A method and apparatus for providing analog telephony services over a digital subscriber loop access system is presented. Digital subscriber loop technologies including Asymmetric Digital Subscriber Loop (ADSL) leave existing POTs services undisturbed by utilizing spectrum above the POTs band for data...http://www.google.com.au/patents/US6208637?utm_source=gb-gplus-sharePatent US6208637 - Method and apparatus for the generation of analog telephone signals in digital subscriber line access systems
