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Debunking the Nikola Tesla myths by way of defending Thomas Edison

Guru 42 Blog -

When I created the GeekHistory website my main goal was to draw attention to the many scientists and inventors that I call the forgotten geeks. It was not my plan to spend a lot of time defending Thomas Edison, after all he does get mentioned often.

As I revved up my writing for the GeekHistory over the last few years I have become active in social media looking for common questions about famous inventors and inventions. In search of information on all the "who invented it" myths of technology history I found a great deal of misinformation giving credit to Nikola Tesla for a variety of inventions. I find myself often defending Thomas Edison because of often over the top claims of everything that Nikola Tesla allegedly invented.

Nikola Tesla has a cult following that gives him credit for inventing just about everything. There are people who object to the phrase "the Cult of Tesla," but the Tesla fanatics are a prime example of a cult. Tesla fanatics have an "us against them" mentality with stories full of conspiracy theories of how the government took all of Tesla's files when he died. When it comes to any attempts to have a rational conversation, they deny any facts that might contradict the group's beliefs. Having a meaningful conversation with Tesla fanatics can be frustrating because there is a complete avoidance of critical thinking.

Studying the claims of Tesla fans, searching for the truth, has made me even more passionate about my original goals of drawing attention to the forgotten geeks who deserve to be remembered. One of the many claims of Tesla fans is that Tesla invented radio. In the process of digging deeper to learn more I came to appreciate the work of Fessenden. Who is the inventor who started his career working for Thomas Edison, later worked with George Westinghouse, and has a legitimate claim to be called the father of radio? The answer to that question is not Nikola Tesla, it is Reginald Fessenden.

From his work for George Westinghouse and the University of Pittsburgh, to the story of Fessenden's 1905 Christmas broadcast to ships at sea, he is indeed a forgotten geek that deserves to be remembered. Check out the complete story of Reginald Fessenden Canadian inventor of radio and wireless telephone

For all his quirks, I do appreciate the contributions of Thomas Edison. Including the mountains of material I have read, I have made two visits to the Henry Ford Museum of American Innovation and Greenfield Village near Dearborn, Michigan in recent years to study the accomplishments of Edison and other geeks. Just as I note the exaggerations of the Tesla fans, you can say that the claim that science becomes religion goes both ways. Henry Ford idolized Thomas Edison, you can clearly see that in the Henry Ford museum complex. The complete Menlo Park lab from New Jersey was transported to Michigan and rebuilt there. Henry Ford had a dedication ceremony for the reconstructed lab that Edison attended when it opened.

There are many forgotten geeks who made incredibly important contributions in bringing electricity to our homes. Nikola Tesla did not invent AC power generation. Tesla's sole contribution was his version of the polyphase AC motor. Significant, but it was theoretically described by other others before him, as were many of the other inventions and discoveries often credited to Tesla.

As we created the section on the history of electricity we broke it down into four sections starting with a list of scientists and inventors that contributed to our modern understanding of electricity.

Our next page looks at the European inventors before Edison and Tesla who contributed to the development of electricity and AC power distribution

It bothers me that so many internet sites talk about the War of Currents as the great battle between Edison and Tesla. Edison eventually lost control of Edison Electric as it merged with another company to become General Electric. Nikola Tesla was not a member of team Westinghouse when the War of Currents started between George Westinghouse and Thomas Edison. Follow this link to learn about the many Westinghouse Electric engineers responsible for electricity and AC power in our homes

Edison does deserve credit for many inventions in a wide variety of areas, and in defending Edison, I have come up with a fair amount of material for the GeekHistory websites. Edison might have been too stubborn to back down on DC power generation as the way to produce electricity, but he does deserve to be respected for launching the modern electric utility industry with the creation of the Pearl Street station in lower Manhattan in 1882 When the War of Currents ended around 1893, Thomas Edison was no longer in control of Edison Electric. But the Edison team (which became part of the General Electric Company) lived on in many ways.

Reginald Fessenden worked several years for Edison, before joining forces with Westinghouse. In the biography "Fessenden – Builder of Tomorrow" - by Helen Fessenden (his wife), you will find remarks by Reginald Fessenden defending the legacy Thomas Edison.

"The question has often been put to me 'Is Edison really a good inventor? Are not his inventions really due to his assistants?' Having worked with him for a number of years and having made a rather special study of the science of invention and of inventors, my own conclusion is that all of the inventions which go by his name were made by him personally, and that there is only one figure in history which stands in the same rank with him as an inventor, i.e. Archimedes."

Edison had the reputation of a hard driving businessman, but he was also passionate about creating an invention factory. Edison paid workers to conduct numerous tedious experiments so he did not have to do the boring manual tasks himself. I think that is pretty genius.

Some of the Tesla fans point to crazy things that Edison did to discredit him as an inventor. Don't get me wrong, Thomas Edison was no saint, he was a lunatic at times, but to discredit Edison as a means to glorify Tesla is more than a little humorous. Nikola Tesla cornered the market on craziness during his lifetime.


A few more links to learn more:

Nikola Tesla versus Thomas Edison and the search for the truth

George Westinghouse used Tesla power to defeat Edison in Currents War

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Computer networking packet switching explained in simple terms

ComputerGuru -

Throughout the standard for Internet Protocol you will see the description of packet switching, "fragment and reassemble internet datagrams when necessary for transmission through small packet networks." A message is divided into smaller parts know as packets before they are sent. Each packet is transmitted individually and can even follow different routes to its destination. Once all the packets forming a message arrive at the destination, they are recompiled into the original message.

Internet data, whether in the form of a Web page, a downloaded file or an e-mail message, travels over a system known as a packet-switching network. Each of these packages gets a wrapper that includes information on the sender's address, the receiver's address, the package's place in the entire message, and how the receiving computer can be sure that the package arrived intact.

There are two huge advantages to the packet switching. The network can balance the load across various pieces of equipment on a millisecond-by-millisecond basis. If there is a problem with one piece of equipment in the network while a message is being transferred, packets can be routed around the problem, ensuring the delivery of the entire message.

Packet switching explained in simple terms

In teaching the concept of packet switching in the classroom, I would take a piece of paper with a message written on it, and from the front of the classroom, ask the person in the front seat simply to turn around and pass the paper to the person behind him, and in turn continue the process until the paper made it to the person in the back row.

In the next phase of the illustration, I would take the same piece of paper that had the message written on it, and tear it into four pieces. On each individual piece of paper I would address it as if sending a letter through the postal service, by writing my name as the sender, and also the name of the person in the back of the room as the recipient. I would also label each individual piece of paper as one of four, two of four, three of four, and four of four.

This time I would take the four individual pieces of paper and walk across the front row, and as I handed one piece of paper to four different students, I would explain to them who was to receive the paper, and asked them to pass it to the person marked as the recipient by using the people behind them. When all four pieces of paper arrived at the destination, I would ask the recipient to read the label I had put on each piece of paper, and confirm they had received the entire message.

My original passing of the paper represented Circuit switching, the telecommunications technology which used circuits to create the virtual path, a dedicated channel between two points, and then delivered the entire message.

My second passing of the "packets" or scraps of paper illustrated packet switching, and each individual in the room acted as a router. The key difference between the two methods was the additional routes that the pieces of the message took. A very primitive, but effective demonstration of packet switching and the way in which a message would be transmitted across the internet.

Once the concept of packet switching was developed the next stage in the evolution was to create a language that would be understood by all computer systems. This new standard set of rules would enable different types of computers, with different hardware and software platforms, to communicate in spite of their differences.

Geek History: In the 1960s Paul Baran developed packet switching
 

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Wondering about the dark web and the forbidden fruit of the internet

Guru 42 Blog -

The phrase forbidden fruit typically refers to engaging in an act of pleasure that is considered illegal or immoral. That fits the mold of many questions I am often asked, such as what are some of the illegal or immoral websites you can find on the mysterious and mythical part of the internet known as the dark web.  The mysterious dark web, sometimes called the dark net, is the fuel for spy movies. it helped to create WikiLeaks run by the super spy Julian Assange and it allows cyber snitches like Edward Snowden share secret information. People are axious to know how to find what is hinding beneath the surface in the dark web.

According to remarks made by Roger Dingledine at a recently Philly tech conference, the overall perception of the dark web is more mythical than factual.  Roger Dingledine is an MIT-trained American computer scientist known for having co-founded the Tor Project, aka "the dark web."  Dingledine spoke at the Philly Tech Week 2017 putting some of the myths and legends of "the dark web" into perspective.

