Driver Scope implies the entries are scooped to the driver.
Driver Scope DirXML Variables are only available to the driver entry and the driver entry's subordinate entries; which includes all DirXML-Policies and DirXML-Rules running within the same driver.
When a DirXML-Driver
starts, the only Driver Scope Local Variables
that can exist are the Built-in IDM Variables
Other Driver Scope Local Variables maybe defined and once set, the values persists until changed or the driver is restarted.
Driver Scope Global Configuration Variables
are defined on the DirXML-Driver
There might be more information for this subject on one of the following: