Archive for November, 2009

Build a Mechanical Computer

Monday, November 30th, 2009

Build Your Own Digicomp Mechanical Computer! tells about a plastic mechanical computer from the 1960s. It offered three bits of tabletop computing, back in an age where corded telephones were considered high-tech. According the article Digicomp started a bunch of kids on a career in computers. Now a member of “Friends of Digicomp” Yahoo Group has introduced an updated version this cool little looking machine. This kind gadgets have potential to give combination of hands-on and minds-on fun.

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Industrial Ethernet Technologies

Friday, November 27th, 2009

Industrial Ethernet Technologies: Overview is a presentation intended to give an overview over the most important Industrial Ethernet technologies. It is good reading for anyone working with Ethernet and/or automation applications.

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Default Password List

Wednesday, November 25th, 2009

Default Password List has saved the day several times when working with different network equipment. When the instructions are missing or the information on default passwords is very well hidden within the documentation, the Default Password List will give you the password information you quickly.

Failed Office Pranks

Sunday, November 22nd, 2009

Practical jokes do not always go well. Sometimes the most innocent jokes have the most tragic consequences. 8 Innocent Office Pranks That Went Horribly Wrong web page shows you eight videos of office pranks that did not work as expected.

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Making of Space Chair Ad

Friday, November 20th, 2009

John Huntington’s Entertainment Technology Blog has an interesting posting Toshiba’s Very Cool “Space Chair”Ad. It consists mainly of two videos. The first video shows the cool Toshiba TV ad. The second video is the “Making of” video. It tells how the ad was made using several high definition cameras rigged to a big weather balloon that lifts the whole system to the sky.

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Academia vs. Business

Thursday, November 19th, 2009

xkcd webcomic has today a funny comic about difference between academia research and business. Check out that Academia vs. Business strip yourself on the comic web page (the comic strip picture is too big to fit to the layout of this blog so I could not add it nicely here).

Passive Ethernet Tap

Monday, November 16th, 2009

Construction and Use of a Passive Ethernet Tap article provides straightforward instructions on how to construct and use a passive Ethernet tap. It allows you to monitor Ethernet traffic on with any hub or switch and any operating system. A passive Ethernet tap is useful when installing an intrusion detection system (IDS) sensor or when snooping Ethernet traffic. I have used this passive Ethernet Tap for successfully monitoring 10 Mbit/s and 100 Mbit/s Ethernet traffic.

This circuit is a widely used hack. It is a hack in a sense that it is not technically up to the specifications an Ethernet device should need, but it is simple and works pretty well in most cases. The simple construction method used in this circuit creates impedance mismatches to the communications line, which are not good for the communications. But because Ethernet is pretty robust technology this “not so good” system works well enough when we are not using the Ethernet up to it’s extreme limits. The Ethernet communications is designed to work up to 100 meters cable length when properly wired. When you use considerably shorter cables, there is more room for different kind of imperfections on the communications line, for example imperfections like this passive tap. When I have kept the main communications line cables less than 10 meters in length and the tap cables 2-3 meters long everything has worked well.

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The Creepiest Thing You Can Do To a Building

Wednesday, November 11th, 2009

The Creepiest Thing You Can Do To a Building web page shows you very many pictures how adding a little bit of graffiti or other props to building air ducts can make them look very creepy. This page will give very good ideas for practical jokes.

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Fading Usenet Newsgroups

Monday, November 9th, 2009

Usenet Newsgroups have been great over the past almost twenty years for me. I am finding less and less good posting and always more and more spamming. I fear that we are witnessing the death-rattle of the terminally. The problem is not Usenet newsgroups. Thousands of them are thriving quite nicely today just as they have for decades. The problem is that people do not seem to use them as much as earlier and more spam coming to them.

I still find all the web-based forums to be too primitive. Too often the problems are both user interface and the content (too many forums and too few really good and active). No web-based forum holds a candle to real Usenet. If you only know Usenet through a web-based interface like Google Groups, then you don’t really know Usenet. All web-based forums are dramatically inferior to Usenet.

Likely many of us also use web-based forums for certain specialty topics, particularly forums that are chartered for the discussion of certain hardware and or software, etc. But the Usenet newsgroups continue to be orders of magnitude faster and more efficient than any web-based forum I have seen in 20 years.

Web-based forums are generally HORRID. I avoid them unless absolutely necessary. If you have never used a real Usenet newsreader client and a proper Usenet NNTP server, then you are in no position to judge what is happening to this or any other Usenet newsgroup.

Computers at the International Space Station

Wednesday, November 4th, 2009

The International Space Station (ISS) isn’t just an orbiting laboratory, spaceship testing-ground and multinational geek-fest — it’s also the world’s highest (250 miles) and fastest (17,500mph) computer network. Tracking and Data Relay Satellites (TDRS) allow constant radio communications in the S- and Ku-band, while UHF signals are used to talk with the Space Shuttle and crew members on spacewalks. There’s also a single IP phone for cheap interstellar calls and ‘limited’ webcam video-conferencing abilities. There is significantly large network on board the Station, comprising 68 IBM ThinkPad A31 laptops and 32 Lenovo ThinkPad T61p devices. Space Station IT: High technology article tells about the IT technology used on board. Interview: The Space Station’s IT guys interviews Tyson Tucker and Joey Crawford, the NASA flight controllers responsible for maintaining uptime in mankind’s first permanent space colony. I saw those interesting articles first mentioned at Slashdot.

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