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I’ve been interested in Plan 9 for some time now, though never tinkered with it in a significant depth. It may not be the most practical OS for daily activities, but it always sounded like a system worth studying for all the groundbreaking concepts it introduces and eventually gets adapted by other system. But I haven’t really expected it to be so much simple in source form. After all, it’s a research system; it should be full of incomprehensible coding trickeries, right?

Okay, that was obviously a trick question. But here is what’s made me really interested in Plan 9: Having a first glance in the source code of the cat utility and comparing it with what I’m running on my computer.

apt-get source 9base coreutils && emacs 9base*/cat/cat.c coreutils*/src/cat.c

Elegance and simplicity do go hand in hand.

Now, I have a new reason to learn the ways of Plan 9.

This is a duplicate of my post on freetard.net.

I will do a talk about Free Software GSM implementations at the Free Software Foundation Europe‘s Berlin meeting on Thursday, December 9th, next week. It will start at 19:30 in the Newthinking Store.

Here’s the abstract of the presentation:

GSM is the most ubiquitous mobile telephony platform in the world, and chances are you are carrying a GSM-capable device with you everywhere you go. Yet, practical implementations of GSM are shrouded in mystery. Their inner-workings are known only to a small cabal of companies away from public and commercial scrutiny. However, there’s hope on the horizon. In this talk, we’ll have an overall look at the state of Free Software GSM implementations and discuss what they could mean for the hacker and the common man in practice.

The talk will be aimed at those without any prior knowledge of GSM protocols, and I will not refrain from using crude oversimplifications to make my points.

You have gotten used to the idea of Android and Meego? Let’s see what you’ll think about the possibility of Free Software handling what your cell phone is primarily made for.

Three days after applying, I got my Flattr invitation. For those who haven’t heard about it before, Flattr is a web micropayment platform. From The Flattr story:

Flattr was founded to help people share money, not only content. Before Flattr, the only reasonable way to donate has been to use Paypal or other systems to send money to people. The threshold for this is quite high. People would just ignore sending donations if it wasn’t for a really important cause. Sending just a small sum has always been a pain in the ass. Who would ever even login to a payment system just to donate €0.01? And €10 was just too high for just one blog entry we liked…

You can use it to send and receive donations for any content you create. It, at least in theory, is especially useful for small payments. There isn’t an awful amount of content online supporting Flattr yet and the service itself is still in beta release, but it looks quite promising.

I activated my account by loading a small amount of money to my account and integrated it to my PyBlosxom flavour, so it automatically submits every blog post to Flattr. We’ll see how it goes.

I have been watching the Free Software tinkerers’ much needed approach to cellular phone networks for the past few years, albeit from a distance. Cellular telephony seems to be the biggest network implementation (bigger than the Internet in means of user base) that has been surprisingly closed to inspection and experimentation despite its age. Lately, I’ve started actively getting informed about GSM network protocols and their free implementations such as OpenBTS and OpenBSC. Both projects provide very promising opportunities for various scenarios. However, even if the two projects are combined with a free mobile operating system, one still wouldn’t have control on a very important part of his digital telecommunication. This is because the client side (i.e. the mobile phone) of the GSM connection would still be handled by proprietary chipsets whose innerworkings are unknown and out-of-reach.

About two months ago, Harald Welte announced a project called OsmocomBB which intends to close what might be called the missing link between the free GSM network implementations and the free mobile phone operating systems. When accomplished, the projects aims to have a fully functioning and free GSM baseband software stack in the mobile phone.

What I wanted to share was a paper titled Anatomy of contemporary GSM cellphone hardware released by Harald Welte today. Even though most of the concepts are still above my head, I very much enjoyed having a concise overview of all the processes going on in a phone. A tip for beginners: Print out the article if you can. It is bound to host a bunch of small side notes as you research around and come back to it.

Here are two paragraphs from the ending personal rants section to whet your appetite:

The GSM industry is one of the most closed areas of computing that I’ve encountered so far. It is very hard to get any hard technical information out of them. All they like to spread is high-level marketing information, but they’re very reluctant when it comes down to hard technical facts on their products.

All the various vendors do more or less the same. The fundamental architecture of a GSM baseband chip is the same, whether you buy it from TI, Infineon or from MediaTek. They all cook with water, like we Germans tend to say. The details like the particular DSP vendor or whether you use a traditional IF, zero-IF or low-IF analog baseband differ. But from whom do they want to hide it? If people like myself with a personal interest in the technical aspects of mobile phones can figure it out in a relatively short time, then I’m sure the competiton of those chipset makers can, too. In much less time, if they actually care.

Very exciting times are awaiting us.