OsmoDevCon 2017 Review

After the public user-oriented OsmoCon 2017, we also recently had the 6th incarnation of our annual contributors-only Osmocom Developer Conference: The OsmoDevCon 2017.

This is a much smaller group, typically about 20 people, and is limited to actual developers who have a past record of contributing to any of the many Osmocom projects.

We had a large number of presentation and discussions. In fact, so large that the schedule of talks extended from 10am to midnight on some days. While this is great, it also means that there was definitely too little time for more informal conversations, chatting or even actual work on code.

We also have such...

Book on Practical GPL Compliance

My former gpl-violations.org colleague Armijn Hemel and Shane Coughlan (former coordinator of the FSFE Legal Network) have written a book on practical GPL compliance issues.

I've read through it (in the bath tub of course, what better place to read technical literature), and I can agree wholeheartedly with its contents. For those who have been involved in GPL compliance engineering there shouldn't be much new - but for the vast majority of developers out there who have had little exposure to the bread-and-butter work of providing complete an corresponding source code, it makes an excellent introductory text.

The book focuses on compliance with GPLv2, which is probably not too surprising...

OsmoCon 2017 Review

It's already one week past the event, so I really have to sit down and write some rewview on the first public Osmocom Conference ever: OsmoCon 2017.

The event was a huge success, by all accounts.

We've not only been sold out, but we also had to turn down some last minute registrations due to the venue being beyond capacity (60 seats). People traveled from Japan, India, the US, Mexico and many other places to attend.

We've had an amazing audience ranging from commercial operators to community cellular operators to professional developers doing work relate to osmocom, academia, IT security crowds and last but not least enthusiasts/hobbyists, with whom the project[s]...

Making a bench PSU out of a cheap buck/boost module off the web

Modding a LTC3780 board to use different pots, toroidal transformer rewinding and a bit of bodging gone wrong.

Things you find when using SCTP on Linux

Observations on SCTP and Linux

When I was still doing Linux kernel work with netfilter/iptables in the early 2000's, I was somebody who actually regularly had a look at the new RFCs that came out. So I saw the SCTP RFCs, SIGTRAN RFCs, SIP and RTP, etc. all released during those years. I was quite happy to see that for new protocols like SCTP and later DCCP, Linux quickly received a mainline implementation.

Now most people won't have used SCTP so far, but it is a protocol used as transport layer in a lot of telecom protocols for more than a decade now. Virtually all...

SIGTRAN/SS7 stack in libosmo-sigtran merged to master

As I blogged in my blog post in Fabruary, I was working towards a more fully-featured SIGTRAN stack in the Osmocom (C-language) universe.

The trigger for this is the support of 3GPP compliant AoIP (with a BSSAP/SCCP/M3UA/SCTP protocol stacking), but it is of much more general nature.

The code has finally matured in my development branch(es) and is now ready for mainline inclusion. It's a series of about 77 (!) patches, some of which already are the squashed results of many more incremental development steps.

The result is as follows:

General SS7 core functions maintaining links, linksets and routes

xUA functionality for the various User Adaptations (currently SUA and M3UA...

Мои маленькие реле: Brainfuck компьютер это магия

Введение

Давным давно, когда вокруг все было большим, а я маленьким, читал я книгу Войцеховского «Радиоэлектронные игрушки», горя желанием воплотить в жизнь те или иные описанные в ней устройства. Так, в уже тоже далеком 2008-м году, из нескольких десятков электромагнитных реле было собрано 4-разрядное АЛУ (РЦВМ1 — Релейная Цифровая Вычислительная Машина — версия 1) способное складывать и вычитать. И задумал я тогда — а что если собрать существенно большее количество реле и построить полноценный релейный компьютер? На неспешную сборку реле то здесь то там до требуемого количества ушло всего 8 лет, и я начал творить.

Разрешите представить Вам свой проект по...

О технических аспектах внешней и внутренней мотивации

Аннотация: В статье рассматривается личность учащегося в свете теории автоматического управления, где внешняя и внутренняя мотивация являются управляющим и возмущающим воздействием. Рассматриваются технические аспекты мотивации, предлагаются возможные методы повышения мотивации учащихся.
Одной из проблем текущего образования является низкий уровень мотивации учащегося. Не секрет, что большая часть выпускников престижных (и не только) вузов идет работать не по полученной специальности. Основная причина, по мнению авторов, кроется в том, что за время обучения учащийся не был достаточно заинтересован в предмете обучения. В результате уровень его внутренней мотивации, после выхода из стен учебного заведения недостаточен для того, чтобы устроиться на работу, где могли бы быть...

OsmoCon 2017 Updates: Travel Grants and Schedule

April 21st is approaching fast, so here some updates. I'm particularly happy that we now have travel grants available. So if the travel expenses were preventing you from attending so far: This excuse is no longer valid!

Get your ticket now, before it is too late. There's a limited number of seats available.

The list of talks for OsmoCon 2017 has been available for quite some weeks, but today we finally published the first actual schedule.

As you can see, the day is fully packed with talks about Osmocom cellular infrastructure projects. We had to cut some talk slots short (30min instead of 45min), but I'm confident...

Upcoming v3 of Open Hardware miniPCIe WWAN modem USB breakout board

Back in October 2016 I designed a small open hardware breakout board for WWAN modems in mPCIe form-factor. I was thinking some other people might be interested in this, and indeed, the first manufacturing batch is already sold out by now.

Instead of ordering more of the old (v2) design, I decided to do some improvements in the next version:

add mounting holes so the PCB can be mounted via M3 screws

add U.FL and SMA sockets, so the modems are connected via a short U.FL to U.FL cable, and external antennas or other RF components can be attached via SMA. This provides strain relief for the...