In this article SIP trunking refers to the connection of a company’s (SIP or ISDN) PBX, and underlying VoIP VPN if any is used, to public networks through the SIP protocol. In that sense, SIP trunking is a replacement for ISDN (mainly PRI) and is first and foremost a voice service. A SIP trunking service thus offers end customers first the customers’ phone numbers (portability of existing numbers or new phone numbers). But please note that since the revenues for these are based mostly on regulated one-off payments, they were therefore not considered in the subsequent quantification in this article. Secondly and most importantly SIP trunking offers voice channels for simultaneous incoming and outgoing calls with some standard features such as fax, DTMF (Dual-tone multi-frequency signalling), CLIP/CLIR (Calling Line Identification Presentation / Restriction), etc., as well as the accessibility of emergency numbers, of (almost) all fixed and mobile numbers worldwide and of most special/premium numbers.
Overview of retail providers in Germany
Overview of retail offers in Germany
Market drivers and obstacles
Outlook - Forecasts