Adtran NetVanta T1/FT1+DSX-1 Data Networking Model Overview
A Network Interface Module (NIM) that terminates a full or fractional T1 and also supports an additional DSX-1interface to drop-off voice traffic to a PBX.
Adtran 1202863L1 Data Networking Overview
NetVanta T1/FT1 + DSX-1 Network Interface Module (NIM) is for NetVanta 1000, 3000, and 4000 Series of access router, with a DSX-1 interface to user's voice equipment like a PBX.