If you have an ISDN origination, you can block your calling party number. This is a basic feature of ISDN. The Telco switch “can” set your number and will deliver this ANI if you do not provide a different number for display. Basically though, the Telco switch will not block or change what you send on ISDN. The Orig CPE has the upper hand. What it sends will override any telco settings (at least on our network, that’s the case). If you supplied 111-222-3333 as the Calling party number, it would be sent. This is different to the charge number which is set elsewhere.
Many collection agencies will either block their own Calling Party Number or select a different one. Doing the latter causes problems as sometimes they select a number that belongs to someone else. (Not good!).
Anyway, you can set the CPN as Private and it will usually not display on the term end. it will go across the network as “Presentation Not Allowed”.
This too can cause issues with call completion. Another feature of ISDN is the ability to block calls from unknown originations. Basically, the term end is saying that if you don’t provide me a valid ANI, I will not answer.
It’s not that common, but it is a capability.