olemus
IP-võrku telefonivõrguga liidestav seade
= a hardware device that converts telephony traffic into packets of data for transmission over a IP-network

ülevaateid
https://www.techopedia.com/definition/25881/voice-over-internet-protocol-gateway-voipgateway
https://en.wikipedia.org/wiki/VoIP_gateway
http://www.3cx.com/pbx/voip-gateway/
http://www.voipsupply.com/overview-of-voip-gateways