Authentication and Authorization Tutorials

Dive into the core concepts and practical implementations of identity management within Microsoft platforms. This section provides a curated list of tutorials covering everything from basic authentication flows to advanced authorization strategies.

Getting Started with Azure AD Authentication

Learn how to integrate Azure Active Directory (now Microsoft Entra ID) for secure user authentication in your web applications. Covers token-based authentication and OAuth 2.0 flows.

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Implementing Role-Based Access Control (RBAC)

Understand how to define and enforce permissions using Role-Based Access Control. This tutorial guides you through creating roles, assigning permissions, and checking user access.

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Securing APIs with OAuth 2.0 and OpenID Connect

Explore best practices for securing your APIs using industry-standard protocols. This tutorial demonstrates how to issue, validate, and manage tokens.

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Two-Factor Authentication (2FA) Setup

Enhance your application's security by implementing Two-Factor Authentication. This guide walks you through common 2FA methods and their integration.

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Managing User Identities with ASP.NET Core Identity

Master the built-in ASP.NET Core Identity system for managing users, passwords, claims, and roles directly within your .NET applications.

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Advanced Authorization Policies

Go beyond simple role checks. Learn to create sophisticated authorization policies based on resource properties, user claims, and custom logic.

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Key Concepts

Understanding the difference between authentication (who you are) and authorization (what you can do) is fundamental. Here are some core concepts you'll encounter:

Authentication: The process of verifying the identity of a user or system. Common methods include passwords, multi-factor authentication, and biometric verification.
Authorization: The process of granting or denying access to resources based on the verified identity. This is often managed through roles, permissions, or policies.
Tokens: Digital credentials (like JWTs) used to represent a user's authenticated state and to carry authorization information.
Claims: Statements about a subject (user or entity) made by an authority. For example, "user is an administrator" or "user's department is IT".
Scopes: Permissions that define the extent to which a client application can access a resource.

Familiarize yourself with these terms to better understand the tutorials and implement robust security measures in your applications.

Example Snippet: Verifying a JWT Token

Here's a conceptual example of how you might verify a JSON Web Token (JWT) in a backend service. (Note: Actual implementation details vary by language and framework.)


// Example in C# using a hypothetical JWT validation library
var tokenHandler = new JwtSecurityTokenHandler();
var validationParameters = new TokenValidationParameters
{
    ValidateIssuer = true,
    ValidateAudience = true,
    ValidateLifetime = true,
    ValidateIssuerSigningKey = true,
    ValidIssuer = "your_issuer",
    ValidAudience = "your_audience",
    IssuerSigningKey = new SymmetricSecurityKey(Encoding.UTF8.GetBytes("your_super_secret_key"))
};

try
{
    SecurityToken validatedToken;
    ClaimsPrincipal principal = tokenHandler.ValidateToken(token, validationParameters, out validatedToken);
    // Token is valid. You can now access claims from 'principal.Identity'
    var userId = principal.FindFirst(ClaimTypes.NameIdentifier)?.Value;
    Console.WriteLine($"Authenticated user: {userId}");
}
catch (SecurityTokenException ex)
{
    // Token is invalid or expired
    Console.WriteLine($"Token validation failed: {ex.Message}");
}