The 56-Port DS-1/E1 card provides DS-1 interfaces as specified in ITU-T G.703 and Telcordia GR-499-CORE for a Digital Interface at 1.544 Mbps and E1 interfaces ITU-T G.703 for a digital interface at 2.048 Mbps.The card will support asynchronous mapping of 1.544Mbps into VT-1.5 according to GR-253 and byte-synchronous per NTT (DSM-L) and per TTC (JT-I431a) standards. The card supports asynchronous mapping of 2.048Mbps into VC-12 (to VC-4) according to ITU-T G.707. The module supports the auto-detection of frame format for DS1 and E1 signals. Each DS1 interface is provisionable to support B8ZS or AMI (Alternate Mark Inversion with no Zero Code Suppression) line coding. The card supports unframed 2.048 Mbps E1 and 1.544Mbps DS-1 signals and superframed (SF) and extended superframed (ESF) DS1 signals per G.704 and GR-499-CORE. Each E1/DS1 interface supports terminal and facility loopbacks. The DS1 ports are provisionable to be used as a source of system timing with synchronous status messaging (SSM) supported. The system will be able to re-time some of the DS1/E1 signals at the egress port interface. Line Build out is configurable as 0-131 feet, 132-262 feet, 263-393 feet, 394-524 feet, or 525-655 feet for DS-1 interfaces. The card supports a full suite of performance monitoring capabilities.