VPN-UPLINK - Encyclopedia: ISDN
Integrated Services Digital Network (ISDN) is a type of circuit switched telephone network system, designed to allow digital (as opposed to analog) transmission of voice and data over ordinary telephone copper wires, resulting in better quality and higher speeds, than available with analog systems. More broadly, ISDN is a set of protocols for establishing and breaking circuit switched connections, and for advanced call features for the end user.
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "ISDN".