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
Citel is The VoIP Migration Company™. We develop the world''s most comprehensive portfolio of network-edge products enabling enterprises to realize the cost and productivity benefits of IP telephony.