The 1202863L1 is a T1/FT1 Network Interface Module (NIM) for NetVanta 1000, 3000, and 4000 Series of access router, with a DSX-1 interface to user's voice equipment like a PBX. It provides a fractional or full T1 network interface for the NetVanta 1000, 3000, and 4000 Series, as well as, a DSX-1 interface for connecting voice equipment like a PBX.