Access router for Internet access, public and private Frame Relay, leased line connections, and Virtual Private Networking (VPN). Interchangeable network interface module (NIM) slots for 56/64K, T1/FT1, Serial, or T1/FT1 w/DSX-1 NIMs. Supports E1 for global applications. Built-in DSU/CSU protects circuit. Auto-sensing 10/100BaseT interface to accomodate mixed Ethernet environments. Command Line Interface (CLI) mimics de facto industry standard. Optional DSX-1 interface available for voice connectivity to a PBX.