The fourth tier is an Edge Server that brings in contextual data, tracks and analyzes interactions through APIs, provides caching, and supports real time analytics to operationalize all available signals.
Doncaster's rating has been published inthe Audit Commission's Comprehensive Performance Assessments (CPA) - the annual data for all English single tier and county councils.
In addition, thedata delivery systems (in the internet cloud) that serve the thin client model would also benefit with a tier of fast flash memory for rapid playout of content to the thin clients.