When I open the page I'm building, the user logged in by the network will log in to the page with that user, but without having to open a page for it, that is, my system will have to get the guy access the portal / system. I use:
VS2013 - MVC5 - Bootstrap - C # - SQL Server 2012
Set up your Web.config file with the following:
<system.web>
...
<authentication mode="Windows"/>
...
</system.web>
The user can be obtained using:
HttpContext.Current.User.Identity.Name
Or simply:
User.Identity.Name
See more here: link
If authentication goes with an Active Directory, VS Studio assists you, take a look at this tutorial to create a Single Sign On using Identity with Entity Framework.
Active Directory is a directory service implementation in the LDAP protocol that stores information about objects on a computer network and makes this information available to users and administrators of this network. (Source: Wikipedia)
Example Here: Windows Azure Active Directory
With this path of stones I developed a web app with authentication with the server where I work.