The worldwide network known as “the dark web” uses specially configured servers designed to work with custom configured web browsers with the purpose of hiding your identity. You will see the term Tor servers and web browsers to describe this private network. Tor originally stood for "The Onion Router."  The Tor Project, Inc is a Massachusetts-based research-education nonprofit organization founded by computer scientists Roger Dingledine, Nick Mathewson and five others. The Tor Project is primarily responsible for maintaining software for the Tor anonymity network.

If you are looking for all that forbidden fruit hiding beneath the surface, according to Dingledine no more than one to three percent of the Tor Network’s traffic comes from “hidden services” or “onion services”, services that use the public internet but require special software to access. Dingledine claimed that onion services basically do not exist. He added that it’s a nonsense that there are “99 other internets” users can’t access.

One popular way often used to describe the deep web and dark net is to use a graphic of an iceberg. Dingledine advises his audience not to pay attention when someone uses the iceberg metaphor, and criticized the news providers who use the “iceberg metaphor” for describing the darknet and the deep web.  According to Dingledine, just about any use of the “dark web” phrase is really just a marketing ploy by cybersecurity firms and other opportunists.  So the forbidden fruit you were hoping to find really is just a myth after all.

Learn more:

People are fascinated about what you can find on the dark web, but have no idea what it all means. Learn more from Guru42 in this article where I go over the basic definitions with links to learn more: Buzzwords from the world wide web to deep web and dark net

Referencing Roger Dingledine at Philly Tech Week 2017 here are some links about that event:

Stop Paying Attention When Someone Uses The Iceberg Metaphor For The Dark Web

Stop talking about the dark web: Tor Project cofounder Roger Dingledine

 

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Weird science behind conspiracy theories and urban legends

The World of Questy -

When I was in high school a friend of mine was really into the Erich von Daniken books, some of you might remember the best-selling books on ancient aliens in his "Chariots of the Gods" series. They were very popular with the geeks of my generation in the 1970s and 1980s The people who followed von Däniken's theories usually followed the overall genre of UFOs and conspiracy theories. I read all the Chariots of the Gods books, the books on Project Blue Book and UFOs, and whatever else I could find on what I collectively called strange science.

In the late 1970s I had a radio show where I discussed Project Blue Book and UFOs. Project Blue Book was one of a series of studies of unidentified flying objects (UFOs) conducted by the United States Air Force. Its ceased operations in January 1970 with the conclusion that there was no evidence that any of the sightings were extraterrestrial vehicles. With thousands of reports to analyze and hundreds of expert witnesses, the stories and conspiracy theories went on long after Project Blue Book was shut down.

I was happy to find my stash of books from the 1970s, as shown in the photo attached to this article. One of the books you see in the photo is "Strangest of All" by Frank Edwards, an American writer and broadcaster. Frank Edwards was a pioneer radio broadcaster in the 1920s through the 1950s, and a writer of a series of popular books about UFOs and "Strange Science."

I would buy a new book every week or two, as well as read about inventors and inventions in magazines like Popular Science or Popular Mechanics. Other than to talk about these topics with my friend, and read a few magazines, I did not have any way to really explore these topics in more detail. Back in the dark ages of the 1970s we did not have the internet to share ideas.  The stories have not changed since I first read them in the 1970s. What has changed is the new vehicle of the internet where myths and legends can take on a massive cult of followers.



Why believe in pseudosciences?

Many of the books on UFOs and ancient aliens are considered pseudoscience, meaning a false science, because they represent ideas and events that can not be validated by appropriate scientific methods. People imply that you are only intelligent if you believe in true science, and often make remarks that only an idiot would read a book classified as pseudoscience.

I can believe in the possibility of many ideas outside the realm of "conventional wisdom" without having to join the cult of a madman. I can believe there is the possibility of life on other planets without believing the information on the UFO websites telling me how aliens from other planets live among us. I can believe the government withholds key information from the public about world events without believing that every strange event is part of a government conspiracy. I spend a lot of time studying the lives of famous scientists and inventors, some of them have some pretty crazy ideas. An expression you will often see used is that there is a fine line between genius and insanity. There are times when we all walk along that line.

I am a believer in the statement made by Oliver Wendell Holmes, "Man's mind, once stretched by a new idea, never regains its original dimensions." There are many ideas which are considered pseudoscience that can be very interesting to study, and learning about them will definitely stretch your mind to a new dimension. That's why we are exploring myths and legends here at the World of Questy.

Spreading urban legends

Anytime someone sends me one of those amazing stories emails I often will research it. Before I tell a friend, post it to Facebook, or send it in an email, I like to know more about it. I love to hear about people doing cool things, especially something kind and generous. But if I want to hear about fictional crazy people and their wild adventures, I'll watch a Marvel comics movie. So many stores get passed off as factual, but no one ever does the simplest check of the facts.

Sometimes the answers, or the truth in the matter, is not clear cut. Sometimes a different story told from a different perspective can have a totally different look and feel to it. We can understand that. But some stories have nothing to validate them as being authentic, but for some reason they keep being told, simply because they are crazy or absurd.

Topics such as UFOs and conspiracy theories that were popular in various books and magazines in the 1970s and 1980s, are now generating a new wave of cult followers on the internet. Websites like YouTube can be an amazing place where you can learn a lot. People spend a lot of time creating great videos on how to do many things. On the other hand I have seen many videos on YouTube that were downright crazy in the amount of misinformation they were putting out. I can find thousands of YouTube videos on perpetual motion machines, 200 mpg carburetors, UFOs and aliens

Television shows like the X-files took topics like UFOs and conspiracy theories and carried them from themes followed by a few special interests into popular culture. We all now use the tagline "The Truth Is Out There", thanks to shows like the X-files.

The internet does not always record history, sometimes it creates it. Recently we added the page to Geekhistory.com, "Urban legend: I think there is a world market for maybe five computers." It is a topic I researched years ago as one of the many examples that gives merit to the point that the internet is a place that writes and recreates history based on public opinion, rather than just the facts. That is a major flaw in the artificial intelligence of search engines, specifically Google, who equate value with popularity. If thousands of websites tell us that IBM Chairman Thomas Watson said, "I think there is a world market for maybe five computers," in 1943, then it must be true. Doesn't it?

Learn the truth: "Urban legend: I think there is a world market for maybe five computers."

Delusional inventors plagued by conspiracies

Over at the website GeekHistory we look at inventors and inventions, exploring when visions became reality. There are a few cases where the myths and legends go deep beyond the history technology become crazy stories of cult followers and bizarre claims. Here at the World of Questy we look at methods and the madmen that take a question where where people have some doubt and create a sermon to answer the question. We look at the many scammers and false prophets that run off and turn an idea into a cult.

Sometimes it is hard to separate the theories of delusional inventors from their fanatic cult of followers who often rationalize the failures of their heroes with various legends of some conspiracy against them. Sadly, I see many people in search of answers who become members of various cults, and don't even realize it. I shake my head while reading comments on an online forum, I ask "can you tell me the exact source of your information." The commenter replies back, "I read it on the Internet."

There is a category of hucksters and outright frauds who we call the snake oil salesmen. In our next article we we explore the scams and hoaxes common in the old west that gave birth to the phrase Snake Oil as an all purpose cure for any problem.

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Why Nikola Tesla has become a cult hero

The World of Questy -

Every great epic story needs a hero and a villain. In the romanticized story known as the War of Currents, Thomas Edison is the villain. He is the guy everyone loves to hate. Nikola Tesla represents the hero we can identify with, the dreamer in all of us.

Nikola Tesla was a handsome well dressed fellow. He hung out at New York's finest restaurants rubbing elbows with the rich and famous. Tesla was an entertaining guy, he had cool party tricks, he invited the rich and famous back to his lab so he could shoot lighting bolts at them. He was a very interesting character.

Thomas Edison is portrayed as the cranky old fart with no sense of humor. Edison symbolizes the establishment. He is your high school science teacher who yelled at you for screwing up your lab assignment. He is the guy that your mother told you to be, why can't you be more successful, you know, why can you be more like Edison. But you never wanted to be like Edison, he looked like he was always working, and would be no fun at parties.

Tesla and Edison were both very influential during their lifetimes. Both men also had a wide variety of personality issues, both men were obsessive compulsive inventors who deserved to be respected, but not necessarily worshiped. If you read about Tesla, you will notice he was interviewed often for magazine articles during his lifetime. He was also a bit of a rebel. He poked fun at the scientists of his day, even dared to call Einstein names. He was an easy guy to like, and it was easy to portray Tesla as the underdog unafraid to take on the establishment.

