What is the Difference Between Authentication and Authorization
In the world of information security, authentication and authorization are crucial concepts for protecting systems and data. Though often used together or interchangeably, they refer to distinct security processes with an important technical difference.
This article will explain what authentication and authorization are, how they work, and why properly implementing them is critical for any application or service that handles sensitive user information. We’ll also look at common implementations like OAuth and RBAC to help clarify how authentication and authorization operate in real-world scenarios.
Understanding the distinction between identification/authentication and access control/authorization is key for developers, IT pros, and security practitioners looking to build secure systems and applications. Let’s examine how these vital security controls allow users to prove “you are who you say you are” and “you are approved to do what you are trying to do.”
Key Takeaways
- Authentication confirms your identity by validating who you are, while authorization controls your access by determining what you can see and do.
- Authentication usually requires a username and password. Authorization may limit system access and feature rights based on user type or permissions level.
- OAuth is an authentication protocol that allows you to approve one application interacting with another without exposing your password.
- Multi-factor authentication (MFA) adds extra identity confirmation steps like biometrics, security keys, or one-time codes.
- Role-based access control (RBAC) restricts system access and features by user role or group membership.
- Authentication verifies you are who you say you are, while authorization verifies you have the right to do what you’re trying to do.
Head-to-Head Comparison Between Authentication vs Authorization
| Feature | Authentication | Authorization |
| Definition | Verifying identity | Granting access permissions |
| Purpose | Establish trust | Control access to resources |
| Timing | Occurs first | Follows after authentication |
| Credentials | Username, password, biometrics | Roles, permissions, privileges |
| Mechanism | Password, tokens, biometrics | Access control lists, policies |
| Scope | Global (system-wide) | Resource-specific |
| Principles | Identification, verification | Least privilege, need-to-know |
| Examples | Login, digital signatures | File permissions, database access |
| Vulnerabilities | Brute-force attacks, phishing | Privilege escalation, misconfigurations |
| Protocols | OAuth, SAML, Kerberos | RBAC, ABAC, ACL |
What is Authentication?
Authentication is the process of verifying the identity of a user or process. It involves validating a claim to a unique identifier, often by requiring the user to present some evidence that they are who they say they are.
Authentication confirms that users are who they claim to be before allowing access to a system or application. It establishes if a user is legitimate by associating them with a verified digital identity.
Some common examples of authentication factors include:
- Username/Password: This is the most common authentication method, requiring the user to enter a registered username and password.
- Security Questions: Common secondary verification, asking users to confirm secret questions or personal details.
- One-Time Codes: Sent via email, SMS texts, or an authenticator app to confirm user identity.
- Security Keys: Physical tokens that connect via USB or wirelessly to provide cryptographic authentication.
- Biometrics: Fingerprints, facial recognition, retina scans, or other measurements of unique biological traits.
- Phone Verification Involves Sending a code to a user’s phone to confirm that they have access to the device.
Multi-factor authentication (MFA) combines two or more factors for enhanced security – for example, a fingerprint scan in addition to a password. This makes it much harder for attackers to gain access to accounts fraudulently.
Ultimately, authentication aims to irrefutably establish that someone is who they claim to be before any system grants them access. By verifying user identities, it forms the first line of defense against unauthorized use.
How Does Authentication Work?
There are a few steps that comprise the authentication process:
- A user provides an identifier – typically a username or email – to initiate authentication.
- The user then provides an authentication factor, such as entering a password or scanning a fingerprint, as proof of their identity.
- The system validates the authentication factor against the user’s registered data to verify that it matches. For example, it compares the entered password to the one hashed and stored for that username.
- Following successful validation, the user’s identity is authenticated, allowing them to sign in and access the system.
- The system typically sets an authentication session with a defined lifespan, allowing the user to remain logged in until the session expires. After the session ends, the user must re-authenticate to establish a new session.
Developers have considerable flexibility in selecting and implementing authentication schemes. Some additional aspects of authentication include:
- Federated Authentication: Delegates authentication to a trusted external party, like using your Google account to log in to other websites.
- Single Sign-On (SSO): Allows a single authentication action to access multiple applications, avoiding repeated logins.
