I have a .net web application that uses simple bind to query the LDAP. The application uses integrated windows authentication. Do you have any recommendations on which option to use to authenticate against the LDAP: 1. simple LDAP bind using the logged in user's credentials 2. simple LDAP bind using a service account created for the application's use 3. LDAP proxy user authentication - I dont have enough info about this, so i'd be grateful if someone could explain it's benefit, recommended use and sample .net code to do the query.