The internet loves a good story, and the battle of good versus evil makes for a good story with Tesla representing the good, the forgotten misunderstood geek, and Edison representing the evil man who took advantage of the innocent Tesla. It is very sad that to make someone a cult hero, you need to tear someone down as well. Some of the remarks made about Edison are very disrespectful of his contributions to the world of technology. Likewise, men like George Westinghouse who worked with Tesla, as a partner not an adversary, are equally disrespected.

It is the classic story of good versus evil, and everyone roots for the good guy underdog to defeat the evil bad guy. Much of what is written about Edison being the Devil, and Tesla being a God, is based on myths and legends, not facts.



What's behind the cult following for Nikola Tesla?

I often get asked if the fascination with Nikola Tesla is a recent event. I have studied famous inventors and scientists since the 1970s. Different topics seem to rise and fall from time to time over the years. Topics such as UFOs and conspiracy theories were popular in various books and magazines in the 1970s and 1980s, are now being created as websites on the internet. It would appear that Tesla was equally popular in books and television shows, the things we amused ourselves with before the internet, by those who followed conspiracy theories and UFOs since at least the 1980s when I can personally reference the fascination with Tesla.

Even television shows like the X-files took topics like UFOs and conspiracy theories and carried them from themes followed by a few special interests into popular culture. We all now use the tagline "The Truth Is Out There", thanks to shows like the X-files. In the links below I have references to television shows from the 1980s and 1990s that cover Nikola Tesla.

But there is also an increase in the "cult following" of various types thanks to the internet, and especially websites like YouTube. YouTube can be an amazing place where you can learn a lot. People spend a lot of time creating great videos on how to do many things. In that regard I think YouTube can be amazing. On the other hand I have seen many videos on YouTube that were downright crazy in the amount of misinformation they were putting out.

I can find thousands of YouTube videos on perpetual motion machines, 200 mpg carburetors, UFOs and aliens. Likewise, I can search dozens of websites on these topics. Interesting that most of these, what I call "strange science" websites, have something about Nikola Tesla on them. He fits the mold of the mad scientist.

The internet does not always record history, sometimes it creates it. "The Truth Is Out There"

Nikola Tesla covered before the internet

The majority of books and movies made about Tesla are created by people who have a preconceived notion of Tesla, and are trying to prove their point. I am not condemning everyone who believes in conspiracy theories and the possibility of life on other planets, but the information that many of these sites provide is more in the quality of supermarket tabloids rather than non bias documentary journalism.

If you search for videos about Tesla on the internet you will also run across " Tesla - The Eye Of The Storm" produced around 1983. Many of the Tesla fanboy websites have links to calling it a "rare documentary" on U.S. Government conspiracies. It is rare only in the sense that you can't find any first hand information on it.

"Tesla - The Eye Of The Storm" is hosted by Stan Deyo, a host of similar shows on Australian television over the years on UFOs and what he calls "flying saucer technology." Unfortunately, every blog that talks about The Eye Of The Storm video references the Website of Stan Deyo, which currently looks like he is selling supplies and advice to prepare you for Armageddon.

I am cynical about a lot of the claims, I would love to see some references and resources for the origin of much of the so-called "facts" about Tesla's secrets. It appears that Tesla's story has been promoted by the same crowd who follows the UFOs and conspiracy theories for many years.

Leonard Nimoy hosted a "In Search of" television show (1976–1982) that investigated various mysteries. According to IMDB the "In Search of" television show was inspired by von Däniken's work. "This series was created after two successful television documentaries: In Search of Ancient Astronauts (1973) based on the book Chariots of the Gods, and In Search of Ancient Mysteries (1973)."

As far as I can tell Tesla's name never came up on the Leonard Nimoy "In Search of" television show, but Tesla's name was used in a book pitched at the same crowd who followed the UFOs and conspiracy theories. The book "In Search of Nikola Tesla" was originally published in 1983 by F. David Peat. It was reprinted again in 1997.

Book Reference: In Search of Nikola Tesla https://www.goodreads.com/book/show/10650961-in-search-of-nikola-tesla

Television Show Reference: In Search of... (TV Series 1976–1982)| http://www.imdb.com/title/tt0074007/

In 1998 the television show "Phenomenon: The Lost Archives " another show similar to "In Search of" aired two episodes related to Nikola Tesla. The show only aired 14 episodes in total. The two episodes on Tesla were:

- Season 1 | Episode 3 - H.A.A.R.P: Holes in Heaven (discusses Tesla's theories)
"Phenomenon: The Lost Archives" H.A.A.R.P: Holes in Heaven (TV Episode 1998) http://www.imdb.com/title/tt0412201/?ref_=ttep_ep3

- Season 1 | Episode 9 - Lost Lightning: The Missing Secrets of Nicola Tesla
"Phenomenon: The Lost Archives" Lost Lightning: The Missing Secrets of Nicola Tesla (TV Episode 1998) http://www.imdb.com/title/tt0898736/?ref_=fn_al_tt_9

Learn more at GeekHistory.com

We have been attacking the many myths and misinformation created by the internet through out our websites.  The strange life of Nikola Tesla often reads like a the science fiction story of a typical mad scientist.

Nikola Tesla the legacy of the most interesting geek in the world  (link is external)

Nikola Tesla versus Thomas Edison and the search for the truth (link is external)

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There is a sucker born every minute and they are using Google

The Tao of Questy -

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American circus entertainer P. T. Barnum is often credited with the statement "there's a sucker born every minute".  I was talking about another famous deputed phrase of P. T. Barnum a few months ago, "there's no such thing as bad publicity," in reference to Marketing 101 and how Pepsi succeeded. In my remarks about how Pepsi succeeded a photo that appears to show  P. T. Barnum with the quote "There's no such thing as bad publicity"  was attached to my posting.

Being an information geek I was curious to learn the origin of the photo of P. T. Barnum.  Doing a quick search of the image on Google quickly showed that the photo was not P. T. Barnum but famous psychologist Bertram R. Forer.

So if the image I think is P. T. Barnum is actually Bertram R. Forer, I ask Google for an image of P. T. Barnum. But now  I am confused, as I use Google to search on a photo of P. T. Barnum they look an awful lot like the same photos identified as Bertram R. Forer.

Bertram R. Forer's connection to P. T. Barnum

In 1948 psychologist Bertram R. Forer gave a psychology test to 39 of his psychology students. Similar to the P. T. Barnum statement "there's a sucker born every minute" Forer was looking to prove that when assessment statements are vague people read their own meaning into the statements. Basically Forer was trying to show that people are easily tricked or manipulated into believing vague things.
 

But Forer did not connect his theories to circus showman Phineas Taylor Barnum. The term "Barnum effect" referring to the the work of Forer was coined in 1956 by American psychologist Paul Meehl in his essay "Wanted A Good Cookbook".


Truth by consensus lies

In the world of Questy websites we have been critical of Google claims that "Democracy on the web works." The phrase "truth by consensus" describes the philosophical theory of taking statements to be true simply because people generally agree upon them.

I am cynical about the artificial intelligence of the internet, as I find examples of where truth by consensus is really a lie. Should I be reasonably certain that most of the photos Google identified as P. T. Barnum are accurate? If that is true, at this point I am not sure that I have found an accurate photo of famous psychologist Bertram R. Forer.

The more examples I find of truth by consensus like this mis-attributed photo of P. T. Barnum to Bertram R. Forer illustrates that there is a sucker born every minute and they are using Google to find the answers to their questions.

 


Truth by consensus and the myths and legends created by the internet | http://questy.com/content/truth-consensus-and-myths-and-legends-created-...

We've Got Something for Everyone: The Barnum Effect | https://www.psychologytoday.com/blog/sideways-view/201411/weve-got-somet...

F is for Bertram Forer | http://shootingparrots.co.uk/2017/02/15/f-is-for-bertram-forer/

P. T. Barnum | http://www.nndb.com/people/121/000056950/

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Privacy on the Internet is just wishful thinking

The Tao of Questy -

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It wasn't all that long ago that former NSA contract employee Edward Snowden was making news accusing the US government of accessing the web servers of some of the biggest internet services for the purpose of data mining, and WikiLeaks founder Julian Assange was becoming a cult hero for exposing government secrets.

