osmo-e1d¶

osmo-e1d is an E1 interface deamon that is part of the Osmocom E1 interface driver architecture. It was primarily written for the icE1usb USB E1 adapter.

osmo-e1d acts as an interface between the hardware/firmware of the E1 interface on the bottom side, and applications wanting to use E1 timeslots on the top side.

osmo-e1d implements

• the USB protocol exposed by the no2e1 FPGA E1 core by @tnt, as used for example in the icE1usb device
• software HDLC by means of libosmocore
• multiplex/demultiplex from the 2048kBits/s E1 on the one hand side and the 32 timeslots of 64kBits/s

The interface towards applications is modelled to be compatible with DAHDI, that is to have one file descriptor per 64k E1 timeslot. Timeslots can either carry raw, unaligned bitstreams or HDLC frames.

In order to use osmo-e1d from applications, there is a small client-side library included: libosmo-e1d.

libosmo-abis contains an e1_input backend for osmo-e1d using libosmo-e1d.

Source code¶

The source code is available from gitea.osmocom.org

Public read-only access is available via

git clone https://gitea.osmocom.org/retronetworking/osmo-e1d

You can browse it via gitea: https://gitea.osmocom.org/retronetworking/osmo-e1d

Contributions are welcome via Gerrit.

Source code releases¶

You can find source code release-tarballs at https://downloads.osmocom.org/releases/osmo-e1d/

Binaries¶

For precompiled binaries, see existing package builds & apt repository at Latest Builds

Supported Software¶

• e1-prbs-test - Utility to test for bit errors on E1 lines using osmo-e1d or DAHDI

Further Reading¶

• Early Design Thoughts
• Osmo-e1d-pipe
• Vpair