spabula

Sort of new to this so I am trying to figure this all out. I have Voip service provider ( Sunrocket ) which doesn't release any server info. Can I just use their converter (voip to PSTN) and then use an FXO adapter to convert back to my network for the incoming line? Sounds kind of half @ssed but I need to keep this number and they are giving me a hard time about porting it to Broadvoice. Anyone have any better suggestions? Brenden