A network interface device that allows a user to simultaneously receive/send a plurality of calls from/to a telecommunications network by multiplexing/demultiplexing the calls on a single telephone line. The network interface device allows for the provisioning of an extra line on demand to the user for...http://www.google.de/patents/US6263063?utm_source=gb-gplus-sharePatent US6263063 - System and method for provisioning an extra line on demand and for selectively connecting calls with a plurality of devices
