Client locates URN service. The URN might contain a hint about which URN service to contact. Client sends URN to URN service. Pass URN to a database service, e.g., handle server. May iterate to follow multiple indirections, and to obtain multiple records.
Service formats the reply for the client.
The data needs to be reformatted, either to translate from DB record format to client format, or because multiple formats have been obtained, or because a single composite reply must be constructed from multiple hits. An error has occrred. This definitely mitigates against much iteration and translation, and in favor of effective caching. Client interprets the reply. This directory contains several compressed tar files.