A call shop is a business that provides physical phones for the purpose of making long-distance telephone calls. There are two main types of call shop payment methods; prepaid and postpaid.
Concerning practical implementation, the VoIP gateways have proven to be the best. Many companies are successfully using the IP telephony thanks to its two main characteristics
Decrease in international and long distance call cost expenditures
Stable communications between company’s offices throughout different cities and counties