- Continuous Authentication: Frequently re-verifies user identity after initial login, like requiring frequent re-entry of a password or one-time code.
- Adaptive Authentication: Applies various authentication factors based on the context, like stepping up from a password to MFA for risky transactions.
Authentication aims to confidently establish user identities at the start of sessions, so the system knows exactly who is accessing it at all times.
What is Authorization?
Authorization is the process of determining what a user has permission to access and what actions they can perform after their identity has been authenticated. It establishes the precise access privileges for an authenticated user.
Some examples of common authorization methods include:
- Role-Based Access Control (RBAC) restricts system access and features based on a user’s role, such as “admin,” manager,” or “guest.”.”
- Access Control Lists (ACLs) define users’ and user groups’ access rights to specific objects like files, folders, and applications.
- Attribute-Based Access Control (ABAC) Grants access rights based on various user attributes, such as location, time, or department.
While authentication verifies that users are who they claim to be, authorization verifies that authenticated users have adequate permissions to do the actions they’re attempting. It allows system administrators to limit the features and information each user has access to based on their identity, role, and context.
Authorization ensures users can only access resources and perform actions according to defined policies. It prevents improper access that could lead to data exposures, breaches, or fraudulent activities.
How Does Authorization Work?
Authorization requires first successfully authenticating the user to establish their identity. After authentication, the authorization process proceeds as follows:
- The user tries to access a resource or perform an action, like viewing a folder or submitting an order.
- The authorization system checks what permissions the authenticated user has been granted.
- The authorization system evaluates applicable policies to determine if the user has rights for the attempted access or activity.
- If the user has sufficient permissions, they are authorized, and the action is allowed. Otherwise, authorization is denied, and the action is blocked.
- Authorized access details are often logged for auditing and monitoring purposes. Declined authorization attempts may also be logged, as this could indicate hacking attempts.
Authorization schemes grant different access rights to users depending on factors like their role, environment, time of access request, and other attributes. Some other authorization aspects include:
- User Provisioning: Creating, managing, and deleting user accounts and their attributes that impact access rights.
- Entitlement Management: Defining what access privileges user roles or groups have throughout their lifecycle.
- Governance: Establishing processes and overseers responsible for setting and enforcing authorization policies.
Well-designed authorization minimizes overexposure and limits users to only the data and actions they absolutely need for their role. This minimizes risks from both malicious misuse and accidental mistakes.
Why is the Difference Important?
Understanding the distinct goals and methods of authentication versus authorization is crucial for building secure applications and protecting access to sensitive systems or data.
Trying to use authentication alone for access control can open up security risks. Authentication confirms a valid user but doesn’t dictate what they can see and do within the system. Relying solely on authentication would mean granting all valid users full access to all resources, eliminating critical access restrictions.
On the other hand, authorization relies on effective authentication. Applying authorization without rigorous authentication allows for situations where you don’t truly know who is being granted access rights.
Using authentication together with layered authorization provides identity verification along with granular access controls. This ensures users can only access resources and perform actions necessary for their specific role and context, following the principle of least privilege.
The balance of authentication and layered authorization provides optimal security and compliance. Misunderstanding or misconfiguring their difference can leave applications, systems, and infrastructure exposed.
Examples of Authentication and Authorization
Usernames and Passwords
The most common example is a simple username and password. When you enter your username and password to log into an application, you are authenticated, as the system checks if your credentials match what’s on record for your user account.
However, entering the correct username and password only verifies your identity – it doesn’t automatically give you full access to all resources and actions. The system then checks your authorization settings to determine what you specifically are allowed to access and do based on your user account privileges.
For example, users belonging to an “admin” or “manager” role may have permission to create or delete user accounts. In contrast, regular users may only be authorized to view their account details. Proper authorization controls ensure users can only perform actions and access information appropriate for their role within the application.
Multi-Factor Authentication
Many applications now use multi-factor authentication (MFA) for enhanced security. After entering your password, you may also be prompted to enter a one-time code sent to your mobile phone or confirm your identity via a biometric fingerprint scan.
The additional authentication factors further validate that you are who you claim to be before logging you into the system. However, after successful authentication, you’ll still only be authorized to access resources and perform activities suitable for your user account. So, multi-factor authentication strengthens identity verification, while defined authorization policies control the access rights of each authenticated user.
