VOIP spam opt-out filter? (Score 1)

A partial solution for VOIP service could be a spam like opt-in filter that blocks false area codes and prefixes - the phony first six digits. About half the calls I report have completely false numbers showing as CallerID. That seems pretty simple. And there are other standard ones like BizPromote and CardHolder Services that display and could be blocked. I recently installed Ooma and discontinued AT&T. Ooma premium has a community black list and the individual ability to black list, costs an extra $10 a month. I liked the free sample, will not consider expenses beyond basic until I've accumulated savings ($25/month) to recover the initial outlay.