VOIP has caught my interest today as it seems to be a great solution for somebody who travels frequently and needs to make cheap/free calls from wherever.
I know I can setup my own PBX server with something like Asterisk, but where I am getting hung up at is the service itself. A lot of the documentation out on the web states that you need both the VOIP PBX AND a subscription to a VOIP provider (For a VOIP phone number).
Isn't setting up an Asterisk box essentially providing the VOIP service yourself? Is the VOIP subscription just for the phone number?