OAuth
OAuth provides authorization for applications to access functionality and data on other platforms on a user’s behalf without needing their login credentials.
For example, when you log into an app using your Google account, you are authenticated via Google and cryptographically authorized to connect that app to your Google services like Gmail, Calendar, Drive, etc. However, the app will still only have permission to access and perform actions on specific Google resources based on the authorization scope you approved.
So, OAuth allows simplified authentication and authorization delegation to third-party apps while still restricting their access to only designated user data and actions. The user retains control over what integrations they authorize.
Role-Based Access Control (RBAC)
RBAC is a key authorization method that restricts system access and features based on a user’s role. For instance, an organization may define “employee,” “manager,” and “executive” roles with increasing levels of access.
Though all personnel may authenticate via the same login portal with usernames and passwords, their role designation will determine what applications, menus, data, and actions they are authorized to use or perform after successful login. This limits all personnel to only the access required for their duties, minimizing exposure.
Proper RBAC implementations combine reliable authentication with appropriate access restrictions by role. This enhances security while enabling the organization’s productivity.
Authentication and Authorization Best Practices
Some best practices for applying authentication and authorization include:
- Authenticate users before authorizing: Always verify identity before granting access and privileges.
- Use multi-factor authentication when possible: Adds extra identity confirmation for better security.
- Implement the principle of least privilege: Only authorize necessary access. Start strictly and open up as required.
- Enforce separation of duties: Sensitive tasks should require multiple users to complete.
- Rotate credentials periodically: Change passwords, refresh API keys, update service accounts, etc. regularly.
- Use salted password hashing: Adds complexity to stored hashes to make password cracking extremely difficult.
- Log events and monitor anomalies: Watch for failed login attempts, privilege escalations, etc.
- Establish user lifecycle management: Provision, modify, and de-provision user accounts and access systematically.
- Continually audit policies and permissions: Review authorization rules frequently for appropriateness.
- Provide role-based training: Educate personnel on policies relevant to their role’s access and duties.
- Stay up-to-date on emerging threats: Monitor security publications and vendor notices to close vulnerabilities promptly.
Adequately securing systems and sensitive business data requires applying rigorous authentications paired with granular authorization schemes. Failing to understand their distinct purposes and implement them properly leaves organizations open to breaches and regulatory non-compliance.
Conclusion
Authentication and authorization are two distinct but related security measures. Authentication verifies the identity of a user, system, or entity, ensuring that they are who they claim to be. Authorization, on the other hand, determines what actions or resources an authenticated entity can access or perform. Together, they provide a comprehensive security framework for protecting sensitive information and resources. Authentication establishes trust, while authorization enforces access control policies, ensuring that only authorized individuals or systems can perform specific actions or access specific resources. Implementing robust authentication and authorization mechanisms is crucial for maintaining data integrity, privacy, and overall system security.
Frequently Asked Questions About Authentication vs Authorization
What’s the main difference between authentication and authorization?
The main difference is that authentication verifies user identities while authorization controls access and actions based on permissions. Authentication confirms who you are, while authorization determines what you can do.
Why is authorization still needed after authentication?
Because authentication only establishes identity – it doesn’t define what resources and actions the user should have access to after logging in. Authorization provides those access controls.
Can OAuth be used for authentication and authorization?
Yes, OAuth allows simplified single sign-on authentication by connecting apps to a user’s existing login on another platform. It also provides delegated authorization to those apps to access designated resources and actions without exposing the user’s login credentials.
Why log failed login attempts?
Logging failed logins can help detect brute force hacking attempts so you can block repeated unauthorized access tries. This protects accounts from being compromised.
Should passwords expire periodically?
Regular password changes were once common but have yet to be universally recommended. Forcing frequent updates can frustrate users, leading to weaker credentials. However, some highly sensitive systems may still mandate periodic rotation.
Priya Mervana
Verified Web Security Experts
Priya Mervana is working at SSLInsights.com as a web security expert with over 10 years of experience writing about encryption, SSL certificates, and online privacy. She aims to make complex security topics easily understandable for everyday internet users.
