3.1.1 Abstract Data Model
This section describes a conceptual model of possible data organization that an implementation maintains to participate in this protocol. The described organization is provided to facilitate the explanation of how the protocol behaves. This document does not mandate that implementations adhere to this model as long as their external behavior is consistent with that described in this document.
A data structure that tracks the available NSPI servers and their current state is beneficial to any implementation of this protocol. Tracking this internal state means the client is more likely to get a valid NSPI server name and connect successfully on the first try. The NSPI referral server is not required to connect to the NSPI server in order to service clients; therefore, it is important for an implementation of this protocol to use some method to maintain up-to-date information about available NSPI servers. This ensures that clients who call the RfrGetNewDSA method are not given the name of an NSPI server that is not functioning.