ArcGIS Online content from ESRI is supported 24x7 with 99.9% availability. The system can support up to 1,000 concurrent users providing sub-second responses on the server and high speed user access.
The following diagram illustrates the system infrastructure for ArcGIS Online content from ESRI.
Users of ArcGIS applications or web applications connect to ArcGIS Online maps and task services from ESRI via the Internet. Users accessing the ArcGIS Online maps from ESRI connect through a distributed network of Akamai servers that support web acceleration and localized caching of content to improve performance.
The Data Center used to support ArcGIS Online content from ESRI provides a high bandwidth network to the servers to support high performance and capacity. The system includes multiple instances of Web and ArcGIS Servers, with multiple network attached storage (NAS) devices for the map servers to support high availability and capacity.