what is EMTA modem
VoIP modem. A device that combines a DOCSIS cable modem and analog telephone adapter. Officially called an embedded-multimedia terminal adapter (E-MTA), the modem provides the data interface to the cable company, and the telephone adapter provides the voice over IP (VoIP) interface for one or more analog telephones.oIP and Internet Modems. The coaxial cable from the cable company is split (bottom) and wired separately into the VoIP modem and cable Internet modem. One analog phone line from the VoIP modem goes into a small PBX that also connects to three SIP lines for this small business. 1  Facebook.