The ADTRAN FSU is a stand-alone Frame Relay access device (FRAD) that provides a cost-effective means of transporting multi-protocol data over frame relay networks. The ADTRAN FSU provides an easy-to-use interface for customers migrating existing services or developing new applications for operation over Frame Relay networks.The FSU provides two independent DTE interfaces for connecting non-Frame Relay devices to the Frame Relay network. The DTE ports support synchronous data rates from 2.4 to 512 kbps and asynchronous from 2.4 to 38.4 kbps. Both EIA-232 and V.35 physical interfaces are available for connection to the customers' DTE equipment. The FSU's concentrator feature allows the connection of two Frame Relay devices to a single Frame Relay network interface. The FSU may be purchased with an integral 56/64 DDS DSU/CSU or an external DSU/CSU may be connected to the DCE interface. Network speeds up to 512 kbps and both EIA-232 and V.35 physical interfaces are supported through the DCE port. The FSU supports SNA, SDLC, Bisync, SLIP, IP, PPP (both synchronous and asynchronous), Frame Relay, BOP, and asynchronous protocols. The DTE ports can be configured independently, providing support for multi-protocol applications.This FSU (Experess 5110) is equipped with an integral 56/64 DDS DSU/CSU. Network speeds up to 512 kbps and both EIA-232 and V.35 physical interfaces are supported through the DCE port.