A telecommunication system is described that has an interface and multiple lines, such as T-1 lines. The multiple lines include at least one service line and at least one spare line. The interface comprises a bus across the service line and spare line and a common controller. The bus includes switches...http://www.google.fr/patents/US5509065?utm_source=gb-gplus-shareBrevet US5509065 - Dual span monitoring system for maintenance shelf control
Dual span monitoring system for maintenance shelf control
