattacks. The majority of them currently do so through the usage of Kerberos. It is a network authentication technique that aids in the verification of identity to obtain legal authorization. This article will explain what Kerberos is and how does it work. 

What is Kerberos?

Kerberos provides a centralized authentication server that is responsible for authenticating users and servers. Kerberos Authentication uses a server and database to show clients. Kerberos is implemented as a dedicated third-party server dubbed the Key Distribution Center (KDC). Each network user and service is a principle.

In a nutshell, it assists an organization in keeping its privacy. Now that you understand what Kerberos is, you may be wondering why to choose Kerberos. There are other authorization protocols; however, this one is the most advanced of them all. Cybercriminals will find it increasingly difficult to compromise the Kerberos authentication system. There will always be vulnerabilities in an organization that it must address through Kerberos to protect it from cybercriminals. The program is supported by various standard operating systems, including Windows, UNIX, and Linux. 

Kerberos’ primary components are as follows:

• Authentication Server (AS): The Authentication Server performs initial authentication and ticket generation for the Ticket Granting Service.
• Database: The Authentication Server checks that users have appropriate access privileges to the database
• Ticket Granting Server (TGS): The Ticket Granting Server is responsible for issuing tickets on the Server’s behalf.

Why use Kerberos?

There are four primary reasons why it’s a reliable security solution:

• Kerberos is mature – Because of its widespread use and extensive research, Kerberos is an established technology. That’s vital in the field of security.
• Kerberos matches the modern distributed systems’ requirements: Because it was developed in response to a clearly defined and well-thought-out series of authentication requirements in an inclusive environment with insecure communication networks, Kerberos has turned out to closely match the authentication requirements of modern distributed systems operating over Internet Protocol-based networks. 
• Kerberos is structurally sound. Kerberos has explicit architectural and functional abstractions, which has allowed it to evolve and interface easily with other systems.
• In most major operating systems and many frequently used software applications, Kerberos is already integrated. It is a vital aspect of today’s IT infrastructure.

What are the applications of Kerberos?

Every business now utilizes Kerberos to keep its systems secure and free of cybercrime. Its authentication processes are built on a foundation of regular audits and many forms of authentication. With Kerberos, you’re achieving security and authentication at the same time.

You can find it in a wide range of applications, including email delivery systems, text messaging, NFS, signaling, and POSIX authentication. As well as SMTP, POP, HTTP, and many others, it’s found in many other networking protocols. It’s also used to secure client/server applications and several operating system components.

Key steps in Kerberos authentication:

Kerberos Authentication has the following steps:

• The PC client connects the domain by logging in. A Kerberos Key Distribution Center (KDC) receives a TGT request to provide a ticket.
• The Kerberos KDC provides the PC client with a TGT and a session key.
• The Kerberos KDC receives a ticket request for the application server. The PC Client, TGT, and authenticator are all part of this request.
• PC Client receives a ticket and a session key from the Kerberos KDC.
• The application server receives the ticket. The Server can verify the authenticity of the PC Client after receiving the ticket and authenticator.
• The PC Client receives a response from the Server with a new authenticator. The PC Client will be able to authenticate the Server once it gets this authenticator.
• Remedy Single Sign-On, the core authentication module used by many BMC systems, also supports Kerberos integration.

Benefits of Kerberos authentication

• Kerberos is an authentication service that has several advantages.
• Effective access control is made possible via the Kerberos authentication system. All logins are tracked in one place, and security standards are enforced consistently.
• When using Kerberos, service systems and users can verify each other’s identities without exchanging passwords. Users and servers can be confident that the counterparts they are communicating with during the entire procedure are genuine.
• Kerberos tickets have timestamps and lifetime data, and administrators can limit how long an authentication will last.
• Kerberos authentication is reusable and long-lasting. The system will only need to verify a user a single time. After that, the user will authenticate themselves without entering their personal information again for the ticket duration. 
• Kerberos is a security verification system because it uses multiple secret keys, third-party authorization, and cryptography. Because passwords and private keys are not exchanged over networks, attackers cannot impersonate users or services.

In what ways does Kerberos fail?

Kerberos is a powerful security threat management tool. There are few challenges to overcome. Few common flaws are

• With several secret keys, third-party authority, and cryptography, Kerberos is a reliable authentication protocol. Because passwords and secret keys are not exchanged over networks, attackers cannot impersonate users or services. 
• For a network service to use a different hostname, it will need its own set of Kerberos keys, which can cause issues with cluster and virtual hosting.
• The date and time settings on each host must be in sync with one another. Authentication will fail if you don’t do this because of the limited number of tickets available.

Last words

It’s a lot more challenging to implement Kerberos authentication practically. It is the industry standard for creating safe software applications because of its foundational authentication mechanism. For a long time, it’s been a tried-and-true security solution. The majority of operating systems use it to generate cryptographic algorithms. Kerberos’ importance won’t diminish unless we find a better method than Kerberos.