In reply to a few points:
1) Yes, must be in the phone and phone must be working. As part of the porting process GV will make one phone call to the number being ported (i.e., the phone the SIM card is in), which you must answer and must enter a verification code that GV gives you on the screen when you do the port. Total usage is under one minute. You'll never get past this point unless you answer the call.
2) Don't know.
3) Does not have to be prepaid. You can for example take the working SIM card out of a working T-Mob phone, insert the new SIM associated with the ported landline number, and receive the GV call that way. T-Mob SIM cards come in different sizes (formats) so the SIM card you use must match the size the phone uses.
Quote from: johnpane on January 14, 2013, 07:43:33 PM
QuoteHowever, go search the Google Voice Product Forums and the DSL VoIP forum for explanations of how BandWidth.com is the third party provider Google uses to 'port numbers' to GV. BandWidth.com (or whatever third party) must have a presence in the central office before a port is started, not afterwards.
I did read some of those posts this afternoon. The main gist of the ones I found are that GV gets its numbers (the ones it issues) via Bandwidth.com and Level 3. There was an oblique reference to this having implications for porting, but I have to admit I had my doubts when I read that part. It seems outside the spirit of LNP for providers to be required to have a physical presence everywhere a number might be coming from. (Of course, one should not discount the potential for absurd regulations.) Moreover, it doesn't seem to make sense for the internals of the phone system to require anything at the original number's location for LNP. Everything about LNP should be able to be accomplished through centralized databases that map numbers to their currently-assigned switches.
Landlines and central offices and area codes are a highly regulated industry, so what makes sense is not always the driving factor.
Call flow is explained here on the website of this quasi-regulatory body for all LNP in the US:
http://www.npac.com/number-portability/how-lnp-works. I read it to mean all calls to a ported number do in fact flow through the CO switch where the number was 'born.'