I found a way to block "Neighbor Spoofing Robocall" using OBi device + GV.
Hypothetically assuming:
1. my GV number is 402-346-1400 and this is my SP1;
2. I have 3 friends in the neigbor area, 402-346-1401, 402-346-1402 and 402-346-1403
I would like to block 402-346-xxxx except for 3 friends' numbers.
First I set up 2 user defined digitmaps:
wlist = ( (+1|1)? 402 346 (1401 | 1402 | 1403) )
blist = ( (+1|1)? 402 346 xxxx )
I then set up SP1's InboundCallRoute:
X_InboundCallRoute = {(Mwlist):ph},{(Mblist):sp1(14025551212; ui=$1)},{ph}
The first rule is white list, let friends phone to come to my phone. The second rule is black list, all other neighbor phone numbers are captured here, and forwarded to the directory assistant number 402-555-1212. Google Voice tells the caller "We can not complete your call. Please try again.", click, disconnected. If the incoming call does not match the first two rules, it passes to the last one, the phone.
My land-line phone (GV+OBi200) is so much quiter now.
This method is good if you've moved around and kept the old number so you have only a few old "neighbor" friends, making it easy to come up the white list.