Right now there are many arguments over net neutrality that stir up privacy issues into the mix, but they are another area in the fight to control the internet.

Recruiters research prospective candidates on social networking sites as part of pre-hire screening. Social media users have not all learned that the delete key is an illusion. The curse of the digital age is once information is accessed on the internet and passed on to others, there is no way to take it back.

Over at the Guru 42 Universe we talk about the great power comes great responsibility of the internet and the brave new online world. In spite of the fact that their use is increasing everyday, there is a growing distrust of social networking sites. Privacy and personal security concerns become hot topics as websites gather personal information for profiling users to enable advertisers to target them more productively. Ethical and legal concerns are raised as websites make money by selling our digital footprints.


Is privacy a thing of the past?

Back in 1999, Scott McNealy CEO and co-founder of Sun Microsystems uttered the famous quote, "You already have zero privacy. Get over it." Do you think things are any better nearly two decades later?

I know from a long career in telecommunications and computer networking, you have zero privacy.  I don't post my every move on Facebook, and I don't tweet from every restaurant I visit. But I don't go out of my way to run and hide either. I would rather you hear me pitch my view of who I am, instead of visiting one of the many websites offering to sell you anything you want to know about me. Even a simple search can turn up previous addresses and unlisted phone numbers.

I have been accused of blatant self promotion from time to time on social media. I admit to it. I feed the internet with information about me. I believe that a strong defense is to lead with a strong offense. That's not a football strategy, that's my view of dealing with social media.

I write about technology and politics, things like net neutrality, privacy issues, and attempts to regulate the internet. There are no easy answers to the issues. Many issues will involve understanding common ground and compromise.

Do you know who is watching you?

Are you using an email provider like Gmail? Did you know email stored on a third party's servers for over 180 days is considered to be abandoned, and law enforcement agencies only need to provide a written statement certifying that the information is relevant to an investigation in order to obtain the content of such emails. - See more at: Will the Email Privacy Act Become Law?

There are those who will tell you how you can hide your identity on the internet. I must really be cynical, because I wouldn't trust my life on that assumption, as explained in this Washington Post article: The NSA is trying to crack Tor. The State Department is helping pay for it. 

Is privacy just wishful thinking?

The technology generally exists to allow network managers to monitor all aspects of their computer system, including, monitoring sites visited by employees on the Internet, monitoring chat groups and news groups, reviewing material downloaded or uploaded by employees, and reviewing e-mail sent and received by employees.

Most Americans agree that the government should not infringe the individual’s right to privacy, property, and right to speak. But they also agree that law enforcement and national security are important governmental functions.  Interestingly enough, the word “privacy” does not appear in the Constitution.

Some follow up thoughts:

With Great Power Comes Great Responsibility

Protecting your assets balancing better security versus big brother

And a few more articles to get you thinking...

If You Think You're Anonymous Online, Think Again 

Most people don’t realize they are leaving behind digital footprints 

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What you need to know before buying a computer

Guru 42 Blog -

At last the secret of what you need to know before buying a computer is revealed, there is no one size fits all answer. But you don’t need to be a world class geek to learn computer buzzwords and understand some basic concepts before you shop for your next computer.

I usually try to stay out of the Apple versus Microsoft debates. Since I am updating some content on desktop operating systems on Computerguru.net I thought I would use this blog post to address the often asked question of "what computer should I buy" and add this perspective. I will also  introduce a few new articles to answer some frequently asked questions relevant to someone shopping for a computer.

Recently on an online forum the question of "what computer should I buy" was asked based on the idea that a MacBook Pro is inherently the best laptop out there. The person asking the question was looking for reasons to buy a MacBook Pro, but gave no clues on how they are going to use it. That is a very important factor in answering the question! I never answer any questions on "what computer should I buy" for friends and family until I ask several questions.

I laughed as I read one of the answers that stated, "If all you are going to do is web surfing, social media, and email you don’t need a MacBook Pro." Yea, that's right. There are Chromebooks as well as cheap Windows notebooks that could do that for a lot less money!

My best advice to anyone looking to buy a computer, think long and hard about how you are going to use it, and find other people with the same wants and needs, and ask them what they own, what they like and not like about it.

I am not a graphics designer or an artist, those are the type of users who are typically the Apple fans. I have been working in enterprise computer networking for more than 20 years, started working on desktop computers in the 1980s. I look at the computer as a tool, and I look at what is the best tool for the task at hand. I have no loyalties to any specific brands.

Many answers comparing Microsoft to Apple often use various luxury car to cheap foreign comparisons, implying if you could afford the expensive luxury car, but choose otherwise, you must be a fool. So let me run with that analogy.

Take a step back and look at the history of Apple versus Microsoft.  In the 1990s when Windows 95 dominated the desktop, Microsoft was the Ford F-150 pick up truck.  Not many people would describe the Ford F-150 pick up truck as a sexy luxury vehicle, but many would describe it as the work horse vehicle that gets the job done.  There's a good case to be made that the folks marketing to the pick up truck users have a different plan than those looking to sell the sexy luxury vehicle.

A computer is a tool I use for work, as well as recreation. I work in a business world that is Microsoft based. We are required to purchase a specific brand of Windows based computers, not my favorite brand, but that's my environment. My problems are no so much with Windows as it is the vendors that support our users create applications that run on old Microsoft operating systems. I have to deal with home cooked applications that are designed for last generation Windows computers. That's my world.

I have had iPads and various other Apple products in my home, and they never got used. Even if the interface is slightly different, I don't have time to deal with it. I have had access to Kindles and Nooks, and they never got used. I can put an application on my Windows notebook that reads the books, so why do I need to learn a new interface? It's called being lazy, I know it is, but I have no personal reason to care about Apple products. It's nothing personal.

If one of my family members wants to buy a luxury car, I will be happy to ride in it. If money were no object, tomorrow I would go out and buy a new Ford F-150 pick up truck that best suited my needs.

I don't get emotionally attached to my computers or automobiles. They are tools. Nothing more.

You too can understand computer buzzwords

Since 1998, ComputerGuru.net has attempted to provide self help and tutorials for learning basic computer and networking technology concepts, maintaining the theme, "Geek Speak Made Simple." Recently I updated the Drupal content management software for Computerguru and updated a few pages.

Based on commonly asked questions, I have added several new pages to the section Common technology questions and basic computer concepts. On computer operating systems we have added an article that explains the major differences between desktop computer operating systems and one on installing Linux and understanding all the different Linux distributions.

I get a lot a questions on computer cables and finally finished up this article on Ethernet computer network cable frequently asked questions answered and an article explaining computer network modular connectors and telephone registered jacks.

And based on many questions on printers, we had some fun coming up with this article, the ugly truth about computer printers.

Yes, I know that sounds like a lot of geek speak, but we do our best to break it all down into small bite sized chunks, so it is easy to digest.  Please take a few minutes to check out the new content, and please share it with your geek friends on social media.

Any topics need covered? Any questions missing?

Are there any buzzwords bothering you?  Something else you would like us to cover here at the Guru 42 Universe?  Let us know: Guru 42 on Twitter -|- Guru 42 on Facebook -|- Guru 42 on Google+ -|- Tom Peracchio on Google  

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Wireless Networks in Simple Terms WLAN and Wi-Fi defined

ComputerGuru -

The term Wi-Fi is often used as a synonym for wireless local area network (WLAN). Specifically the term "Wi-Fi" is a trademark of a trade association known as the Wi-Fi Alliance. From a technical perspective WLAN technology is defined by the Institute of Electrical and Electronics Engineers (IEEE).

In computer networking everything starts with the physical layer, which for many years was a copper wire. The physical layer was expanded to include anything that represent the wire, such as fiber optic cable, infrared or radio spectrum technology.

Wireless network refers to any type of computer network that is not connected by cables of any kind. While cell phone technology is often discussed as a form of wireless networking, it is not the same as the wireless local area network (WLAN) technology discussed here.

What is Wi-Fi?

The term Wi-Fi has often been used as a technical term to describe wireless networking. Wi-Fi is actually a trademark of the Wi-Fi Alliance, a global non-profit trade association formed in 1999 to promotes WLAN technology. Manufacturers may use the Wi-Fi trademark to brand products if they are certified by The Wi-Fi Alliance to conform to certain standards.

A common misconception is that Wi-Fi is an acronym of Wireless fidelity, it is not. The Wireless Ethernet Compatibility Alliance wanted a cooler name for the new technology as the IEEE 802.11b Alliance was not all that catchy. The marketing company Interbrand, known for creating brand names, was hired to create a brand name to market the new technology, and the name Wi-Fi was chosen. The term 'Wi-Fi' with the dash, is a trademark of the Wi-Fi Alliance.

