I just realized how easy it is to cut off one of Google’s tentacles throughout the web. This is a WordPress blog and I used the Ultimate Google Analytics plugin to keep track of the number of visitors, where they come from (referer, not geo-location), keywords and so forth.
Google Analytics is just one of the many tentacles, Google spreads throughout the web. There is the Google Fonts API, there is Google Hosted Libraries and probably numerous other things that I am not aware of. Visitors to websites that include any one of these Google services will always contact one or multiple Google servers, thus identifying themselves (to some degree).
So I uninstalled the Google Analytics plugin, deleted my Google Analytics account and installed the WordPress Statistics plugin instead. It works flawlessly so far. I can recommend it.
Mere users of the web can monitor and block these tentacles as they browse the web through a Firefox add-on called Disconnect. I can recommend this plugin as well.
Let’s work together to make the web a less centralized, more private place for everyone. Let’s try to exclude large corporations from our interactions between each other. It is probably none of their business and certainly should not be their business.
I just discovered scikit-image – an image processing toolbox for the python programming language. The project appears to be very active and under heavy development. I have been looking for a while for ways to replace my scripts that rely on the Matlaband this seems to do the trick. I’m especially excited about the libraries functionality to measure region properties. This will come in very handy. I have either been sleeping under a stone or this project is not very well known. Let’s change that. Go check out scikit-image!
It looks like Nvidia is slowly but steadily abandoning OpenCL – their OpenCL examples are not included in the 5.0 SDK anymore and the links on their OpenCL webpage are dead. It is not clear if this is an oversight or intentional. With the recent introduction of the Intel Xeon Phi, an accelerator that supports OpenCL, this could be a strategic move on Nvidia’s part.
I’ve created a github repository that contains all Nvidia OpenCL examples from CUDA version 4.2.9. Please note that it currently contains only the Linux examples. Feel free to fork and add the Windows and Mac OS examples.
C99 understands variable-length arrays. They look something like this:
int d1, d2, d3, d4;
// runtime-assign those variables
int vla[d1][d2][d3][d3];
Now the question is, how to properly cast a pointer to this type when passing it to a function that accepts such a type in a way that makes the compiler happy? The syntax is somewhat unusual:
void func(int d1, int d2, int d3, int d4, int vla[d1][d2][d3][d4]){}
// ...
int * x = malloc();
func(d1, d2, d3, d4, (int (*)[(int)(d2)][(int)(d3)][(int)(d4)])x);
Tested with gcc 4.6.1 and the –std=c99 compiler option. I could not find information about this anywhere on the web so I hope this will help others who wonder how it should be done.
Over the years computers grew in numbers and a logical step in their evolution was to connect them together to allow their users to share things. Little networks grew into huge networks and some computers gained more power than the rest: they called themselves “servers”. Today millions of people are connected online at the mercy of middleman who control the servers of the world.
This is not an introduction to an dystopian fantasy world but an excerpt from a promotion video for Opera Unite, a framework that allows users to host information from their home computer. It was a bold attempt to change the centralized architecture of the Internet. A number of smartpeople have been pondering this idea even before Opera’s experiment failed miserably.
And the concept of a decentralized web is gaining traction: more and more people realize something has to change. The cause for this trend is obvious: the number of data security and privacy disasters that were made public has spiked in recent times . In April ’11 for example an update to the security terms of service of the widely used Dropbox tool revealed that contrary to previous claims, Dropbox Inc. has full access to user data.
An analysis of the changes to the Facebook privacy policy over time paints a gloomy picture of how the world’s largest social network changed “from a private communication space to a platform that shares user information with advertising and business partners while limiting the users’ options to control their own information”.
With more and more of our personal data moving to centralized servers or “cloud services” – a term that should be used as an euphemism – we’re no longer in control. But there is hope in sight: there are dozens of projects out there that try to stop the trend of centralization and data consolidation.
Decentralized Applications
The most popular of the lot is probably Diaspora. The project got a lot of attention in April 2010 when they managed to raise about $200.000 from almost 6500 supporters. The software looks and feels very much like Facebook or Google+. The innovation is that users are allowed and even encouraged to set up their own Diaspora node. This essentially means allowing users to set up their own Facebook server at home (or wherever they want). The Diaspora nodes are able to interact with each other to form one distributed social network. Furthermore, instead of users having to log in to one central server, they may choose one of many servers administered by different entities. In the end they can decide whom to trust with their data and there is no one entity that has access to all the data.
