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.

FORBES: Implications for CIOs and CTOs

Apigee Insights is a recognition in essence, that a fourth tier must be introduced into applications in addition to UI, Server, and Database.

FORBES: Implications for CIOs and CTOs

During the demonstration of RAD for the Server, Dave Mendlen, Visual Studio product planner, built what he called a "middle-tier business object" for a wine-selling Web site using six lines of code, an operation that he said would take "hundreds of lines of code" with the current version of Visual Basic 6.

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The availability of flash in server boxes is a disruption since, for the first time, fast and persistent storage is in the same tier as applications, Sinha says.

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