tyntec enables companies to integrate voice services into the core of what they do by acting as a gateway between PSTN (Public Switched Telephone Network) and VoIP (Voice over IP).
All access is realized via IP, without the hassle of worrying about the legacy telephony protocols. tyntec terminates and receives voice calls on your behalf by converting VoIP to TDM (Time Division Multiplexing) calls according to the SIP standard (SIP RFC3261, SDP RFC2327, RTP 3550). SIP is an industry standard defined by the IETF and enjoys widespread industry use.
This document describes the interface, depicted with a blue arrow, in the picture below: