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What exactly is "Distributed Computing"?

To put it simply: Imagine: You are a scientist and got an idea how to produce a new vaccine. There are usually at least two possibilities:

1. You go to a laboratory and conduct research until you find your solution after several years.

2. You develop a formula a computer can use to simulate so you do not need to go to the laboratory in person. Therefore you rent for several month a mainframe computer having a lot computational power at your disposal. That would cost you about 100,000 Euro.

Both scenarios are not a viable praxis. In case 1 you need to much time. In case 2 you spend to much money. But there is an alternative: You do not rent a mainframe, but use the computational power of single computers in for instance various households and schools. There is a lot of computational power unused, when people work at their PC's, which can be used to conduct scientific research. The scientist has no costs and the user of that particular PC has no disadvantage.

How is Distributed Computing affecting my daily work? Am I not to switch my Computer off?

That particular question is being asked quite frequently. The simple answer is: For any user there is no change whatsoever. The computer may be used just in the way it was prior to the scientific use. If the software resp. the operating system is configured correctly, one doesn't even notice that in the background "invisible helpers" are at work. If those programs asked the user in irregular intervals to intervene, nobody would install such a program, no matter what general benefit may come from using that program. An important characteristic of so called "distributed computing programs" is not to annoy or to create additional work for the user, as to what he/she had before. This excludes of course the software updates, which are necessary from time to time. Every once in a while results are saved automatically; if the PC is turned off and on agin, the ditrbuted program continues the work from the last checkpoint.

What projects are available for me? Or do I not have the ability to choose between different projects?

Anyone can decide him- or herself which project to support. Some are intrested in cancer research, others think it is more important to predict climate change and others again are just intrested in how many websites there are on the internet. The list containing all projects is long and contains various topics, and what is more: there are monthly new projects from many fields of research. An overview is available here.

Has each project its own program or do I just need one program for all projects available?

This is different from project to project. Some for instance Folding@home have their own software, which can only be used for this project and this project only. There are programs as e.g. BOINC, which allows the user to manage multiple projects simultaneously. One can inform him- or herself which projects are compatible with the BOINC-software. Many new projects are supported by BOINC.

Is it possible to join without permanent connection to the internet?

Even without a permanent internet connection ditributed computing is possible. However, one should regard the following points:

Long running or many work units

In general, for computer without connection to the internet all projects are suitable, which either have very long (several weeks or more) running work units or permit to download a great many WU's without them passing their deadline. Furthermore, it must be possible to transfer those WU's using LAN or USB, resp. floppy-disks to that PC. Projects providing those abilities are among others

Random work units

Additonally, there are projects, which calculate their data randomly (meaning they do not download WU's). Those are, among others

Unfortunately concluded are

Multiple installations

If a client can only download a few WU's, the problem can be bypassed by a little trick: Some clients can be installed in multiple instacnes on one and the same PC. So the amount of WU's can be increased. The different instanced can be run simultaneously or one after another. If all work units are successfully concluded, one can download new ones for all instances.

Use of BOINC on PC's which are always offline

  1. Install BOINC completely on a USB-stick
  2. Register project, set a huge buffer, update project manually
  3. End BOINC
  4. Use that stick with the computer, which is always offline and start BOINC

After those work units are done:

  1. End BOINC and take the stick to a computer, which is connected to the internet
  2. Restart BOINC at that PC, update project, so new WU's can be downloaded and concluded ones uploaded

My notebook is getting too loud when calculating permanently

Fans of notebook CPUs are known to be quite loud when running under full load. There are 3 possibilities to fix that problem:

  1. Limit CPU usage of the client (e.g. possible when using BOINC). Unfortunately this is not possible with all projects.
  2. Limit CPU usage by another program,for instance a BOINC-AddOn or for Windows in general ThreadMaster. Experiments with different settings prooved to be well working with threshold values of about 40 to 50 percent. So, there is a viable solution between performance and noise level.
  3. Clock down the CPU. By that means the generation of heat is being significantly deminshed, so the fan can speed down. What is more, one does save energy. There are again 3 possibilities to do that:
    1. Clock down the CPU in the BIOS (and if necessary decrease voltage). Clean but unflexible.
    2. Clock down CPU using the operating system. Again clean, but not a viable solution for all OS's/CPUs.
    3. Clock down the CPU using an installed program (e.g. SpeedSwitchXP for Windows XP). Very flexible, but you need additonal software.

