Whilst browsing the Advanced Settings in the Enforce console under detection servers in 15.8 you notice settings related to REST and Cloud functionality such as RestDetection.UseSpiClient. These are not listed in the associated documentation page.
Release : 15.8
Component : Detection Server Settings
The settings below are actually only relevant for cloud detectors that integrate with our CloudSOC product and have no bearing on on-premise functionality. They can be ignored. Engineering is aware of their presence and they will likely be removed in a future version.