A group of users can be created with a purpose of receiving voice announcements through the speaker of a telephone set, but it has to be in the waiting mode.
Voice of IP of VoIP technology, is the one which completely changed the telecommunications market by transmitting voice over the Internet. During past several years it expanded in such a way that right now it covers each and every corner of the world and it became the new standard of telecommunication. Nowadays there are plenty of companies offering different kinds of services and devices.