External vs ONVIF alerts in Blue Iris from Dahua camera events

[digger11]

Can anyone explain which Dahua events are classified by BI as ONVIF events and which are classified as External events?
When I look at ONVIF events in BI, only one of my cameras has any events, All the rest of my Dahua camera IVS or motion events seem to show up as External events.
I have yet to spot what the difference is.

 

[wittaj]

From the help file:

Motion/Alarm trigger signals received from ONVIF GetEvents PullPointSubscription will be
classified as either having an ONVIF source or an EXTERNAL source depending on whether
these events are unary or binary and you select the Trigger until reset option. Events with
“begin” and “end” (binary) components will be classified as ONVIF triggers. Single events
(unary) will be classified as EXTERNAL triggers.

What I seemed to notice, and was probably just coincidental was sometime around the time that ONVIF "suspended" Dahua and Hikvision, the ONVIF triggers changed to External Triggers in BI.