Initially we started to cover a couple of retronetworking topics at the OsmoDevCall, but it really made sense to run the pure retro related topics as a separate series of events. In October 2022, we forked the Retro Net working Call format from OsmoDevCall.

The format serves two major purposes:

  1. technical presentations about retronetworking relevant topics - ideally current/recent developments
    • can be pre-recorded to avoid any problems with technical setup, streaming, ...
    • should ideally have a Q+A session at their initial "airing" during one OsmoDevCall
  2. unstructured supplementary social event (USSE)
    • random chat in audio (optionally video)
    • not recorded, obviously

Not every RetroNetCall would necessarily need the two parts, but I think it would be great if we can make that happen.


Wednesday evening, 8pm CET (winter) / CEST (summer), every 1st Wednesday of the month

The next couple of events hence are:

  • Wednesday, July 3rd, 2024
  • Wednesday, August 7th, 2024
  • Wednesday, September 4th, 2024
  • Wednesday, October 2nd, 2024

Venue / Platform

We are currently using infrastructure of KNF, a German non-profit internet organization of which laforge is a member.

The URL to join the meeting is

There currently is no password or authentication, we try to welcome anyone. If this turns out to be a problem, we might lock it down in the future, let's hope that's not required.

Video Recordings of talks

The recording of the technical presentation are made available. The recordings can be found

Topics (for the "presentation" part)


This is a wishlist of future topics for the "presentation" part:

Topic Possible Speaker Tentative Date
Token Ring
Frame Relay
The X.25 Packet Switched Network
Analog Telephone Modems and towards a 2022 OSHW softmodem laforge + tnt
ISDN: Differences DSS1 <-> 1TR6
X.31: Two flavours of X.25 over ISDN
H.221: The first step into ISDN video calls (H.320)
HDLC World Domination (history of HDLC)
EWSD Introduction/Overview
S12 Introduction/Overview
Nokia TCSM2, a bank of TRAUs with E1 interfaces: Part 2, working state falconia


We'll move the events from the above table to here once they have happened.

Topic Speaker Date Video
TDM, E1, PDH, SDH, STM-1 and Pseudowires laforge 2021-11-12 H.264 VP9
iceE1usb in practice tnt 2021-11-12 H.264 VP9
Retronetworking: V5 interfaces in ISDN/PSTN laforge 2021-12-28 H.264 VP9
Osmocom Community TDMoIP (OCTOI) laforge 2022-04-29 H.264 VP9
OCTOI project status update laforge 2022-11-09 H.264 VP9
ISDN B-Channel protocols (X.75, V.120, V.110, T.70, ...) laforge 2022-12-07 H.264 VP9
Datex-L: The German CSPDN (Circuit Switched Public Data Network) laforge 2023-02-01 H.264 AV1
Introduction to the X.21 synchronous serial interface laforge 2023-03-01 H.264 AV1
E1: The analog side (part 1) tnt 2023-05-04 H.264 AV1
Teletex: The brief abandoned step between Telex and Telefax laforge 2023-06-07 H264 AV1
Teletext: A digital medium transcending a factor of 10⁶ in technical progress casandro 2023-07-05 H264 AV1
A tour of DIVF, our OCTOI central office using yate, dahdi-trunkdev and more laforge 2023-12-06 H264 AV1
Decoding G4 fax protocol traces laforge 2024-03-06 TBD
Nokia TCSM2, a bank of TRAUs with E1 interfaces: Part 1, initial examination of the hardware falconia 2024-06-05 Slides TXT Slides PDF

Code of Conduct

The existing Code_of_Conduct of our previous physical / on-site / presence meetings applies.

Updated by laforge 9 days ago · 65 revisions

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