The Osmocom icE1usb is a USB-to-E1 adapter, permitting legacy E1 interfaces to connect to modern computers. E1 (sometimes also called primary rate interfaces) were used for ISDN, Frame Relay, ATM, GSM Abis back-haul, TETRA back-haul, SS7 and many other telecommunications use cases.

icE1usb is a fully open source hardware (OSHW), open sourec gateware, firmware and host software project.