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Tue, 31 May 2011
Starting to investigate old Motorola Dimetra EBTS

Together with some friends, we have managed to get our hands on some ancient (1997) Motorola Dimetra TETRA equipment. Specifically, this includes the Base Radios (BR) and the TETRA Site Controller (TSC).

We haven't yet managed to put everything up in the wiki, but you can watch our progress at the Dimetra_EBTS page on http://tetra.osmocom.org/ as well as it's sub-pages.

It's going to be a big challenge to put all that equipment to some good use. Success is probably defined in terms of running your own small TETRA network with such an EBTS but without any of the Motorola Dimetra core network infrastructure (SwMI, basically the same thing we did for GSM with OpenBSC.

The big conceptual difference to GSM here is: In GSM, the internal protocols (A-bis, A, ...) are all publicly specified. There are vendor-specific dialects, but those are relatively easy to figure out. In TETRA, the ETSI only specified the air interface, but not the interfaces between the wired components of the network. This leaves pretty much everything else proprietary :(

So if anyone has any information (installation manuals, service manuals, provisioning software, protocol specifications, ...) or experience with configuring or maintaingin this equipment, I would be very happy if you could drop me a message.

[ /tetra | permanent link ]

Interview with German newspaper taz about gpl-violations.org work

There has been an interview for (at least) the online edition of the German newspaper taz - die tageszeitung. If you understand German, you can read it here.

By coincidence, I'm a subscriber to that very same newspaper for more than 10 years ;)

[ /linux/gpl-violations | permanent link ]

Mon, 30 May 2011
HTC announcement about no more locked-down phones

As it has been covered at various news site, HTC has apparently announced that they will not be shipping Android phones with locked-down bootloaders.

If this is really true, it would mean that more people not only have the theoretical freedom to run modified versions of Linux (granted by GPLv2), but also the practical freedom. If there is no cryptographic restriction on only booting HTC-supplied versions of the Linux kernel (and other software), this is good news!

It comes as a bit of surprise though. "Traditionally", HTC is known for behaving unfriendly towards the community. Not only due to their source code releases being constantly too late, but also due to the fact that their phones were some of the first to use cryptographic signatures to keep people from installing their own versions of Linux (and Android).

The other surprising move has come from Motorola, who probably has the longest tradition of shipping Linux-based phones (in various degrees of GPL compliance), but then using technical means to deprive their customers of the Freedoms the GPL wants to grant to them, i.e. the freedom to run modified versions of the Software (Linux in this case). They did this with the later models of the EZX range, with their MAGX phones, as well as now with their Android phones over the last couple of years. So it was very puzzling to see the same Motorola announce a 180 degree turn in policy at least for their Xoom tablet.

Also, in recent news, Sony Ericsson made a similar announcement that at least some of their Xperia models can be bootloader unlocked.

It's really striking. During the least seven years, I used to be involved in a number of projects that tried to enable the user of mobile smartphones to have the full source code for (at least) the Linux kernel, and to be able to modify, tinker and re-program it any way they want. Now some of the vendors seem to be moving in the right direction.

What's sad is that Samsung is not capitalizing on their potential here. They have always had very timely and complete source code releases for all their Linux based phones at http://opensource.samsung.com/, and they have very rarely tried to lock any of the bootloaders. I don't know if this is intentional or not. But now the other vendors are getting good PR for stopping to do something that (to my knowledge) Samsung has not done, at least not to the extent of the others.

In any case, I still think the Nexus S is the best choice for anyone who wants to have a developer friendly device. It is fully supported in the main AOSP tree, everything in the kernel is GPLv2, and those binary userspace blobs that are required are distributed independently at https://code.google.com/android/nexus/drivers.html so they can be integrated into custom builds. This is by no means perfect, but the best compromise that seems available at this point. I still don't understand why the userspace drivers for the GSM/3G modem, Wifi, Bluetooth and GPS would need to be proprietary. Or even the NFC par, it's sort-of ridiculous to have that proprietary with Free Software RFID stacks like libnfc and librfid around...

[ /linux/mobile | permanent link ]

Fri, 06 May 2011
Apple not providing LGPL webkit source code for latest iOS 4.3.x

As some people may know, next to a plethora of BSD licensed code, Apple is using some LGPL licensed code in their iPhone products.

So far, it seems they have always provided the respective source code in a timely manner for each and every release they have made on a website www.opensource.apple.com.

However, in recent months it seems they have deviated from that policy for unknown reasons. As my friend and webkit developer zecke has blogged, Apple has stopped to release their webkit source code with iOS release 4.3.0. The corresponding website simply states: "coming soon".

iOS 4.3.0 was released on March 10, 4.3.1 on March 25, 4.3.2 on April 14 and 4.3.3 on May 4. For all of those releases, no source code has been published.

It cannot be a simple oversight, as multiple inquiries have been made to Apple by interested developers. However, the source code yet has to be released.

I think it is time that Apple gets their act together and becomes more straight-forward with LGPL compliance. It is not acceptable to delay the source code release for 8 weeks after shipping a LGPL licensed software. Especially not, if you have already demonstrated in the past that you are well aware of the obligations and have a process and a website to release the corresponding source code under the license conditions.

[ /linux/gpl-violations | permanent link ]

Mon, 02 May 2011
Jounrees Logiciels Libres / ENSA Tetouan, Morocco

I've been invited to Tetouan, Morocco by the organizers of the second incarnation of the Journees Logiciels Libres. Tomorrow I'll have the pleasure of presenting about Free Software projects related to GSM, including OpenBSC and OsmocomBB.

The organizers have done a great job in caring about the foreign speakers (who include Richard Stallman and myself).

I've been listening to various talks by RMS RMS over the last 16 years or so... but right now I'm listening the first time to him giving a French presentation.

Overall, this trip has done more to improving my understanding French than anything else in a long time. I once had 4 years of French from 1st to 4th grade in school, but never really continued with it. However, what I remember, combined with my knowledge of Portuguese (and even English) is sufficient to e.g. understand all of the French language slides that have been presented at this conference. However, most spoken French is too hard to understand for me.

One striking observation is the apparently much higher percentage of women taking a communications or computer engineering degree here than what I'm used to in Germany or the so-called western world. It reminds me of India where you have the feeling that almost 50% of the IT related students are female. It would still be interesting to see some scientific research why the supposedly open and anti-discriminating, women-rights-embracing 'western world' is seeing less women taking up engineering studies...

[ /linux/conferences | permanent link ]