IEEE 802.11 defines WLAN technology

The actual technical standards for wireless local area network (WLAN) computer communication are know as IEEE 802.11. IEEE refers to the Institute of Electrical and Electronics Engineers a non-profit professional association formed in 1963 by the merger of the Institute of Radio Engineers and the American Institute of Electrical Engineers.

IEEE 802 refers to a family of IEEE standards dealing with networks carrying variable size packets, which makes it different from cell phone based networks, 802.11 is a subset of the family specific to WLAN technology. Victor "Vic" Hayes was the first chair of the IEEE 802.11 group which finalized the wireless standard in 1997.

This link takes you to the 802.11 specification that contains all the geek speak on how it works. --> IEEE-SA -IEEE Get 802 Program
https://standards.ieee.org/about/get/802/802.11.html

How fast is Wi-Fi?

Wi-Fi speed is rated according to maximum theoretical network bandwidth defined in the IEEE 802.11 standards.

For example:

IEEE 802.11b - up to 11 Mbps

IEEE 802.11a - up to 54 Mbps

IEEE 802.11n - up to 300 Mbps

IEEE 802.11ac - up to 1 Gbps

IEEE 802.11ad - up to 7 Gbps

If you look at the IEEE 802.11 Wireless LANs standards you will see the ongoing evolution with several standards under development at this time to increase speeds even more.

Keep in mind that WiFi speed is how fast your internal network is, as in wireless LANs (Local Area Network)

Fast WiFi does not mean fast internet connection, it has nothing to do with the speed or bandwidth of you internet access.

How does Wi-Fi work?

A Wi-Fi enabled device such as a personal computer or video game console can connect to the Internet when within range of a device such as a wireless router connected to the Internet. wireless local area network (WLAN) technology allows your device to connect to the router, which in turn connects you to the internet.  In order to connect to the internet, you need a unique IP (internet protocol) address. On your home network, when your router is connected to the internet, it has a public address, that is the one that faces the internet, and is unique in relationship of other routers on the internet.

Your router also has a local IP Address of something like 192.168.1.2 and this is a private IP address space. Addresses beginning with 192.168 cannot be transmitted onto the public Internet and are typically used for home local area networks (LANs). If you have four home computers, your router creates a home network and the four home computers have a unique number in relationship to each other. Your local computers connect to the router, either by a wire plugged into the router, or through a wireless signal.

Routers are used to create logical borders between networks, and in this allow a gateway, such as an access point to the internet to be shared. In geek speak terms subnetting can be very complex, but what is happening here is the process know as subnetting.

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The ugly truth about computer printers

ComputerGuru -

The printer is the source of pain and problems for every computer user.  The ugly truth about computer printers is that everyone has one and they all stink.

A printer is very mechanical, there are a lot of moving parts.  Every printer from the very simplest, to the most complex, has numerous gears, springs, and rollers that all need to move in perfect harmony in order for your printer to work.  

In understanding why computer printers are a source of frustration, let me explain some of the other components of a typical computer system. On your home desktop computer you have a large box that everything plugs into. I hear people call this box a CPU, some call it a hard drive.  Technically the CPU is one small part on the main circuit board that sits inside that box.  The main circuit board, as well as the CPU and memory modules that plug into are solid state, that means they are all electronic. Unless you get hit with a power surge or some external electrical issue, it is rare that the electronics of a computer wears out over time. Even hard drives that once were very mechanical are now becoming solid state, which means no moving parts and much more reliable.

Same thing with your display, what we used to call a monitor.  Back in the days of CRT Monitors, the CRT (Cathode Ray Tube) wore out over time, it degraded because it heated up. In my experiences over the years I've seen some monitor failures. Not so much with modern displays, like the computer itself, they are now all electronic and less likely to degrade over time.

Things like keyboards and mice still have a few mechanical parts to them, but they don't wear out often.  When they do wear out, they are simple to replace, and people don't get too excited when they need replaced.

But alas, the printer, the pain of every computer user.  You just typed that report and you need it now.  You are leaving for the movies and you want to print the tickets, and the printer won't work.  There is never a convenient time for the printer to break.  

Even the simplest of printers has a handful of gears, springs, and rollers, that wear out over time.  The paper tray gets banged around every time you fill it up.  Every time someone takes out a paper tray, they bend something, they twist something, a part gets knocked off.  With the need to lower the cost of the printers, many of these mechanical parts are made from very low quality metal and plastic.

And here is one element of printers that many people over look, the paper.  When the air gets dry, when the heat is on in the winter, the paper gets full of static electricity, so it jams more often.  Instead of taking the paper out of the tray, fanning it a bit, flipping it over, you bang the paper tray a few times.  Maybe you yank the paper out when it jams, bending and stretching the metal arms and guides on the paper tray.

When the weather is damp and humid, that will also cause the paper to jam. Do you close the wrapper on your paper when it is just laying around?  Or is it just thrown on a shelf outside the wrapper?  I have seen many print quality issues caused by paper. Having spent a long career in office automation and computer networking I could write a book on the subject of printer problems because of paper.  The hardest part in answering this was keeping it brief.

Types of printing technology

Another issue you have with printers is consumable supplies like ink and toner. Every freaking printer model has its own unique ink or toner cartridge.  When you try to save money by refilling cartridges it is a crap shoot.  More often than not I have seen refilled cartridges cause many problems.

In the early days of desktop computers the dot matrix printer was the standard.  They could be pretty noisy as the small needles in the print head fired through the ribbon creating dots of information on your paper. Ribbons faded over time, and copy quality was not great, but printer ribbons were fairly inexpensive compared to modern ink cartridges. The boxes of paper with the tractor feed holes seems a little primitive compared to the plain paper printers of today, but in many ways the tractor feed paper was a more problem free solution than many of the modern printers with paper trays.

Inkjet printers began replacing dot matrix printers offering higher quality. A less noisy printer with higher quality could be a blessing, instead the inkjet technology was more of a curse. The color inkjet printer uses multiple color ink cartridge that includes a print head as a part of a replaceable ink cartridge that adds to the expense of the cartridge. The cartridges themselves have very narrow inkjet nozzles that are prone to clogging, and they dry out over time. New technology intelligent ink cartridges that communicate with the printer add another level of complexity, and another potential point of failure

Laser printers have been around since the very early days of desktop computers. They are high quality printers, but were for many years, very high cost.  In the early days it was rare to have a laser printer on your home computer, but over the years the quality has increased, and the price has dropped dramatically.  You can get a low cost black print laser printer for less than a hundred dollars. That is what I have in my home office, I have given up on low cost ink jet printers. Most of the times I use my home office laser printer to print a document such as a receipt, or maybe my tickets for a movie or sporting event, I don't need color for that.

The price of a laser printer toner cartridge sounds expensive, the last one I replaced was over $50, but they last ten times longer than an ink jet cartridge. If you look at it on a cost per copy basis, a laser printer is significantly cheaper to own than an ink jet. If I really need a high quality color copy, I can take a document on a USB drive to a local shop and get one there.

Prices have been dropping in recent years, and color laser printers cost a fraction of what they once cost.  If you need a color printer and print more than a few copies a month, do some calculations on the cost per copy of a color laser printer.  You might be surprised to see that over the long haul a color laser printer is not as expensive to own as an ink jet.

It's not your fault for buying a crappy printer

Between having a home computer system as well as working in the field of office automation and business machines since the early 1980s, I have worked with numerous brands of printers and printing equipment. It is hard to recommended a specific brand or specific model of printer at any time because they are constantly changing. In a marketplace that is always shopping for low cost, often a manufacturer will cut corners to lower costs, and a usually reliable brand will have some really horrible models.  

We are discussing the computer printer here as a hardware device, but software issues such as finding the proper drivers for your current computer operating and getting Wi-Fi to work on your network can also create problems. Shop wisely, read over consumer reviews of the currently popular printers to see the potential problems for a model you are considering buying.

The primary reason for a printer being the most likely part of your computer system to cause you pain comes down to the printer having the most moving parts, but there are also many other issues dealing with the supplies such as paper, ink, and toner. Maybe you won't feel any better about all the printing problems you are having after reading this article, but at least you will know, it's not your fault for buying a crappy printer, they all stink.

