SSRS - By pass specific user to Reporting Server

When we browse to Reporting Server, it usually ask a username and password to access. However, sometime we want to avoid that by using specific account (treat like webapp that know db password). To do that we have to implement a custom web application that host a web page which can load ReportViewer. Then that page have to specifically implement parameter specification before by pass its parameters to ReportViewer control. The steps are shown below:

By pass anonymous access for reports using custom web app as a proxy

1. Create ReportViewer in custom web app
2. Using the WebForms ReportViewer Control
3. Set credentials for ReportViewer
4. Set Report Parameters with Credential