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 |
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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 ]
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 |
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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 ]
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 |
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