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Buzzwords from the world wide web to deep web and dark net

The Guru 42 Universe -

There are a lot of definitions that get thrown around about “the deep web” and “the dark web.” It is frustrating how people use the terms without a clue as to what they mean. The deep web and dark web are NOT synonyms!

Starting with defining "The Internet," think of all the wires and connections as a highway system. When I talk about the general term of the internet, I am speaking about the technologies that move packets of information along wires from one destination to another, specifically the family of protocols known as TCP/IP (transmission control protocol - internet protocol).

The "World Wide Web” represents the many destinations that are connected together using the public highway system of the internet. When I talk about the general term of the World Wide Web, I am speaking about the technologies that create websites and webservers such as HTTP (hypertext transfer protocol) and HTML (hypertext markup language).

Where it gets confusing is how you apply the usage of the terms. Sometimes when people say "the internet" they are not describing just the highway system, but they are using the term to represent all the websites in existence. Likewise, often when people say “The World Wide Web” they use it to mean all the websites in existence.

The technology that the internet uses on the public highway, things like the internet protocols like TCP/IP and World Wide Web components HTTP and HTML, can also be used to take us to private destinations as well. This collection of private destinations is known as the "Deep Web." Computer scientist Michael Bergman, founder of search indexing specialist company Bright Planet is credited with coining the term deep web in 2001 as part of a research study.

In 2014, a Forbes article, "Insider Trading On The Dark Web"(1), completely confuses the terms and misquotes the definitions of BrightPlanet CEO Michael Bergman and incorrectly describes Bright Planet as "a firm that harvests data from the Dark Web." In response to confusion about the terms Deep Web versus Dark Web BrightPlanet published the article, "Clearing Up Confusion – Deep Web vs. Dark Web." (2)

The link to the BrightPlanet article is listed at the end of this article, but here are a few points from that article which define the main points.

- "The Surface Web is anything that can be indexed by a typical search engine like Google, Bing or Yahoo."
- "...the Deep Web is anything that a search engine can’t find."
- "The Dark Web then is classified as a small portion of the Deep Web that has been intentionally hidden and is inaccessible through standard web browsers."
- "The key thing to keep in mind is the Dark Web is a small portion of the Deep Web."



Why does the "deep web" have much more content than the "regular web" since it's used by far fewer people?

Here's an analogy that might help you understand why there is so much more information "below the surface" on private networks, than above the surface on public networks.

Go to the downtown of an average city where you can find a variety of commercial office buildings. Some of the buildings have a lobby, where you can go inside and walk around. Some buildings might actually have a common area where the general public can walk around freely and access various bits of information, like the lobby of a bank or insurance company. But on the floors above the lobby are offices which require special privileges to access, you must have a need to get into these rooms.

Likewise, you might have a government building where the first floor might contain a post office or some other public service agency that anyone can access. But the floors above it could contain other types of offices where admission is restricted, or accessed by invitation only.

In your downtown area, how many of the buildings can you walk around freely, and how many have controlled access? Are there buildings that you can not walk around in at all because they are privately owned and don't allow access to the general public?

I could expand the analogy further, but hopefully you start to see that in the "real world" of your downtown area there will places that are open to the public, and other areas with various degrees of access limitations. Likewise in the virtual world of the web, there there will places that are open to the public, and other areas with various degrees of access limitations.

The deep web does not mean some dark and mysterious place of evil, it is simply a term describing an area of controlled access rather than free and open access.

What is the dark web and how do you access it?

Going back to the analogy that the deep web represents the buildings in your town that don't allow access to the general public, the dark web represents all the back alley doorways that are not clearly marked and are accessed by knowing what to say to the doorman to gain access to what is inside.

The worldwide network known as “the dark web”uses specially configured servers designed to work with custom configured web browsers with the purpose of hiding your identity. You will see the term Tor servers and web browers to describe this private network. Tor originally stood for "The Onion Router."

Tor receives funding from the American government but operates as an independent nonprofit organization. The dark web is an interesting place as described in a Washington Post article that explains how the NSA is working around the clock to undermine Tor's anonymity while other branches of the federal government are helping fund it.(3)

A Wired article explains how WikiLeaks was launched with documents intercepted from Tor.(4) You can follow this link to an interview with former government contractor Edward Snowden (5) explaining how Tor is used to create private communications channel.

What can you find on the dark net?

The mysterious dark web, sometimes called the dark net, is the fuel for spy movies. it helped to create WikiLeaks run by the super spy Julian Assange and it allows cyber snitches like Edward Snowden share secret information.

Because the dark net is hidden, and the people that are hiding are doing their best not to be found, knowing the what goes on in the dark can be as mysterious as the name implies. For example one study that claims that nearly half of the sites on the dark net are not doing anything illegal.(6) But a different study that claims that 80% of dark net traffic is related to child abuse and porn sites.(7)

Various names have been used to describe the dark net such as the black internet, to suggest it is the home of online black markets. And the claims of the black internet are supported when a well know online drug black market gets busted. (8)

But does anyone really know what we could find on the dark net? What could you find in your city if you started knocking on doors in dark alleys? Would you want to guess?

Learn more:

Internet and World Wide Web visionaries ponder surviving world war

Who invented the world wide web?

References:

(1) Insider Trading On The Dark Web https://www.forbes.com/sites/realspin/2014/03/25/insider-trading-on-the-dark-web/

(2) Clearing Up Confusion – Deep Web vs. Dark Web. https://brightplanet.com/2014/03/clearing-confusion-deep-web-vs-dark-web/

(3) The NSA is trying to crack Tor. The State Department is helping pay for it.
https://www.washingtonpost.com/news/the-switch/wp/2013/10/05/the-nsa-is-trying-to-crack-tor-the-state-department-is-helping-pay-for-it/

(4) WikiLeaks Was Launched With Documents Intercepted From Tor
https://www.wired.com/2010/06/wikileaks-documents/

(5) This is What a Tor Supporter Looks Like: Edward Snowden
https://blog.torproject.org/blog/what-tor-supporter-looks-edward-snowden

(6) Research suggests the dark web is not as dark as we think
http://www.htxt.co.za/2016/11/02/research-suggests-the-dark-web-is-not-as-dark-as-we-think/

(7) Study claims more than 80% of 'dark net' traffic is to child abuse sites
https://www.theguardian.com/technology/2014/dec/31/dark-web-traffic-child-abuse-sites

(8) "End Of The Silk Road: FBI Says It's Busted The Web's Biggest Anonymous Drug Black Market"
https://www.forbes.com/sites/andygreenberg/2013/10/02/end-of-the-silk-road-fbi-busts-the-webs-biggest-anonymous-drug-black-market/

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Everything you need to know about Ethernet and computer cabling

The Guru 42 Universe -

The concepts of Ethernet and computer network cabling are so full of buzzwords and geek speak. We wanted to break down the jargon into bite sized chunks to help you understand the concepts. 

Everything in computer networking starts at the physical layer, that's where the wires plug into the boxes with blinking lights. Because Ethernet deals with wires at the physical layer, at times Ethernet becomes a generic word for any type of wire associated with a computer network.

We created this section of business success beyond the technology buzzwords at the Guru 42 Universe based on conversations we had with business professionals as well as technology professionals. In discussing technology from the perspective of a business owner or business manager we realize you don't have time to become a network engineer, but we also understand your frustration in understanding all the buzzwords. With those thoughts in mind we created this introductory page on defining the term Ethernet and explaining computer network cabling.

In designing ComputerGuru we break down the topics from the perspective audience of the person asking the questions. At our ComputerGuru site we have the section, Common technology questions and basic computer concepts, which is aimed at the typical home computer user.  

Even a non technical casual user of a personal computer has probably heard of the term Ethernet from time to time.  Likewise, the typical computer user has probably misplaced a piece of wire used to connect their computer and went off in search of a network cable.  As an introduction to Ethernet and computer network cabling we have created the following pages: Ethernet computer network cable frequently asked questions answered and Computer network modular connectors and telephone registered jacks.

The strict technical definition of Ethernet is a physical and data link layer technology for local area networks (LANs). If you want to dig deeper into the technology, in our section targeted to learning computer networking technology we have the section, Basic network concepts and the OSI model explained in simple terms.  In that section The Physical Layer of the OSI model discusses the more technical terms of data communications.  The concept of Ethernet is more than just defining wires and connections, and that is discussed as part of the The Data Link Layer of the OSI model.

Any topics need covered? Any questions missing?

