Create Secure Login Page Using ASP.NET

[sarah]

First and foremost, in ASP.NET it is important to use the built-in Forms Authentication rather than rolling your own authentication framework. This gives you plenty of flexibility in constructing your login routines and you can still rely on the sophisticated authorization features provided by the ASP.NET framework.
Also, if you are using ASP.NET 2.0, Forms Authentication has been greatly enhanced by providing a number of ready-made user controls for user logins, password recovery and new user creation. Pre-existing user databases and login routines have been created for Microsoft Access and Microsoft SQL Server, and other user data sources can be created by implementing your own Membership and Role Providers. Relying on these built-in framework capabilities reduces the amount of code that has to be written, decreases implementation time, and helps reduce the number of security flaws in your applications.

[vikramrandhawa]

In Asp.net 3.5 You Can use the Login Controls which are very secure and already built control in asp.net...We have to just drag the controls from the toolbox and write some code of it in web.config..