If your deployment includes multiple instances of Filtering Service that might handle a request from the same user, an optional component, Websense State Server, can be installed to enable proper application of time-based actions (Quota, Confirm) or overrides (Password Override, Account Override).
State Server is typically installed on a Policy Server machine, and only one State Server instance is required per logical deployment. A logical deployment is any group of Policy Server and Filtering Service instances that might handle requests from the same set of users.