Authentication vs Authorization: Similarities and 5 Key Differences

What Is Authentication?

Often confused with authorization, authentication is essentially verifying the true identity of an entity. It enables access control by proving that a user’s credentials match those in an authorized user’s database. Identity verification can ensure system security, process security, and corporate information security.

Authentication helps ensure that only authorized users can gain access to protected resources on the network level. Limited access may include networks, ports, hosts, and other services.

In this article:

Types of Authentication

• Passwords—considered “old school” and less secure but are still commonly used in almost all authentication schemes. 
• One-time Password (OTP)‍—grants a user or device one-time access to a system. Authentication systems can deliver an OTP via email, text message, or a physical access token.
• Token authentication—grants access to a user or device based on an access token they possess. The token can be a hardware device or a software token passed to their browser from an identity provider.  Learn more in our detailed guide to Token-Based Authentication.
• Single Sign-on (SSO)‍—enables login to multiple applications via a central identity provider. The identity provider can be a service with a large user base, such as Google or Facebook, or an organizational identity provider, such as Active Directory. Learn more in our detailed guide to SSO Authentication.
• Biometric authentication—uses an inherence factor, such as the user’s face or fingerprint to identify them. There are increasingly sophisticated ways to compare a photo or scan of a person’s biological traits with a database of known identities.
• Multi-Factor Authentication (MFA)‍ – This methodology combines multiple forms of authentication to improve security. Typically, an MFA scheme will augment passwords with token-based authentication, OTP, biometric authentication, or several of these.
• Passwordless authentication – This is basically a variation on MFA, which uses two authentication factors including fingerprints, magic links, or OTAs to authenticate users without a password. 

Related: RBAC vs ABAC

What is Authorization?

Authorization, not to be confused with authentication, occurs after a system has successfully verified the identity of an entity. The system will then allow access to resources such as information, files, databases, or specific operations and capabilities. After a system authenticates a user, authorization verifies access to the required resources. It is the process of determining whether an authenticated user can access a particular resource or perform a specific action. 

For example, after a file server authenticates a user, it can check which files or directories that can be read, written, or deleted. This is where authorization comes into play.

Types of Authorization

• Discretionary Access Control (DAC)‍ – DAC determines privileges depending on the specific user and their access groups. A DAC model allows every object in a system to be accessed by a particular group or identity. Those in charge of granting authorization can provide admin permission to other users.
• Mandatory Access Control (MAC) – MAC determines authorization of entities at the operating system level. MAC commonly governs permissions for threads and processes, defining which files and memory objects they can access. 
• Role-Based Access Control (RBAC) – RBAC is used to enforce access controls defined in the DAC or MAC model. RBAC builds on predefined roles and privileges, assigns users to roles, and configures a system so that only specific roles can access each object.
• Attribute-based Access Control (ABAC) – ABAC is used to enforce access controls in a policy-based manner. It uses attributes, which can be attached to a user, a resource, an object, or an entire environment. An entity is authorized if the authentication system finds that all the attributes defined in the policy are true.

Related: RBAC vs ABAC

The Similarities Between Authentication and Authorization

Both authentication and authorization are critical components of network security and access management. They work together to ensure that only the right individuals have access to the correct resources.

• Security and access control: Both processes aim to secure access to systems, networks, and data. Authentication verifies the user’s identity, and authorization ensures that the user has the appropriate permissions.
• Sequential processes: Authentication and authorization are sequential processes. Authentication must occur first to establish user identity, followed by authorization to grant or restrict access based on predefined permissions.
• User management: Both are fundamental to user management within an organization, ensuring that only authorized personnel can access sensitive information and perform specific actions.
• Implementation frameworks: They often utilize similar frameworks and protocols, such as OAuth and SAML, to manage user credentials and permissions securely.

Authentication vs Authorization: The Differences

Here’s a quick overview of the differences between authentication and authorization. While both are important user management components, there are some key differences that must be considered before implementing them in the right places.

Here’s a quick overview of the differences between authentication and authorization. While both are important user management components, there are some key differences that must be considered before implementing them in the right places.

1. Basic Function

• Authentication identifies if users or other entities are who they say they are
• Authorization determines if a user or entity is allowed to access a particular asset

2. How they Work

• Authentication requires credentials or other information from an entity that can prove their identity
• Authorization uses policies and rules to decide whether to grant access to an authenticated user

3. When They Occur

• Authentication happens when the user first connects to a system
• Authorization happens after successful authentication

4. How They Transfer Information

• Authentication collects information from the user or entity in the form of text (e.g., passwords), unstructured data (e.g., image of the user’s face), or an access token.
• Authorization requires a token proving that the entity is authenticated and additional information about the entity to apply access rules.

