The question becomes: does anyone have the documentation released about the PACSAT protocols? If so, then I think an implementation would not be difficult, I don't remember the client side being overly complex. Therefore the corresponding server side would not be either.
see below... is from https://www.g0kla.com/pacsat/
- PACSAT Protocol Suite - An overview
- PACSAT File Header Definition
- PACSAT Broadcast Protocol Used for directory broadcast and all downloads
- PACSAT Broadcast Protocol Update 1 Errata
- PACSAT Broadcast Protocol Update 2 The case for OLD and NEW dates on directory entries
- PACSAT Broadcast Protocol Update 3 CL, BL file formats and the PBLIST destinations
- Pacsat Protocol: File Transfer Level 0 Only used for Uploading Files, ignore Download logic
- Pacsat Protocol: File Transfer Level 0 - Update
- PACSAT Data Specification Standards
- The legacy list of compression types
- The legacy list of file types.
Excellent, thank you. Reading those will be like meeting old friends.
Beside the PACSAT Broadcast Server, perhaps it might also be interesting to think about TCP/IP implementation.
However, because of the large round-trip time, some modifications are required..
But the good news is, that such protocols already exists.. like SACK..
We could even think about MQTT services, from which I'm a big fan...
MQTT allows implementing of an ChatBox.. I believe FB messenger is using MQTT protocol..
For another "unofficial" AMSAT project I was think about having an MQTT Broker on a LEO satellite
But this IoT technology might be even interesting via QO-100 with sophisticated Up- and Downlink modems.
Can be even a separate server in Bochum
25 years ago, I wrote my personal extension to the DOS program NOS from ka9q for transmitting the pacsat protocol for the db0bru digipeater.
As I remember it was not so complicated, but I cannot find the old source code.
I simple solution is only transmitting the files and directory information for the beacon without a possiblity to request files and holes.
I've just tried die use linux and send simple packtes with the right pid. That is simple just with a modified beacon program from the axtools software package.
Transferring a file can look like:
pacsatbeacon --fps <frames per minute> --pacfile <filename> <port> QST-1
--pacfile is a file to transfer packed with pacsat file header (pfh program).
The file id is read from the file header.
--fps frame per second, float. This must fit into the bandwidth of the channel.
With a litte bit more work the transfer of the directory will be possible with:
beacon --pacsatdir <spooldir> <port> QST-1
If you are still need such a program i can invenst a few days for this to complete at least the 1st form for the filetransfer.
Migration from old DOS code to linux is still in progress. But a first prototype is able to send directory broadcasts and files. G0KLA software is able to capture the broadcasts. First tests over the air will be possible. On problem exist. The G0KLA Software has fixed source callsigns an can only receive Falcon3 FST3.
G0KLA is a very accessible guy (I've been in touch in the past regarding PACSAT logfile formats). I am prety sure he could perhaps supply a special version for QO-100 experimenting...
You could try to contact him.