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
BT&T TELECOM GROUP CORPORATION is a Delaware, USA company incorporated in 1999. BT&T`s vision is to be a key player in the burgeoning telecom horizon, most especially in the Americas and Asia-Pacific countries.