A call shop is a privately owned business where customers can make local and international calls at discount / competitive rates. It can be situated in key locations in a city or in specific places such as universities, hotels, supermarkets, restaurants, schools etc. The revenue of a Call shop will depend on the amount of phone time generated by the customer from using the calling facility / Call booth.

VoIP (Voice over Internet Protocol) gives the ability to perform phone calls by using the Internet. This saves considerable amount of costs. With VOIP cheap international calls can be easily achieved. This offers the Call shop owner a great advantage as well as the possibility for greater profit. To be able to perform VOIP calls a partnership has to be established first with a VOIP gateway vendor.

The primary main advantage of VoIP over PSTN lines is cost ,it's much cheaper

VoIP gateways are devices that take analog voice signals and convert them to IP for transport over the LAN or WAN.