good bye username and password

Whenever you use user names and passwords in your applications, consider using System.Net.NetworkCredential to pass the information around functions, it encapsulates those fields, and allows you to extend in the future to maybe use a domain as well.

In my case we're using it in a plugin architecture to authenticate against any system, using this class encapsulates those fields and allows the plugin to authenticate against most standard systems as it is not tied specifically to username and password