In today’s distributed and security-conscious IT environments, managing who has access to network devices and what they can do once they’re in is just as important as securing the network perimeter itself. That’s where TACACS+ comes in: a protocol purpose-built for centralized authentication, authorization, and accounting (AAA) of administrative access to network infrastructure.

While TACACS+ isn’t new, its role has become increasingly vital in the age of zero-trust architecture and compliance-heavy industries. And when implemented through a solution like FortiAuthenticator, its capabilities go far beyond the basics.

What is TACACS+?

TACACS+ (Terminal Access Controller Access-Control System Plus) is a protocol developed to authenticate users accessing network devices like switches, routers, firewalls, and access points. Its favored by network administrators for its granular access control, fully encrypted communications, and ability to separate AAA functions, unlike RADIUS, which combines them.

This separation allows for fine-tuned control over command-level access, giving organizations the ability to define precisely what actions a user can perform once authenticated.

Key Benefits of TACACS+

1. Stronger Security

TACACS+ encrypts the entire payload of communication between the client device and the authentication server not just the password. This provides more secure interactions, especially over untrusted networks.

2. Command-Level Authorization

Beyond just granting access, TACACS+ enables you to restrict which commands a user can run. This is crucial for environments where multiple levels of admin access are required.

3. Centralized Logging and Accountability

All login attempts and command executions can be logged centrally, providing visibility and audit trails necessary for compliance and forensic analysis.

4. Integration with Identity Systems

TACACS+ works seamlessly with external identity providers like Active Directory and LDAP, making it easier to enforce role-based access policies across your organization.

Use Cases: Where TACACS+ Shines:

1. Multi-Administrator Environments

In organizations with several network engineers or IT admins, TACACS+ helps ensure that access is traceable, permissioned, and accountable. No more shared passwords or uncontrolled privilege creep.

2. Regulated Industries

In sectors like finance, healthcare, and government, compliance requires strict logging and control over who can access what. TACACS+ is ideal for satisfying these requirements.

3. Service Providers and Large Enterprises

With hundreds of network devices and rotating teams, service providers benefit from centralized access control and dynamic policy enforcement that TACACS+ provides.

Why Choose FortiAuthenticator for TACACS+?

FortiAuthenticator isnt just another TACACS+ server, it’s a purpose-built identity and access management solution that integrates tightly with the Fortinet Security Fabric and supports standards-based protocols out of the box.

Heres what makes FortiAuthenticator stand out:

Tight Integration with Fortinet Devices

As part of the Fortinet ecosystem, FortiAuthenticator allows seamless integration with FortiGate, FortiSwitch, and other Fortinet products. This reduces deployment complexity and ensures consistent policy enforcement.

Flexible Identity Sources

Whether your users are in Active Directory, LDAP, or locally defined, FortiAuthenticator can authenticate them using TACACS+. It even supports multifactor authentication (MFA) for added security.

Built-in Logging and Analytics

All TACACS+ interactions are logged and searchable directly within FortiAuthenticator. This makes it easy to track who accessed what, when, and what they did without the need for third-party log collectors.

Scalable and Customizable

From small IT departments to global enterprises, FortiAuthenticator scales to meet your needs. You can define custom access policies per device, per group, or even per command.

Conclusion

TACACS+ is no longer a “nice to have”its a must-have for any organization managing sensitive network infrastructure. With command-level control, centralized logging, and secure authentication, it lays the foundation for strong administrative access management.

By leveraging TACACS+ through FortiAuthenticator, you get more than just protocol support. You gain a powerful, integrated identity solution built with Fortinet’s security-first approach. For organizations already using FortiGate or planning to consolidate identity across their environment, FortiAuthenticator is the natural and smart choice.