A communication system providing telephony communication across combined circuit switched and packet switched networks, such as a telephone network and the Internet, which are connectable to terminals, such as telephones and computers, for selective communication therebetween. The communication system...http://www.google.es/patents/US6295292?utm_source=gb-gplus-sharePatente US6295292 - Inbound gateway authorization processing for inter-carrier internet telephony
Inbound gateway authorization processing for inter-carrier internet telephony
