I am planning on making a VOIP network for myself that will use a server running Asterisk. I was wondering how I would connect it to the PSTN so I can call anyone. I will be using the VOIP network just for myself and not trying to sell it to other people. No one else will be using it except for me. I heard I can use a FXO gateway which is a physical device that acts as a bridge between my network and the PTSN. Is that what I need? Please explain step by step what I would need to do and also include what I would need to buy and the cost.