Harald Welte's blog
   

RSS

Categories

Archives

Harald's Web
gnumonks.org
hmw-consulting.com

Projects
OpenBSC
gnufiish
deDECTed.org
OpenMoko
gpl-violations.org
gpl-devices.org
OpenEZX
OpenBeacon
OpenPCD
librfid
openmrtd
opentom.org
netfilter/iptables

Other Bloggers
Rusty Russell
David Miller
Martin Pool
Lawrence Lessig
Sirtaj Singh Kang
Jeremy Kerr
Atul Chitnis
Tim Pritlove
fukami
Michael Lauer
Stefan Schmidt
Kalyan Varma
David Burgess
Bradley M. Kuhn

Aggregators
kernelplanet.org
planet.netfilter.org
planet.openezx.org
planet.openmoko.org
planet.foss.in

Creative Commons License
Articles on this blog/journal are licensed under a Creative Commons Attribution-NoDerivs 2.5 License.


blosxom

       
Sat, 26 Apr 2008
First ASUS day of OpenTechSummit Taipei

As I might have indicated before, I have the pleasure of being invited to the OpenTechSummit 2008 in Taiwan. Two days ago, I was at the opening dinner. The problem of that dinner was the lack of attendees. There were loads of delicious (free, sponsored) food, but not even remotely enough people to eat it.

Today I had a bit of a problem finding the ASUS venue, since it was said to be at "exit 2" of the MRT station. Unfortunately it had two exits of that name, one on each side of the station :)

One presentation there I found particularly embarrassing was the one about the eePC SDK. First of all, I will ignore my thoughts about why you actually need such an SDK if it really is nothing more than a customized Debian Linux with Eclipse. But even then, why fly in a foreing speaker to do a click-by-click walk-thhrough on how to create a 'hell world' Qt program using eclipse?

My favourite of the day was definitely the presentation on the OpenPattern router board.

[ /linux/conferences | permanent link ]

Thu, 24 Apr 2008
Back to Taipei

After a break of almost six months, I'm back to Taipei. Obviously I now see everything from a quite different angle: I no longer work for OpenMoko, Inc., thus I actually have spare time here and can explore both the capital city as well as the country much better than before with that ever-growing OpenMoko workload.

However, the first day wasn't quite as relaxing as it should have been. First, the apartment key that was supposed to be with the guard of the apartment building accidentally was mixed up with some other key and got sent to the landlord.

A couple of hours later I discover that my Yamaha TW225 motorbike doesn't work anymore. First diagnosis: Battery is empty (not surprisingly). I try for like 15minutes to kickstart it, to no avail. Not even a single explosion in the engine. Then I tried to push it, and got it to a couple of explosions after which it died again. Further push-starting was prevented by the way-too-smooth floor of the parking garage, where the wheel just slides as soon as you release the clutch :(

Some disassembly revealed where the battery is (I don't know this bike at all, much opposed to my F650ST in Germany). The battery was severely short of acid/fluid, maybe somebody pushed the bike over and it leaked. Obtaining battery additive and refilling results in only 800mA charge current. I think it's dead. Now I'm in the process of ordering a new battery.

Let's hope the next couple of days are better than the start of this trip...

[ /personal | permanent link ]

Mon, 21 Apr 2008
Review of DORS/CLUC 2008 in Zagreb, Croatia

I've spent the last five days in beautiful Croatia - most of the time in its capital Zagreb. The local conference DORS/CLUC has been around for a couple of years, and in fact I've been at a previous incarnation three years ago.

It's a nice, small but great event. And in fact, for the invited speakers as myself it feels more like an all-inclusive holiday than a conference. The organizers went out of their way to make us feel at home, including a trip to the waterfalls of Plitvice national park (photos will be available shortly at my public photo album.

It was also great to spend some time with Alan Cox again, who to my surprise was also attending the event with two lectures. Hope his luggage didn't get lost again on his way home...

[ /linux/conferences | permanent link ]

Sat, 12 Apr 2008
Further studying of Abis protocols, moving towards implementation

The first quarter of 2008 is already gone, and I still haven't found all the time that I wanted to find to play with my BS11 base station[s].

However, I've spent quite a bit of time over the last couple of days further studying the GSM/3GPP 08.5x documents, as well as a thorough read through the mISDN source code.

GSM/3GPP 08.5x describe the layer1, 2 and 3 protocols of the Abis link between BSC (Base Station Controller) and BTS (Base Transceiver Station) in a GSM network. It's modelled on top of a E1 link in PCM30C configuration, i.e. TS0 is for CRC4 and synchronization, TS16 is used for the layer2+layer3 protocols, whereas the other time slots are used for transfer of the actual voice call data.

After looking at the various different driver options on Linux, I have determined that mISDN is the most promising and flexible architecture available. mISDN also has a layer0 + layer1 driver for the NT mode of the HFC-E1 card that I'm using. mISDN is great in a way that every layer is strictly separated from the other layer, and that at any layer parts of the stack can be implemented in userspace using library API.

Thus, I've started to write some mISDNuser based code to attach to the kernel-side hardware and lower-layer drivers. I'm not yet sure if the Q.921 (ISDN Layer2, also called LAPD) of the mISDN kernel side can be reused for Abis or not. The differences between standard Q.921 used on European ISDN and the Abis Layer2 are fairly small, so I hope to get it working with the existing LAPD code.

Unfortunately, I have paid work to take care of, so I will once again be distracted from this most interesting of my toy projects.

[ /gsm | permanent link ]

Report from FSFE FTF Licensing and Legal workshop

I'm on seven-hour train ride back from Amsterdam, where I've been attending the first Licensing and Legal workshop of the Freedom Task Force (FTF) of the Free Software Foundation Europe (FSFE).

While having a somewhat lengthy name, the FTF has been doing great work on bringing together a large group of legal and technical experts in the field of Free Software licensing. So far this was all 'virtual', happening on mailing lists.` The meeting in Amsterdam was the first of its kind, and was a huge success.

By the nature of the FSFE, most of the people were from Europe, though there were attendees from the US and even Australia, too.

There were many interesting and surprisingly interactive workshops. It was also a good opportunity to meet Armijn (the second half of gpl-violations.org) and Shane (full-time manager of the FSFE FTF), as well as many lawyers, both corporate legal counsel and from law firms.

The interest in Armijns presentation about gpl-violations.org and Till Jaeger's overview about the legal cases we've handled over the years in Germany were very well received and there was more interest and questions than the short time permitted.

What was really good for me to see is that large consumer electronics companies in Europe and the US are now implementing internal business processes to ensure GPL and other FOSS license compliance. They're also increasingly using very clear contractual language throughout their supply chain to minimize the potential risk of any "hidden" GPL surprises in products they source from OEM/ODM companies.

[ /linux/gpl-violations | permanent link ]

Fri, 11 Apr 2008
We don't do Advertisement on the netfilter.org homepage

For some reason, the amount of inquiries about companies who want to put ads on netfilter.org has significantly increased. Since the content of that site has not really changed much in the last (at least) four years, this sudden interest is somewhat surprising to me.

However, we are absolutely not interested in advertisements. I personally hate any form of advertisement, whether in print media, radio, TV, WWW or on billboards. In fact, advertisements are the reason for me to not watch any privately owned TV or radio stations for at least eight years.

So to all the advertising companies out there: Only over my dead body will there be any kind of banner ads on any of the websites of the projects in which I have anything to say.

[ /linux/netfilter | permanent link ]