Regardless of the vendor, when we discuss call routing in a telephony platform we’re almost always focused on the destination of the call. Similar to how the postal service operates, when the system is delivering the call or message, we are rarely focused on who the originator is. Keeping that in mind, it doesn’t take much imagination to come up with a few scenarios where it may be beneficial to block specific numbers, or ranges of numbers from reaching your end users.
In this blog post, I’ll show you how to implement a check on the calling party number (CPN) in a Cisco voice solution and keep those pesky spam calls at bay.
In order to illustrate the logic, let’s define some key components and run through a few examples.