5. Standards and Methods

• Authentication is commonly performed using OpenID Connect (OIDC) or other protocols (SAML, OAuth, etc) and may involve methods like passwords, access tokens, and biometric verification.
• Authorization is typically performed using OAuth 2.0 and may involve methods like RBAC and ABAC.

Authentication vs Authorization: Factors & Permissions

Authentication is based on “factors”—things a user possesses or can present to prove their identity. Authorization is based on “permissions”—defining what an authenticated user can and cannot do in a computing system.

Factors Commonly Used in Authentication

• Knowledge factors—“something the user knows.” These factors include passwords, access codes, personal identification numbers (PIN). These factors are considered to be the least secure, because attackers can easily compromise them.
• Possession factors—“something the user has.” These factors include physical identity documents, keys, hardware access tokens, mobile phones, digital certificates, software tokens, or anything else a user or entity possesses that proves their identity.
• Inherence Factors—“something the user is.” These factors include face images, live video of a user, fingerprint scans, or any other biometric reading. Many consider inherence factors to be the most secure, but sophisticated attackers can compromise them by faking biometric readings.

Permissions Commonly Used in Authorization

• Role-based permissions—grants permissions based on a group of users with a shared business role. Role-based permissions specify which resources that group is allowed to access. This permissions model supports the least privilege access principle, which states that a system should grant each user the minimal resources they need to perform their business role.
• Device permissions—grants permissions based on the device that is accessing the resource. This permission model might grant different permissions for trusted devices such as a corporate laptop, or non-trusted devices such as a personal mobile device. Authorization systems should adjust device permissions based on an evaluation of each device’s security posture.
• Location permissions—grants permissions based on the user or entity’s location. Authorization systems use this type of permission to limit access to sensitive resources for users connecting from home or other entities connecting remotely.

Authentication and Authorization in the Cloud

As organizations increasingly migrate to cloud environments, the need for robust authentication and authorization mechanisms becomes critical. These processes ensure that only legitimate users can access sensitive data and resources.

The Need for Authentication in the Cloud

Authentication is essential in the cloud to verify user identities before granting access to resources. The distributed nature of cloud services means that users can access systems from various locations and devices, increasing the potential for unauthorized access. Effective authentication methods help mitigate these risks by ensuring that only authenticated users can access cloud-based resources.

The Need for Authorization in the Cloud

Once users are authenticated, authorization determines their access levels and permissions within the cloud environment. Cloud services often host sensitive data and critical applications, making it vital to restrict access to only those who need it. Authorization ensures that users can only interact with the data and resources pertinent to their roles, minimizing the risk of data breaches and misuse.

Why Authentication Matters in the Cloud

• Securing access: Authentication mechanisms such as Multi-Factor Authentication (MFA) and adaptive authentication provide multiple layers of security, making it more difficult for unauthorized users to gain access.
• Simplifying user management: Federated Identity Management (FIM) allows for Single Sign-On (SSO), enabling users to access multiple cloud services with one set of credentials, simplifying login processes and reducing password fatigue.
• Enhancing user experience: Passwordless authentication methods, such as biometric scans and hardware tokens, offer secure and user-friendly alternatives to traditional passwords, improving the overall user experience.

Why Authorization Matters in the Cloud

• Enforcing least privilege: Authorization techniques like RBAC and ABAC ensure users have access only to the resources necessary for their roles, adhering to the principle of least privilege.
• Dynamic access control: Policies can be dynamically adjusted based on real-time data, such as user behavior and device security, providing flexible and adaptive security measures.

Granular permissions: Detailed access controls allow for fine-tuned permissions, ensuring sensitive data is accessible only to those with explicit authorization, reducing the risk of data leakage.

Which Comes First, Authentication or Authorization?

Authentication and authorization work together to control access to protected resources. Since authentication validates identity, this process comes first. Once identity is verified, the authorization process determines the user’s privileges and grants access accordingly. A user cannot be authorized before being authenticated first. 

Authentication and authorization work seamlessly together, making them seem like the same mechanism. However, the two components work as part of an organization’s access management program, an extensive process of controlling, tracking, monitoring, and managing users and system resources.

Authentication and Authorization with Frontegg

The industry standard today is to use Authentication providers to “build the door”, but what about Authorization (the door knob)? Most authentication vendors don’t go that extra mile, forcing SaaS vendors to invest in expensive in-house development. This often delays investment in core technology development, which negatively impacts innovation and time-to-market (TTM) metrics. 

Frontegg’s end-to-end user management platform allows you to authenticate and authorize users with just a few clicks. Integration takes just a few minutes, thanks to it’s plug-and-play nature. It’s also multi-tenant by design.

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