Could such a program be a security risk for my computer?

Distributed computing clients are normal computer programs. They act just like any other program concerning security. They are neither more nor less secure/unsecure than any other program. Eventually, they conduct complex calculations (like one could do using EXCEL or OpenOffice) and share their solutions with another computer. Additional information is available here (German, we are currently working on a translation).

How do I profit of participation in a project?

You help to significantly advance scientific research, which would last considerably longer without your provided computational power. Even though each computer is just a "small light" by itself; various PC's are powerful! And perhaps is it YOUR computer that finds the missing link for a cure of cancer, AIDS or Alzheimer's disease.

Some projects even offer rewards or the chance of winnigs or they designate the owners of PC's, which came up with scientific solutions, in their publications.

Answers in how far a participiant profits and why are provided by FreeStyle-Episode-1 of BOINCcast. Unfortunately, this Podcast is available in German language, only.

That will cost me a lot of energy, will it not?

Jürgen Hochwald has done a measurement for his computers using different projects and got the following values (for his complete system):

Athlon 650

Athlon Thunderbird 1200

So, depending on your processor and the choosen project, energy consumption will be increased by ca. 20 to 40 Watt. That equals 0.5 to 1 kWh additional power consumption or a total consumption of 2 to 3 kWh.

With an assumed electricity price of 15ct/kWh you will pay for a PC running 24/7 daily around 0.30 to 0.50 EUR. Compare: As a smoker you would get about 2-3 cigarettes daily, meaning a PC running 24/7 is the cheaper hobby. Additionally, you should activate the power-management and thereby turn off monitor and HDD's after some time (switch off monitor completely over night).

Isn't it unfair, when many people help discover vaccines against some diseases and afterwards the pharmaceutical industry makes money with that?

Whether to compute for commercial projects (those are marked in our projectlists as such) or not, is repeatedly subject of debates. In the end each person has to decide that for him- or herself.

As pro arguments there are:

  • The discovery of a potential vaccine is just one small step in the process of finding a cure for a disease. The most costly part (it sometimes can go into the 100-millions) are the clinical tests for licensing. Those companies may get some help by the community but the main financial expenses are still with the companies.
  • Most patients pretty much do not care, if companies earn money by the means of that medicine, as long as there is one at all.
  • Even with DC, vaccines will never be available at no-cost, since the producing company has still to pay for ressources, machines, labour force, etc.

As contra arguments there are:

  • Many people (especially in poorer regions) cannot afford proper medication - vaccines found are thereby distributed in the western countries for the most part of it.

It should be noted, that the majority of all projects is not commercial. Exceptions are clearly marked as such.

Is there an overview of the arguments pro and contra Distributed Computing?

Yes, you may find it here (untranslated, yet).

May I do more that just install a Client?

Yes, indeed! You may:

  • become an active user of our Forum and/or Chat.
  • join (untranslated, yet) our association or donate(untranslated, yet) some money or hardware. Since we are officially a charity organisation, you may even be able to offset that amount against tax. See your country's financial law for that possibility, please.
  • join our teams in the various projects.
  • refer in other forums or tell your friends about Distributed Comuting or our page (please don't SPAM, as it would be counterproductive!).
  • create a profile on the BOINC project pages, refering to our team.

If you already have some exierience with Distributed Computing, you may as well:

  • help others in the forums of the various projects.
  • enlist for support at BOINC.
  • help us with further enlargement and the update of our Wiki pages.

If you have your own apperance on the Net, e.g. a blog or a homepage, we would appreciate it, if you linked to our page. You may find banners here.

I am already computing for another team. May I do something here, nonetheless?

Certainly! Although Rechenkraft.net e.V. has its own DC-team, the association understands itself as independent organisation. Members of other teams are always welcome in our association - we really do appreciate their contributions in the Wiki or our Forum.

What means...

Some abbreviations in connection with Distributed Computing can be found in the glossary (untranslated, yet).