Well this depends on delivery medium. If the outbound call is routed to a SIP URI instead of over TDM, you actually have no idea where that calls going. A DID

Well this depends on delivery medium. If the outbound call is routed to a SIP URI instead of over TDM, you actually have no idea where that calls going. A DID (direct inbound dial) is physically punched down into an exchange somewhere near the actual physical area (415 exchanges are physically punched down in or around San Francisco, for example). If calling a specific DID results in a forward to a carrier like, say, bandwidth.com, then the routing commands applied after that would not be traceable (or at least not easily). In short, only if you know the method of delivery, and I'd argue that it's virtually impossible to know what kind of routing a number you're calling will trigger. Does that help? Inbound caller ID is just Fubarr'd because you can fake it in two seconds.