Our organization is currently facing the possibility of hosting a large-scale .NET web application with a SQL back-end. The application must be able to accommodate 2,000+ simultaneous users and the database itself will have around 1,000,000 records.

We have a number of questions, and would greatly appreciate any suggestions you may have, regarding:
1.) How much bandwidth will this require?
2.) What about backup solutions (on-site and off-site)? This data is incredibly sensitive.
3.) What kind of web servers and load balancing scenario would we need?
4.) How much space would we roughly need for data storage?

Thank you for your time.

Matthew