The test access system of the present invention is for use in a digital loop carrier communication system having at least first and second terminals connected by a digital transmission line. Each of the first and second terminals has a plurality of analog ports for analog signals and at least one digital...http://www.google.fr/patents/US4949355?utm_source=gb-gplus-shareBrevet US4949355 - Test access system for a digital loop carrier system
Test access system for a digital loop carrier system