Are there any buzzwords bothering you?  Something else you would like us to cover here at the Guru 42 Universe?  Let us know: Guru 42 on Twitter -|- Guru 42 on Facebook -|- Guru 42 on Google+ -|- Tom Peracchio on Google  

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Computer network modular connectors and telephone registered jacks

ComputerGuru -

The plastic plugs on the ends of telephone wiring and computer cables are defined by various technical standards. Because these standards are full of technical definitions and acronyms, it is easy to see how street slang becomes the accepted definition for many of the plastic plugs.

It is important to understand that connecting devices together is more than just matching up connector ends on a piece of wire. Just because you can find an adapter to make your cable fit into a connection is no guarantee that the device will communicate on your network. Some connectors that look exactly alike could have different wiring configuration.

In the world of technology street slang, or common buzzwords, often become the accepted the description of something rather than the specific technology standard. For example describing Ethernet patch cables as using RJ45 connectors illustrates one of the most mis-used terms in the world of technology.

We will do our best to break down some of the buzzwords and jargon to help you understand the differences in the terms.

Modular connectors

A modular connector is an electrical connector that was originally designed for use in telephone wiring, but has since been used for many other purposes. Many applications that originally used a bulkier, more expensive connector have converted to modular connectors. Probably the most well known applications of modular connectors are for telephone jacks and for Ethernet jacks, both of which are nearly always modular connectors.

Modular connectors are designated with two numbers that represent the quantity of positions and contacts, for example the 8P8C modular plug represents a plug with having eight positions and eight contacts.

Do not assume that connectors that look the same are wired the same. Contact assignments, or pin outs, vary by application. Telephone network connections are standardized by registered jack numbers, and Ethernet over twisted pair is specified by the TIA/EIA-568 standard.

Telephone industry Registered Jack

A Registered Jack (RJ) is a wiring standard for connecting voice and data equipment to a service provided by a telephone company. In some wiring definitions you will see references to the Local Exchange Carrier (LEC), which is a regulatory term in telecommunications for the local telephone company.

Registration interfaces were created by the Bell System under a 1976 Federal Communications Commission (FCC) order for the standard interconnection between telephone company equipment and customer premises equipment. They were defined in Part 68 of the FCC rules (47 C.F.R. Part 68) governing the direct connection of Terminal Equipment (TE) to the Public Switched Telephone Network (PSTN).

Connectors using the distinction Registered Jack (RJ) describe a standardized telecommunication network interface. The RJ designations only pertain to the wiring of the jack, it is common, but not strictly correct, to refer to an unwired plug by any of these names.

For example, RJ11 is a standardized jack using a 6P2C (6 position 2 contact) modular connectors, commonly used for single line telephone systems. You will often see telephone cables with four wires used for common analog telephone referred to as RJ11 cables. Technically speaking RJ14 is a configuration for two lines using a six-position four-conductor (6P4C) modular jack

RJ45 is a standard jack once specified for modem or data interfaces using a mechanically-keyed variation of the 8P8C (8 position 8 contact) body. Although commonly referred to as an RJ45 in the context of Ethernet and category 5 cables, it is incorrect to refer to a generic 8P8C connector as an RJ45.

Why is a Ethernet eight-pin modular connector (8P8C) not an RJ45?

Both twisted pair cabling used for Ethernet and the telecommunications RJ45 use the 8P8C (Eight Position, Eight Contact) connector, and there lies the confusion and the misuse of the terms. The 8P8C modular connector is often called RJ45 after a telephone industry standard. Although commonly referred to as an RJ45 in the context of Ethernet and Category 5 cables, it is incorrect to refer to a generic 8P8C connector as an RJ45

The 8P8C modular connector is often called RJ45 after a telephone industry standard defined in FCC Part 68. The Ethernet standard is different from the telephone standard, TIA-568 is a set of telecommunications standards from the Telecommunications Industry Association (TIA). Standards T568A and T568B are the pin - pair assignments for eight-conductor 100-ohm balanced twisted pair cabling to 8P8C (8 position 8 contact) modular connectors.

How does a RJ45 to RJ11 converter work?

There is no such thing as a RJ45 to RJ11 converter. They are two different types of connectors for two totally different standards of communication. Cables with various pin configurations and wire pairs are created for specific purposes. Be careful when looking to "convert" on type of wire into another. An adapter that allows you to connect an RJ11 plug into an RJ45 plug is not converting anything.

Technically speaking neither RJ11 or RJ45 is a computer networking standard. Many times when people are looking to convert between RJ11 and RJ45 they are dealing with a device made for a two wire phone line and trying to connect it to an Ethernet eight-pin (8P8C) unshielded twisted-pair (UTP) modular connectors.

I see many questions on internet forums asking about various adapters and converters. Just because you can convert a plug from one type to another does not mean that the signal traveling along the wire will work as you expect. I can not stress enough the importance of not using any type of adapters and converters without knowing the exact wiring configuration of the devices you are trying to connect.

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Ethernet computer network cable frequently asked questions answered

ComputerGuru -

You will often hear a common computer network patch cable called an "Ethernet cable." While most modern local area networks (LAN) use the same type of cable, the term Ethernet is a family of computer networking technologies that defines how the information flows through the wire, but does not define the physical network cable.

The standards defining the physical layer of wired Ethernet are known as IEEE 802.3, which is part of a larger set of standards by the Institute of Electrical and Electronics Engineers Standards Association.

Cable types, connector types and cabling topologies are defined by TIA/EIA-568, a set of telecommunications standards from the Telecommunications Industry Association (TIA). The standards address commercial building cabling for telecommunications products and services.

Computer network cabling

Twisted Pair Cabling is a common form of wiring in which two conductors are wound around each other for the purposes of canceling out electromagnetic interference which can cause crosstalk. The number of twists per meter make up part of the specification for a given type of cable.

The two major types of twisted-pair cabling are unshielded twisted-pair (UTP) and shielded twisted-pair (STP). In shielded twisted-pair (STP) the inner wires are encased in a sheath of foil or braided wire mesh. Unshielded twisted pair (UTP) cable is the most common cable used in modern computer networking.

What does Cat5 Cable mean?

A Category 5 cable (Cat5 cable) is made up of four twisted-pair wires, certified to transmit data up to 100 Mbps. Category 5 cable is used extensively in Ethernet connections in local networks, as well as telephony and other data transmissions.

Cat5 Cable has been the standard for homes and small offices for many years. As technology for twisted pair copper cabling has progressed, successive categories have given buyers more choices. Category 5e and Category 6 cable offer more potential for bandwidth and better potential handling of signal noise or loss. Newer cable types also help to deal with the issue of cross talk or signal bleeding, which can be problems with unshielded twisted pair cabling.

The category 5e specification improves upon the category 5 specification by revising and introducing new specifications to further mitigate the amount of crosstalk.The bandwidth (100 MHz) and physical construction are the same between the two.

The category 6 specification improves upon the category 5e specification by improving frequency response and further reducing crosstalk. The improved performance of Cat 6 provides 250 MHz bandwidth and supports 10GBASE-T (10-Gigabit Ethernet). The Cat 6 cable is fully backward compatible with previous versions, such as the Category 5/5e

Older versions of voice and data cable

Category 1 Traditional UTP telephone cable can transmit voice signals but not data. Most telephone cable installed prior to 1983 is Category 1. Category 2 UTP cable is made up of four twisted-pair wires, certified for transmitting data up to 4 Mbps. Official TIA/EIA-568 standards have only been established for cables of Category 3 ratings or above.

Category 3 was widely used in computer networking in the early 1990s for 10BASE-T. In many common names for Ethernet standards the leading number (10 in 10BASE-T) refers to the transmission speed in Mbit/s. BASE denotes that baseband transmission is used. The T designates twisted pair cable.

Category 4 cable consists of four unshielded twisted-pair (UTP) copper wires used in telephone networks which can transmit voice and data up to 16 Mbit/s. Category 4 cable is not recognized by the current version of the TIA/EIA-568 data cabling standards.

What does Patch Cable mean?

A patch cord, also called a patch cable, is a length of cable with connectors on each end that is used to connect one electronic device to another. In computer networking what people often call an “Ethernet Cable” is Unshielded Twisted-Pair (UTP) patch cable.

What does Straight-Through Cable mean?

A straight-through cable is a standard patch cable used in local area networks. Straight-through cables have the wired pins on one end match on the other end. In other words, pin 1 on one end is connected to pin 1 on the other end, and the order follows the straight through route from pin 1 through pin 8.

