Show me how with code

In the Token based approach, the client application first sends a request to Authentication server with a valid credentials. Authentication server send an Access token to the client as a response. This token contains enough data to identify a particular user and it has expiry time. The client application then uses the token to access the restricted resources in next requests till the token is valid. If the Access token is expired, then client application can request for new access token by using Refresh token.

Tutorial for Building Simple Membership System using ASP.NET Identity 2.1, ASP.NET Web API, and AngularJS

https://github.com/tjoudeh/AspNetIdentity.WebApi

ASP.NET MVC, Web API, Web Pages, and Razor

https://github.com/aspnet/AspNetWebStack

This repo includes:

ASP.NET MVC 5.x
ASP.NET Web API 2.x
ASP.NET Web Pages 3.x
ASP.NET Razor 3.x

Secure a Web API with Individual Accounts and Local Login in ASP.NET Web API 2.2

https://docs.microsoft.com/en-us/aspnet/web-api/overview/security/individual-accounts-in-web-api

Web API with JWT

http://bitoftech.net/2015/02/16/implement-oauth-json-web-tokens-authentication-in-asp-net-web-api-and-identity-2/

Tutorial for Building Simple Membership System using ASP.NET Identity 2.1, ASP.NET Web API, and AngularJS

https://github.com/tjoudeh/AspNetIdentity.WebApi

Request JWT Token

Change Password Web API

http://bitoftech.net/2014/08/11/asp-net-web-api-2-external-logins-social-logins-facebook-google-angularjs-app/

Roles-Based Authorization Authentication ASP.NET Web API

http://bitoftech.net/2015/03/11/asp-net-identity-2-1-roles-based-authorization-authentication-asp-net-web-api/

Claims Authorization

http://bitoftech.net/2015/03/31/asp-net-web-api-claims-authorization-with-asp-net-identity-2-1/

Authentication OAuth

https://docs.microsoft.com/en-us/bingads/guides/authentication-oauth

Tutorial shows Authentication in AngularJS with ASP.NET Web API 2 and Owin Middle-ware using access tokens and refresh tokens approach

https://github.com/tjoudeh/AngularJSAuthentication

JWT in ASP.NET Web API

Tutorial shows how to Issue JSON Web Token in ASP.NET Web API 2 and Owin middleware, then build list of Resource Servers relies on the Token Issuer Party (Authorization Server)

https://github.com/tjoudeh/JWTAspNetWebApi/

Access Token

https://docs.microsoft.com/en-us/machine-learning-server/operationalize/how-to-manage-access-tokens

Use the access token to call Microsoft Graph

https://docs.microsoft.com/en-us/graph/auth-v2-user

Refresh Token - Read more

https://metamind.readme.io/docs/release-notes-einstein-platform-services

https://github.com/tjoudeh/AngularJSAuthentication

https://docs.microsoft.com/en-us/linkedin/shared/authentication/programmatic-refresh-tokens

OAuth for ASP.NET

https://github.com/matthewdunsdon/oauthforaspnet

https://bchavez.bitarmory.com/asp-net-identity-oauth-2-social-login-web-api-2-and-mvc-5-spas/#