Windows Authentication with Web Services

Introduction

In the previous article in this series we saw how to use SOAP headers to authenticate a web service. In this article I will show you how you can use windows credentials to authenticate the consumer of your web service. Windows authentication is commonly used in intranet scenarios such as corporate portals.

How it works?

You can enable windows authentication for your web applications using web.config file. You need to set authentication mode to Windows in the <authentication> section. Additionally you need to set <authorization> section to deny anonymous access. Once you set these parameters in the web.config file the windows credentials of client machine (i.e. the machine which is accessing the web service) will be automatically passed to the web service. In side the web service you can then use Context.User.Identity.Name to get the user name of the user. In case client is not logged in to the domain, IE will pop up a dialog box to enter user id and password. Once user enters valid credentials he will be allowed to consume the web service.

Source Code

The sample source code provided contains two VS.NET projects. One is web service project that authenticates the user. The other is web application that consumes the web service.