
## Why Use SAML SSO in Decoupled .NET Applications? {#Why Use SAML SSO in Decoupled .NET Applications?}

**Centralized Authentication**

Eliminate multiple logins—authenticate once and access all connected apps securely without additional credentials.

**Cross-Platform Compatibility**

Seamless integration with ASP.NET, ASP.NET Core, and microservices-based .NET applications.

**Tailored for Decoupled Apps**

Use our plugins to integrate SAML SSO into your decoupled .NET apps effortlessly.

**Compliance & Security**

Built on SAML 2.0 standards, ensuring encrypted communication and enterprise-grade security.

## How SAML SSO Works for Decoupled .NET Applications (Frontend + Backend) {#How SAML SSO Works for Decoupled .NET Applications}

A decoupled .NET application consists of independent apps (API, front-end, back-end) that need a unified authentication mechanism. Here’s how miniOrange makes it work:


 ![Working of Decoupled .NET Architecture](/blog/assets/2025/asp-net-decoupled-architecture.webp)

 **1. User Starts Login**

 When **User A** visits your frontend app, the app checks if the user is already logged in. If not, it starts the SSO process.

 **2. Frontend Redirects to Backend**

 The frontend passes the login request to the .NET backend to handle authentication.

 **3. Backend Sends SAML Request to Identity Provider (IdP)**

 The backend sends a SAML request to the Identity Provider (IdP) (like Azure AD, Okta, etc.) to ask for user authentication.

 **4. IdP Authenticates the User**

 The IdP checks the user's credentials. If everything is valid, it sends back a SAML response confirming the user's identity.

 **5. Backend Logs the User In**

 The backend reads the SAML response, logs in the user, and sets a claims cookie. Then it redirects the user back to the frontend.

 **6. Frontend Asks for a Token**

 After being redirected, the frontend sends a request to the backend to get a JWT token (a secure login token).

 **7. Backend Sends the JWT Token**

 The backend checks the request and sends a signed JWT token back to the frontend. The frontend now uses this token to make secure API calls.

 ## Use Case: SAML SSO for Angular, Vue.js & React Frontends with .NET Backend

 **Scenario:**

 Organizations are increasingly adopting decoupled apps, using modern frontends like Angular, Vue.js, or React that communicate with a centralized ASP.NET (.NET Core/Web API) backend. While this setup offers flexibility and scalability, it presents a challenge when implementing SAML Single Sign-On (SSO).

 **Challenge:**

 **SAML Incompatibility with Modern Frontends:**

 SAML depends on browser-based redirects, which don’t play well with frontend   frameworks like React, Angular, or Vue. 

 **Disjointed Authentication Experience:**

 The absence of a centralized login system leads to inconsistent user experiences and adds complexity and time to the development process.

**Unauthorized API Access:**

Unable to allow only authenticated users to access your .NET APIs. Implementing JWT could help prevent unauthorized data exposure.

**Lack of Role-Based Access:**

User roles (e.g., admin, viewer) needed to be enforced at the backend, keeping them hidden from the frontend and reducing security risks.

**No Frontend Code Modifications:**

The organization prefers not to alter frontend code—whether due to the risk of introducing bugs or the complexity of deployment pipelines.

**Solution:**

**Backend-Handled SAML Authentication:**

By introducing a .NET-based SAML Identity Broker, all SAML requests and responses are handled at the backend.

**Multi-IdP Support:**

With support for multiple Identity Providers like Azure AD, Okta, ADFS, and Google Workspace, organizations can centralize authentication across different systems.

**Secure Token Exchange + API Access:**

After successful SAML authentication, the backend issues a JWT or session token. Frontend apps use this token to make secure API calls, ensuring only authenticated users can access your .NET APIs.

**Role & Attribute Mapping:**

The backend fetches user roles and attributes (like email, department, and permissions) from the IdP and applies RBAC policies. This keeps role enforcement off the frontend, improving security.

**Outcome:**

By implementing the miniOrange SAML SSO solution for decoupled frontend-backend apps, organizations benefit in the following key ways:

**Centralized & Secure Authentication:**

Centralized SAML authentication ensures secure login, better control, and prevents token mishandling on the client side.

**Better User Experience Across Frontends:** 

Users on Angular, Vue.js, or React apps experience smooth, SSO-based login flows without redirects breaking the UI or interrupting sessions.

**Efficient Token-Based API Communication:**

 Post-authentication, JWT tokens are issued by the backend, enabling frontend apps to securely call APIs. 

**Granular Access Control with RBAC:**  

Fine-grained authorization logic that can enforce access restrictions at both the API and feature levels—without exposing role logic in the frontend.

**Support for Multiple Identity Providers:** 

miniOrange SAML SSO integrates with any SAML-compliant IdP—allowing organizations to manage multiple login sources from a single backend integration point.

## Why Choose miniOrange for SAML SSO in Decoupled .NET Apps? {#Why Choose miniOrange for SAML SSO in Decoupled .NET Apps?}

**Seamless Integration with .NET Backend**

Works with ASP.NET Core, Web API, and microservices. Ensure smooth and secure communication between .NET apps.

**Secure Token-Based Authentication**

Ensures safe API access using industry-standard JWTs. Prevent unauthorized access and maintain data integrity.

**Supports Multiple IdPs**

Authenticate your users using a variety of Identity Providers (IdPs) such as Okta, Azure AD, ADFS, Google Workspace, and more.

**Flexible Role & Attribute Mapping**

Go beyond basic authentication with custom role and attribute mapping. 

&nbsp;

## Resources {#more resources}
- [What is Single Sign-On (SSO)?](https://www.miniorange.com/products/single-sign-on-sso)
- [What is ASP.NET SAML Single Sign-On (SSO)?](https://plugins.miniorange.com/asp-net-saml-single-sign-on-sso)
- [Steps to Configure the ASP.NET SAML 2.0 Module](https://plugins.miniorange.com/asp-dot-net-saml-2-0-single-sign-sso-connector)
- [Setup Steps for ASP.NET SAML SSO Module](https://plugins.miniorange.com/asp-net-saml-sso-setup-guides)


Simplify Authentication Across Your .NET Applications.Eliminate repeated logins with SAML Single Sign-On (SSO) built for decoupled .NET apps. Let users log in once and securely access all your applications—streamlining access while ensuring enterprise-grade security and a seamless user experience.

Angular React Vue SSO with .NET

Secure Your Decoupled .NET Apps with SAML SSO