A social network project that is also worth mentioning follows the same principle. Its name is Buddycloud. The main difference between Buddycloud and Diaspora can be found in their implementation details: Buddycloud builds upon XMPP (Extensible Messaging and Presence Protocol), a more than 10 year old and often implemented specification for “near-real-time, extensible instant messaging, presence information, and contact list maintenance”. There are many unknowns in this area so building on such proven protocols instead of defining new standards might proof to be an advantage. But there are many more social networking projects out there. Wikipedia has a nice list.
The Unhosted project implements another concept. Instead of providing a specific decentralized service it aims to be a meta-service. And after talking to Michiel de Jong I have the impression his plan is even more crucial. He aims to create something fundamental, a protocol, an architecture, a new way of writing web applications. The idea is the following: the traditional architecture of a hosted website provides both processing and storage. An unhosted website only hosts the application, not the data. Unhosted wants to separate the application from the data. By storing the data in another location and combining both application and data only in the browser, the application provider can never access the data. An ingenious and very ambitious idea. I hope they succeed!
Decentralized Storage
A project that aims to replace Dropbox is ownCloud, an open personal cloud which runs on your personal server. It enables accessing your data from all of your devices. Sharing with other people is also possible. It supports automatic backups, versioning and encryption.
The Locker Project has similar goals. They allow self-hosting (installing their software on your own server) and offer a hosted service similar to what Dropbox provides. The service pulls in and archives all kinds of data that the user has permission to access and stores this data into the user’s personal Locker: Tweets, photos, videos, click-streams, check-ins, data from real-world sensors like heart monitors, health records and financial records like transaction histories (source).
A third project worth mentioning is sparkleshare. It is similar to the other projects in this category but allows pluggable backends. That means you can choose to use for example Github as backend for your data or of course your personal server. Awesome!
Freedom to the Networks
Projects such as netless carry the idea even further because after the data is liberated, the connection itself is a soft spot. Network connections should be liberated from corporate and government control by circumventing the big centralized data hubs and instead installing a decentralized wireless mesh network where everyone can participate and communicate.
The adventurous netless project plans to use the city transportation grid as its data backbone. Nodes of the network are attached to city vehicles – trams, buses, taxis and possibly – pedestrians. Information exchange between the nodes happens only when the carriers pass by each other in the city traffic. Digital data switches its routes just the same way you’d switch from tram number 2 to bus number 5. Very inspiring.
Another idea is to utilize networks of mobile phones to create a mesh network. The serval project is working on this. And they have a prototype for the Android platform ready.
The German Freifunk community pursues a similar goal. It is a non-commercial open initiative to support free radio networks in the German region. It is part of the international movement for free and wireless radio networks (source).
A purely software based project is Tor. It is free software and an open network that helps its users to defend against a form of network surveillance that threatens personal freedom and privacy as well as confidential business activities and relationships.
Peer to Peer Currency
One integral thing this article did not talk about yet is money. Bitcoin, a peer to peer currency, might be the missing puzzle piece. The Bitcoin system has no central authority that issues new money or tracks transactions – it is managed collectively by the network.
A major problem of digital currency has been preventing double-spending. Digital money can be copied multiple times so a mechanism is necessary to forbid spending money twice. Bitcoin refrains from having actual digital coins. The system is merely one large transaction log that tracks what money was transferred where.
Each participant has a pair of public and private keys to sign transactions and to allow others to verify transactions. The transactions are entered into a global ever running log that is signed in regular intervals. The signing of the log is designed to require extensive computation time. The entire network of participating users is required to sign the log.
This protects the entire system from false signatures and from anyone tempering with the log and modifying past transactions. An attacker would have to have more computational power at his disposal than the entire Bitcoin network to forge transactions.
Users that give their computing time to the network are rewarded with Bitcoins for their troubles. This is also how the money is generated in the first place. In addition, participants that transfer money are free to include a transaction fee in their order. This extra money is given to the particular user signing the transaction.
A considerable number of sites have emerged that accept Bitcoins in exchange for services or goods. You can buy for example socks online or even pay for your lunch at a burger restaurant in Berlin.
Conclusion
In closing, I find it encouraging, that so many people feel that things have to change and are developing ideas and projects to make it happen. We will see many exciting things in the future and despite the overwhelming might of well-established products, I am hopeful.
