Server roles and extensions

New to ArcGIS Enterprise 10.5 was the concept of roles. Roles provide added functionality to ArcGIS Enterprise as deployed in your own infrastructure. Need to serve out and analyze imagery, rasters, or remotely sensed data? ArcGIS Image Server, formerly known as the Image Server Extension, allows you to serve massive imagery collections on the fly. At ArcGIS Enterprise 10.5.1, there are five licensing roles:

• GIS Server
• Image Server
• GeoEvent Server
• GeoAnalytics Server
• Business Analyst Server

Each server role requires its own instance of ArcGIS Server and a dedicated hardware resource; it is no longer recommended to deploy multiple roles to a single server for performance concerns. Many of these roles can also be deployed as distributed servers, allowing for the spreading out of processing across multiple servers.