How do authentication and authorization work together?

Every user sign-in request must be both authenticated and authorized. Doing one alone does not provide sufficient protection against unauthorized access. No user should be able to access system resources until they have been validated as the legitimate owner of the account and assigned permissions commensurate with their role in the organization.

What is an example of authentication and authorization?

A common example is logging in to a company application. Entering your username and password (and approving an MFA prompt) is authentication, because it proves you are the account owner. The application then checks your role to decide which features and data you can use, which is authorization. A standard employee might see only their own records, while a manager might see records for their entire team.

Why is authorization important for compliance?

Many regulatory frameworks require organizations to control who can access sensitive data and to keep records of those access decisions. Strong authorization, often through role-based or attribute-based access control, helps organizations meet these requirements. It also reduces the risk of insider threats by limiting access to only what each user needs.

How do I protect my organization against unauthorized access?

First, understand the difference between authorization and authentication. Then deploy an authentication solution with strong password requirements and MFA, along with an authorization solution that restricts access rights based on rules or roles in the organization. Together, these help protect against unauthorized actors gaining access to your systems.

Authentication vs authorization explained

Q: What is the difference between authentication and authorization?

Authentication validates that the user is the same person who registered for the account. Authorization defines what that user is able to do and what resources they can access after signing on. Both processes are required to secure system resources.

Authentication verifies who a user is. Authorization determines what that user can do. This article explains how the two work together to protect your organization from unauthorized access.

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Authentication vs authorization explained

Key takeaways

Authentication verifies who a user is. Authorization determines what that user can do.
Both processes are required to secure system resources. Doing one without the other leaves gaps.
Authentication always happens first. Authorization applies rules after identity is verified.
Multi-factor authentication (MFA) strengthens the authentication step by requiring two or more verification methods.
Role-based and attribute-based access controls strengthen the authorization step by enforcing least-privilege access.

The difference between authentication and authorization in web security

Authentication and authorization are two distinct security processes that protect organizations from unauthorized access. Authentication verifies that a user is who they claim to be. Authorization determines what that authenticated user is allowed to do.

Authentication	Authorization
Confirms user identity for system login	Determines access permissions to system resources
Prevents unauthorized access to the system	Prevents access to restricted resources
Always applied first	Occurs after authentication
Determines who the user is	Determines what the user can do
Credentials based	Role or policy based
Visible to the user	Often invisible or behind the scenes

Here is a simple example. You buy a ticket to a football game. At the gate, you show your ticket to the gate attendant. The attendant verifies that you have a valid ticket and lets you inside. The attendant has authenticated you. Now you try to go onto the field and mingle with the players. A security guard stops you and sees that your ticket only allows you to be in the seating area, not on the field. The security guard has checked your authorization and disallowed your access.

It is the same in cybersecurity. Authentication verifies that you are who you say you are and can log in to the system. Authorization determines what applications and data you are allowed to access. Knowing what authentication and authorization are, and understanding the differences between them, is essential to designing strong identity security.

Authentication: proving identity

Proving that the user is who they say they are is the logical first step in a secure login process.

Common types of authentication

The most common methods for proving identity fall into three general categories: something the user knows, something the user has, and something the user is.

Knowledge—something the user know

This is the most common, and also the most vulnerable, method of authentication. It includes passwords, PINs, and answers to security questions.

Possession—something the user has

This method includes devices the user has in their possession, such as authentication tokens, hardware keys, and one-time passcodes sent to a mobile device. New developments can use a trusted mobile device itself for friction-free authentication.

Biological—something the user is

This method uses biometrics to authenticate, including fingerprints, palm prints, facial recognition, voice patterns, and iris scans.

Advances in authentication: multi-factor authentication (MFA) and beyond

The use of passwords is still common in cybersecurity. To provide additional security, passwords are most often paired with additional authentication methods, such as a one-time passcode (OTP) or a biometric. The use of two authentication methods is two-factor authentication (2FA). The more general term, multi-factor authentication (MFA), refers to the use of two or more authentication methods. Using MFA helps guard against phishing attacks.

Recent advances in authentication methods include passwordless authentication, which eliminates the need for passwords completely and relies instead on biometrics or hardware keys based on standards like Fast Identity Online 2 (FIDO2). Risk-based authentication analyzes contextual signals such as device health, location, and login behavior to decide if access is authorized.

Authorization: verifying access rights

Once the user is authenticated, the next step is deciding what they are allowed to do. While authentication can be thought of as a yes or no decision, authorization applies rules to establish permissions and access levels. A weak authorization process can result in user accounts having access to secure or privileged areas, giving attackers a path to move laterally within the system. Strong authorization limits lateral movement, even if an account is compromised. In an insider attack, weak authorization can be especially dangerous. If your organization has compliance requirements, regulations typically require a strong authorization process.

Common authorization methods

Common authorization methods include role-based access control (RBAC), attribute-based access control (ABAC), policy-based access control (PBAC), and rule-based access control (RuBAC).

Method	What it does	Best used for
Role-based access control (RBAC)	Grants access based on the user's role in the organization	General access control across teams and departments
Attribute-based access control (ABAC)	Grants access based on user, resource, and environmental attributes	Fine-grained, context-aware access decisions
Policy-based access control (PBAC)	Grants access based on organization-wide policies	Complex environments with many overlapping rules
Rule-based access control (RuBAC)	Grants access based on predefined rules, such as time of day or location	Specific scenarios with fixed conditions

Identity and access management (IAM)

Together, authentication and authorization form the two core components of Identity and Access Management (IAM) solutions. IAM ensures that the right users and devices have the right level of access to the right resources at the right time.

Authentication and authorization best practices

So how do you implement effective authentication and authorization? The first step is to analyze your organization to determine roles and responsibilities. Decide who should be allowed what access so that employees can do their jobs but are not allowed in areas they do not need. Then pay attention to these guidelines.

Best practices for strong authentication

Implement MFA across all critical systems
Enforce strong password policies and do not allow default credentials
Implement passwordless authentication wherever possible
Continuously monitor login behavior for suspicious activity

Best practices for strong authorization

Start with least-privileged access rights as a base for assigning rights
Implement Zero Trust policies across the organization
Use RBAC for general access control
Use ABAC or PBAC for fine-grained, context-aware access control
Automate policy monitoring and enforcement, and regularly review rights assignments

Authentication and authorization for your organization

Authentication and authorization are two core components of any cybersecurity solution. You need to know that only valid users are accessing your system and that they are only accessing the data and applications they need to perform their job. To help you implement the right identity access solution for your organization, we have created an MFA evaluation guide. In it, you will get guidance on how to select an MFA solution, and you will see how Duo, with applications such as Duo Mobile that generates security codes and receives push notifications to facilitate MFA, can be the MFA solution you need.