in my application i should install one asterisk server to hold a group of VoIP PBXs, on the other hand it must has a gateway to PSTN, and SMS gateway;
the question is:
1- for the PSTN Gateway can it be connected to one line through a modem or i must have ISDN-PRA or some thing else
2- SMS Gateway, do i need an E1 connection with the operator or just a mobile phone SIM card is enough
3- where can i find documentation about this issue specially that i’m new to Asterisk
taking in considration that this is for a smal use and testing only; actually it is my miniProject in my university.