A : a generally major channel or passage (for instance a chute or shaft) b : a circuit involving two telephone exchanges for earning connections among subscribers broadly : a generally Digital path in excess of which information and facts is transmitted (as involving Laptop or computer programs) A VoIP http://buzzgram.de/die-evolution-der-kommunikation-eine-einfuhrung-in-sip-trunking-voip-handys-softphones-und-voip-telefonanlagen/