Anurag,
This approach blocks all calls coming from the PSTN, regardless of type. If you are referring to a SIP REFER, then it must have an attached ANI.
Patrick, It is tedious to go back and redo all of your call flows. However, if you add this at the top of each one when it is being modified, it isn't much work at all. We used this approach at a healthcare company and after two or three months, we had them completed. We then focused on the remaining call flows (apps over in Engage Cloud) and those were completed in 2 days by one member of the Dev team, if memory serves me right.
Stuart, agreed. We made a feature request to add this into every starting call block in Designer as Out of Box for Engage Cloud, along with an associated data table. It wasn't difficult at all to do this after the fact, but if it was put out there as a default, more companies would build it into every call flow/app from their start with Genesys. And 250 phone numbers is not nearly enough for most enterprise companies. Engage Cloud isn't limited by this restriction and we had much more than that.
When I left, we were in the process of allowing end users to block phone numbers via an API through ServiceNow. If they did it for nefarious reasons, their employee ID was logged. This helped us with repeat abuse callers in the nighttime as well as faxes misdirected to high volume TFNs. This happens many times every day in healthcare firms, so it's a big issue.
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