IoT applications will come in all shapes and sizes but no matter the size, availability is paramount to support both customers and the business. The most basic high-availability architecture is the typical three-tier design. A pair of ADCs in the DMZ terminates the connection. They in turn intelligently distribute the client request to a pool (multiple) of IoT application servers which then query the database servers for the appropriate content. Each tier has redundant servers so in the event of a server outage, the others take the load and the system stays available.