The BXM-155 is a multiport ATM OC-3c/STM-1 interface card that uses custom application-specific integrated circuit (ASIC) technology, for the BPX 8600 Series, to deliver the industry's most advanced and reliable ATM networking features. It supports PVCs, SVCs, S-PVCs and MPLS LVCs (label VC). It provides redundancy protection for card as well as line via SONET/SDH Automatic Protection Switching (APS). Its high-speed connectivity takes ATM to new levels of efficiency and scalability.Enhanced models of the BXM-155 deliver the most advanced ATM switching and traffic management capabilities in the industry. These models extend scalability by doubling the connection density and cell buffers on selected models as well as providing future support for VC merging for large MPLS-based IP+ATM networks.