Patent ID: 6356638
Filing Date: 2002-03-12
Classification: H04K

Abstract:
A wireline interface for communicating between a digital subscriber unit and an analog network, the wireline interface comprising:a digital interface for establishing an encrypted digital link with the digital subscriber unit through a digital communication network, receiving a network number of a called party from the digital subscriber unit over the encrypted digital link, and receiving encrypted digitized voice from the digital subscriber unit over the encrypted digital link; a security module for decrypting the encrypted digitized voice providing decrypted digitized voice; a transcoder for converting the decrypted digitized voice to analog voice suitable for transmission through the analog network; a network interface for establishing a connection with the called party through the analog network and providing the analog voice to the called party; wherein the wireline interface is coupled between the digital communication network and the analog network, and wherein the digital interface receives a request to initiate the connection with the analog network initiated by the digital subscriber unit, the digital subscriber unit providing a number of the wireline interface to the digital communication network; the wireline interface includes a controller for causing the digital interface to establish the encrypted digital link; wherein the controller includes means for causing the digital interface to establish a unencrypted digital link with the digital subscriber unit prior to establishing the encrypted digital link, the digital subscriber unit communicating clear voice over the unencrypted digital link; and wherein the controller has means for receiving a request to communicate secure voice and prior to the digital interface establishing the encrypted digital link, the controller receives the request to communicate secure voice, and subsequent to establishing the encrypted digital link instructs the security module to decrypt received encrypted digitized voice, and instructs the transcoder to provide the analog voice.