Authentication against custom Table In Silverlight4 Using RIA Service

In my previous article we had discussed about Data Binding ,Validation,Exception Handling ,Handling Multiple table and many more.But the first step in a business application deals with Authentication.Surely nobody wants data to be meshed up by an anonymous user so in this article we are going to implement Authentication to SOI (States of India) application.This post is restricted to FormsAuthentication model only.Also i am going to skip Authorization and due for next article.