open-ondd

An open source file decoder for the Othernet data broadcast.

This is an open source file decoder for Othernet which aims to provide an open source alternative to ondd. This software is the result of a third-party reverse-engineering effort: https://github.com/daniestevez/free-outernet

With open-ondd you can receive the files and time packets that are broadcast by the Othernet file broadcast service.

open-ondd.py receives UDP packets in real-time from a designated UDP port. open-ondd.py recovers the files and time packets that are transmitted by Othernet and relayed over UDP. It also prints some interesting debug info.

Things that are not implemented/supported:

• X.509 signature checking. The file announcements of the Othernet file service are signed with the Othernet X.509 certificate to prevent spoofing.
• Using the time packets to set the system time.
• Automatic decompression of received files. Previously, most files sent by the Othernet broadcast were .tar.bz2 files. ondd extracts those files automatically.

Dependencies

To install all dependencies just run: pip3 install -r requirements.txt

• crcmod
• zfec

Sample KISS files

You can use some sample KISS files for testing.

About LDPC decoding for files

LDPC decoding has been implemented by George Hopkins by reverse engineering ondd.

The performance of open-ondd regarding FEC and LDPC decoding should be the same as the performance of ondd.