[Rob]

Overview: What is Distributed Computing

Most desktop and laptop computers are underused when they are switched on. Many of us now have powerful processors and lots of memory. Emailing, word processing, or just checking on Cable Forum barely makes the modern CPU break a sweat. When you go off to answer the phone, have a brew, or stop playing games, your computer just sits there using electricity, for nothing. If you don't believe this (assuming you have windows), do the three fingered salute, click the processes tab and you'll see the majority of processor power is devoted to "System Idle Process".

Distributed Computing projects take advantage of this underused computer power. All are scientific research projects, some medical, some trying to find cures for illnesses or new drugs, some looking for signs of Extra Terrestrial life. The combined power of the spare capacity available from the millions of computers vastly exceeds the most powerful supercomputers. Without Distributed computing, most of the projects being run would take years to achieve results.

How does it Work?

Each Distributed Computing user creates an account with the project(s) of their choice. The project will provide free client software, that enables your PC to receive the work, do it's thing on it, and send the completed results back.

Each project breaks their massive task into small segments or Work Units (WUs). These WUs are processed (crunched) by your computer with the results being returned via the Internet for analysis and checking (validation). Most projects send the same WU to three or perhaps more computers, and comparing the returned results for validity. There is often a time limit for the crunching of WUs and returning the results, to ensure there are not lots of incomplete WUs kicking around.

What’s the Catch?

You don't earn any reward, for the donation of your computer's resources, and burning your electricity! You are a volunteer.

The only acknowledgement you will get, is a warm feeling inside (perhaps caused by the heat output from your computer). There may be a down-loadable certificate when you have done certain amounts of a project. Most projects create credits per WU completed. These are displayed in league tables amongst fellow crunchers on that project. Be warned, these leagues can become addictive. Many enthusiasts will run more than one computer on one account so as to boost their standings in teams. We know of some people who will run many computers (often referred to as a farm) for nothing else than climbing that league table. However, you should only run DC on computers that you own. Offices often take a dim view of borging (assimilation - get it) of computers on to your account, when they aren't your property.

Distributed Computing Projects are at low priority on your computer. Simply put most applications run at normal priority, thus DC stuff will only operate on anything unused and the CPU is released whenever it's needs for other stuff. DC restarts again automatically when you stop needing the CPU. It's a hidden process. There will be some memory use, so you perhaps want some spare capacity there, although most modern PCs are well specified in that department. Very few users would notice DC is running. However gamers, or those making very intensive use of their computer’s power, may wish to suspend DC projects whilst in the middle of their session.

There is no evidence to say your computer will be harmed. Your CPU computer will be working hard, but it’s designed for this. The biggest issues are of temperature. As the computer is running intensively, the processor memory and other components might get quite warm. Keeping your computer well ventilated is important. You may well notice some increased noise from coolant fans spinning faster.

Inevitably you will wish to trust the project you are running that it’s software is safe, i.e. free from viruses and the like. But these days we all have firewalls and anti virus software?

The most obvious catch is your electricity bill, and the time you spend checking on your latest addiction. If the computer would be on anyway for your normal use, you aren’t adding significantly to your power consumption. It's only when you start leaving your PC on all the time, when your wouldn't have done so before, that your bill's increase. However there are many who argue that switching a PC on and off degrades it (not that this is proved) as the temperature changes might affect the electronics, so leaving it running all the time is a good thing, right?

What Do I Need?

The faster your computer the greater will be your potential contribution. A reasonable memory capacity is a must, and most projects will use some Hard disk space, some projects potentially a lot. Virtually all machines built within the last three or four years will be useful. Pentium III (or equivalent) PCs of 1GHz and above will do things, but very slowly. It's probably only worth using these if the PC was on for other reasons. The Pentium 4 (or equivalent) makes a great cruncher. The latest hyper-threaded or dual core CPUs enable you to crunch two WUs simultaneously. Some projects are even experimenting with harnessing the power of the latest graphics cards! Many of the DC project software will benchmark your PC and then only download WUs that the machine is capable of crunching.

Most projects, were developed for Windows software (virtually all support XP, and most 98 and 2000 or ME), simply because of the user base. Linux and Mac computers are also well supported by some but not all projects.

You need Internet access. Broadband is recommended simply because it's there when the PC needs to upload results and download a new WU, and some files might be large, or reasonably frequent. Dial up will work.

A quick word about overclocking, the process of making your PC run faster than the manufacturer's rating. This can be fine, and if it works means your WU will complete quicker, but watch those temperatures! However do be sure your system is perfectly stable. Poorly clocked machines can return bad results which benefits nobody.

Most projects use screen-saver (GUI) based client software by default. These screen-savers may be graphically interesting but, the graphics require CPU power. Addicts will scorn the GUI in favour of a command line client (CLI) that avoids the graphics altogether. Some of CLIs can be installed as a service enabling totally automated processing that you forget about, rather like your anti virus software.

You will setup a user account with each project. You may need to register with a valid email address. Download the client software from the project, install it to the computer, and enter your user account details, the WU processing should then be automated.

As a rule, while there are any DC projects to choose from, you should only run one project at a time. Dual core CPUS can do two separate projects, but that may take some setting up. However, the BOINC platform does allow CPU time to be shared, between many of the DC projects that use it

The projects and the Cable Forum Teams

Cable Forum Members do participate in DC projects!

You can just donate your spare computing capacity to a project. There is no obligation to be part of a team, but motivation counts. Teams provide a friendly competitive spirit amongst participants, a common cause to beat other teams, but most importantly a sense of real belonging. This encourages participants to crunch more. It can all become quite addictive - not to mention expensive. Active teams also provide a base where experiences and problems can be shared. Projects have recognised the ability of teams to enhance the crunching spirit.