I just returned from a world of distorted day-night-rhythm, caffeine, camping, data toilets, colorful lights and most importantly ingenious people and projects. There were some great talks and many great hackerspaces from Germany and around the world were attending.
Every attendee at the conference received a r0cket badge when arriving at the campground. It’s a “full featured microcontroller development board” including a 32-bit ARM Cortex-M3 LPC1343 microcontroller, a 96×68 monochrome LCD and 2.4GHz transceiver for mesh networking.
HAM-radio enthusiasts from Metalab were working on Moonbounce: radio communication over a distance of at least 2 light-seconds using the Moon as reflector.
A couple of microcopter and drone projects presented their work. There was for example the NG-UAVP project. They released a couple of great areal videos. A project I did not know but I find particularly fascinating is the Paparazzi project. It is an “exceptionally powerful and versatile autopilot system for fixedwing aircrafts as well as multicopters”. This is a project that is for example used by Scientists from the Finnish Meteorological Institute to measure temperature, humidity, pressure, wind direction and speed in altitudes up to 1000m at Antarctica. Very impressive!
For me personally, meeting a number of interesting people that are part of the decentralized web movement was really great. Because of some truly enlightening conversation with people from the FreedomBox Foundation, Michiel de Jong from unhosted.org and buddycloud developers I started thinking about the whole topic again especially about host-proof applications and what a host-proof social network could look like.
How to get the version of the Nvidia kernel module on Linux? I’m posting this here because I’m sure I will forget this again. This is very relevant when evaluating that the proper driver is installed for CUDA use.
I added a Talks-page to this blog. I plan to list and publish interesting talks I gave at various occasions. Currently the page lists two talks: a GPGPU seminar I gave a year ago at my old university and just recently I had the honor of speaking at BoostCon about the project I worked on last year: a library for the Cell processor.
“Stallman was right” is one of the important messages Eben Moglen conveys in his recenttalks about Freedom and the Cloud. He’s a convincing speaker, his arguments are striking and the cause might very well be one of the most important challenges the Internet faces right now.
He speaks about privacy: the freedom to choose who to share what information with. He speaks about freedom of speech: the liberty to speak and communicate freely without censorship. He speaks about how we give up those freedoms, often without noticing or worse, without caring. By signing up to facebook. By using Gmail.
It’s insane if you think about it. We communicate with our friends, send them private messages, through a database in Northern California. We store our personal information including images in that same database. And while we put more and more information, more and more of our lives in that database, its owners are busy thinking about ways of how to make money with our data. By now I’m sure they have come to at least one conclusion: to make money they will share our data with entities we never intended to share it with.
It gets worse, and Eben Moglen elaborates this very well in his keynote speech at Fosdem 2011. All our data is routed through and even stored in a company’s database. We can choose to trust that particular company to not do anything bad with our data. But we can never be sure that the company will act in our interest if it is offered incentives (“We won’t shut you down if you comply”) to share certain data with certain government agencies. Since our data is stored in a centralized manner, agencies the likes of NSA would have a field day.
So indeed, Stallman was right when he called cloud computing a trap. He advises us “to stay local and stick with our own computers”.
Eben Moglen sees the urgency of these problems so he is taking action: informing the public with persuasive talks and gathering smart, ingenious and influential people to find solutions under the newly founded FreedomBox Foundation. The ingredients to the solution, in accordance to Stallman’s suggestion have been identified:
cheap, compact plug computers that can be used as personal servers
a free (as in freedom) software stack that is designed to respect and preserve the user’s privacy
mesh networking technology to keep the network alive if centralized internet connections fail
The idea is simple: replace all cloud services (social network, e-mail, photo storage etc) with distributed systems. The FreedomBox project aims to provide everyone with a compact, cheap, low-power plug computer. Such a device will come preloaded with free software that “knows how to securely contact your friends and business associates, is able to store and securely backup your personal data and generally maintaining your presence in the various networks you have come to rely on for communicating with people in society”.
There are a number of other projects out there that are worth mentioning here. A very interesting assessment of the current state of the social web and existing standards is the W3C Social Web Incubator Group report. The Diaspora project develops distributed and secure social networking software and is worth keeping an eye on. The FreedomBox community maintains a comprehensive list of existing projects.
I expect the foundation to develop a software package that provides stable system software and that encompasses a number of existing projects that allow users to move from cloud services to their own server. I will help were I can and so should you!
