Tag Archives: 2FA

Implement MFA using swiyu, the Swiss E-ID with Duende IdentityServer, ASP.NET Core Identity and .NET Aspire

November 10, 2025 · by · in .NET Core, ASP.NET Core, e-id, OAuth2, OpenId, Security, Self Sovereign Identity · 4 Comments

The post shows how to use the Swiss Digital identity and trust infrastructure, (swiyu) as an MFA method in an ASP.NET Core web application using ASP.NET Core Identity and Duende IdentityServer. The generic containers from swiyu are used to integrate the Swiss E-ID and the OpenID for Verifiable Presentations standards. Code: https://github.com/swiss-ssi-group/swiyu-idp-mfa-aspire-aspnetcore Blogs in this […]

Implement Phone verification, 2FA using ASP.NET Core Identity

March 3, 2025 · by · in .NET, .NET Core, ASP.NET Core · 2 Comments

This post shows how to implement phone (SMS) verification and two-factor authentication (2FA) using ASP.NET Core Identity. The solution integrates phone-based verification and 2FA mechanisms. The implementation uses ASP.NET Core Identity’s extensibility to incorporate SMS-based verification during user registration and login processes. SMS is no longer a recommended authentication method due to security risks but […]

Use FIDO2 passwordless authentication with Azure AD

January 17, 2022 · by · in Azure, Microsoft Entra ID · 3 Comments

This article shows how to implement FIDO2 passwordless authentication with Azure AD for users in an Azure tenant. FIDO2 provides one of the best user authentication methods and is a more secure authentication compared with other account authentication implementations such authenticator apps, SMS, email, password alone or SSI authentication. FIDO2 authentication protects against phishing. To […]

The authentication pyramid

March 17, 2021 · by · in Security · 7 Comments

This article looks at the authentication pyramid for signing into different applications. I only compare flows which have user interaction and only compare the 2FA, MFA differences. A lot of incorrect and aggressive marketing from large companies are blurring out the differences so that they can sell their products and so on. When you as […]

Send MFA signin requirement to OpenID Connect server using ASP.NET Core Identity and IdentityServer4

December 18, 2019 · by · in .NET Core, ASP.NET Core, dotnet, MVC, OAuth2, Security, Web · 3 Comments

This post adds the custom ASP.NET Core Identity, IdentityServer4 logic to check for the “acr_values” and react if a client application requests MFA for authentication. The “acr_values” parameter is used to pass the mfa value from the client to the server in the authentication request. Code: https://github.com/damienbod/AspNetCoreHybridFlowWithApi Blogs in this series Force ASP.NET Core OpenID […]

ASP.NET Core Identity with FIDO2 WebAuthn MFA

August 6, 2019 · by · in .NET Core, ASP.NET Core, javascript, MVC, Security, Web · 3 Comments

This article shows how FIDO2 WebAuthn could be used as 2FA and integrated into an ASP.NET Core Identity application. The FIDO2 WebAuthn is implemented using the fido2-net-lib Nuget package, and demo code created by Anders Åberg. The application is implemented using ASP.NET Core 3.0 with Identity. For information about Fido2 and WebAuthn, please refer to […]

Implementing Two-factor authentication with IdentityServer4 and Twilio

July 14, 2017 · by · in .NET Core, MVC, OAuth2, Security, Uncategorized, Web · 14 Comments

This article shows how to implement two factor authentication using Twilio and IdentityServer4 using Identity. On the Microsoft’s Two-factor authentication with SMS documentation, Twilio and ASPSMS are promoted, but any SMS provider can be used. Code: https://github.com/damienbod/AspNetCoreID4External 2017-09-23 Updated to ASP.NET Core 2.0 Setting up Twilio Create an account and login to https://www.twilio.com/ Now create […]