FXO stands for foreign exchange office. An FXO port is an interface that connects your Plain Old Telephone Service (POTS) line to a VoIP adapter. Traditional telecom operator phone lines or analogue PBXs are connected to IP telephony networks using FXO VoIP Gateways, which offer a range of options such as 4, 8, and 16 FXO ports. These FXO gateways are essential for bridging conventional telecom systems with modern VoIP networks. By connecting your PBX system to a VoIP system, FXO Gateways allow users to make and receive calls using traditional analog phones while benefiting from the advanced features and cost savings of VoIP technology.

FXS stands for foreign exchange subscriber. An FXS port is used to connect station devices such as phones or PBX systems to a VoIP adapter. FXS VoIP Gateways are reliable and cost-effective solutions for integrating analogue phones, fax machines, and legacy PBX systems with IP PBX and IP phone networks. The DAG series of gateways offers a wide range of configurations, from 1 to 128 FXS ports and 4 to 32 FXO ports, including hybrid models like 4FXS4FXO and 8FXS8FXO. These gateways are widely adopted by telecom operators, service providers, and businesses to facilitate a smooth transition to VoIP technology.