What is a Crossover Cable?

A crossover cable is used for the interconnection of two similar devices. It is enabled by reversing the transmission and receiving pins at both ends, so that output from one computer becomes input to the other, and vice versa. The reversing or swapping of cables varies, depending on the different network environments and devices in use.

This type of cable is also sometimes called a and is an alternative to wireless connections where one or more computers access a router through a wireless signal. Use a straight-through cable when connecting a router to a hub, a computer to a switch, or connecting a LAN port to a switch, hub, or computer.

Why do you need a crossover cable?

A traditional port found in a computer NIC (network interface card) is called a media-dependent interface (MDI). A a traditional port found on an Ethernet switch is called a media-dependent interface crossover (MDIX), which reverses the transmit and receive pairs. However, if you want to interconnect two switches, where both switch ports used for the interconnection were MDIX ports, the cable would need to be a crossover cable.

Introduced in 1998, Auto MDI-X made the distinction between uplink and normal ports and manual selector switches on older hubs and switches obsolete. Auto MDI-X automatically detects the required cable connection type and configures the connection appropriately, removing the need for crossover cables.

Gigabit and faster Ethernet links over twisted pair cable use all four cable pairs for simultaneous transmission in both directions. For this reason, there are no dedicated transmit and receive pairs, and consequently, crossover cables are never required.

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Marketing 101 and how Pepsi succeeded

The Tao of Questy -

Body: 

With everything going on in the world it is amazing that the social media crowd is all wound up over a Pepsi advertisement. While there are those who rant just how stupid the Pepsi advertisement was, "How did Pepsi's ad even get off the drawing board?"(1) there are others who understand the nature of marketing stating that "Pepsi's New Ad Is a Total Success"(2)

Why all the outrage?


In a world at war, with so many problems, there are more worse things happening that need discussion than a television commercial.

I doubt that any one single television advertisement is going to make me switch political parties, likewise with my favorite sports teams, I won't switch.

I hate political labels, does it really matter if Republicans and Democrats started the debate, as long as there is a solution to the problem? Next to who is my favorite sports team and what political party I claim as my own, the next most polarizing topic in America might be, do I prefer Pepsi over Coke.

As far as Coke or Pepsi, I have my mind made up. But to a certain extent, whether I drink Coke or Pepsi is somewhat determined by where I eat. Most restaurants serve Coke or Pepsi, very few sell both.

Go ahead boycott Pepsi

There are a few rants on social media proclaiming, "PepsiCo has made its last dollar off of me."

The people who never liked Pepsi, and the haters that hate capitalism and blame it for all our evils will now tell us all how we need to boycott this evil company.

PepsiCo, Inc. is an American multinational food, snack and beverage company. If you feel the need to boycott Pepsi make sure you add Fritos, Cheetos, Tostitos, and Doritos, to your list of things to boycott.

If you are eating out, avoid Pepsi spinoffs KFC, Taco Bell, and Pizza Hut. At breakfast time you will need to avoid Tropicana, Quaker Oats, Life cereal, and Captain Crunch as well if you really want to show Pepsi who is boss!

Pepsi succeeded!


If Pepsi had produced a silly commercial and everyone ignored it, another day passes and no one notices it. But Pepsi has received a tremendous amount of attention, and chatter on the internet because of this controversy.

According to Google Trends, on average the internet interest for Coke is twice as much as Pepsi, that is until the last few days when people talking and posting about Pepsi has skyrocketed. Pepsi's mentions on social media were up more than 7,000% the day the Kendall Jenner ad debuted, according to Brandwatch, a social media analytics company. Brilliant marketing move by Pepsi!


"There's no such thing as bad publicity." - P. T. Barnum

 

(1) How did Pepsi's ad even get off the drawing board?  https://www.usatoday.com/story/money/2017/04/06/pepsis-ad-diversity/100133470/


(2) Pepsi's New Ad Is a Total Success https://www.theatlantic.com/technology/archive/2017/04/pepsi-ad-success/522021/

 

 

 

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Installing Linux defining distros which version should you choose

ComputerGuru -

In April 1991, Linus Torvalds, at the time a 21 year old computer science student at the University of Helsinki, Finland, started working on some simple ideas for an operating system. Although the desktop computer market exploded throughout the 1990s, the Linux Operating System remained pretty much the domain of geeks who like to build their own computers. I really believed that more than 20 years later we would have Linux computers in our home as common as Windows or Apple varieties.

The only dent in the domination of Windows or Apple desktop computers in recent years has been the introduction of the Chromebook as a personal computer in 2011. The Chrome operating system is a strange mix of the Linux kernel and using the Google Chrome web browser as a user interface.

The Linux operating system has come a long way since the mid 1990s. From painful experiences with using floppy disks and hunting down hardware drivers, my experiences with installing many distributions of Linux in recent years has been pretty painless.

The Linux kernel

Just as I did with answering the question, "what is the best desktop computer operating system," I am going to generalize a bit here so we don't get too deep into the geek speak. Hopefully the tech purists won't beat me up too much for generalizing. Let's begin with quickly going over the basic definitions.

Think of the Linux kernel as an automobile engine and drive train that was designed by a community. Once the engine and drive train have been developed there are groups that split off and design their own version of an automobile. Each of these automotive design groups have their own community with goals for how they want to use their finished product, some may focus on style and looks, another group may want to focus on being practical and functional. Once the group has a general purpose in mind, they will form an online community where they can share ideas in creating a finished product.

The Linux Distro

Each customized version of Linux that adds additional modules and applications is supported by an online community offering internet downloads as well as support. You will see the question phrased as which Linux distro should you use. Distro is a shortened version of the term distribution. There are many distros of the Linux family all based on the same Linux kernel, the core of the computer operating system. There are geeks who swear by which is the best Linux distro, but in the end it is a matter of what works best for you.

When it comes to comparing the various distributions, I find "the big three" to be very similar, because in reality they are variations of the same family. As of the time of this update, March 2017, based on various statistics the most popular version of Linux is Mint, with Debian coming in second, followed by Ubuntu. Mint is a fork from Ubuntu, which is itself a fork from Debian. Mint is very similar indeed to Ubuntu. Mint was forked off Ubuntu with the goal of providing a familiar desktop graphical user interface.

First answer the question, why are you looking at Linux? Do you have an old computer with an outdated operating system that you are looking to upgrade? Or perhaps you just want to see what all the fuss is about with the "free" alternative to Windows or Apple?

If you simply want to play with Linux and just want to see what all the fuss is about, Mint is a very easy place to start. I have installed Mint on a few old computers with no issues. One of the biggest issues I have experienced with many versions of Linux is the lack of drivers for certain pieces of hardware in some laptop models. There's a few old Dell laptops I moved on from installing Linux because finding drivers for the Wi-Fi was not worth the effort.

Here's a look at various distributions of Linux.

In our previous question on "what is the best desktop computer operating system" we addressed the topic of the "free" alternative to Windows or Apple as we explained Open Source software. Richard Stallman, the father of the Open Source software movement, explains that Open Source refers to the preservation of the freedoms to use, study, distribute and modify that software, not zero-cost. In illustrating the concept of Gratis versus Libre, Stallman is famous for using the sentence, "free as in free speech not as in free beer." Even though Linux is open source there are versions that are commercially distributed and supported.

Fedora - Red Hat

Red Hat Commercial Linux, introduced in 1995, was one of the first commercially supported versions of Linux, and entered into the enterprise network environment because of its support. Red Hat Linux has evolved quite a bit over the years as Red Hat Linux merged with the community based Fedora Project in 2003.

Fedora is now the free community supported home version of Red Hat Linux. Fedora ranks slightly behind the other distros we mention here in popularity, Fedora is often at the top of list when it comes to integrating new package versions and technologies into the distribution. Many users in the enterprise environment rave about the stability of Fedora.

SUSE - openSUSE

openSUSE claims to be "the makers' choice for sysadmins, developers and desktop users." You may not find a lot of neighborhood geeks telling you to try openSUSE but it ranks near the top of many charts as far as popularity. SUSE was marketing Linux to the enterprise market in 1992, before Red Hat. Many American geeks are not as familiar with SUSE because it was developed in Germany. I have not had any issues with installing it. You can always download a "live CD" which allows you to run the operating system off of the CD without having to install it

openSUSE is the open source version. SUSE is often used in commercial environments because professional help is available under a support contract through SUSE Linux. Having worked as a Novell Netware systems administrator I was involved with SUSE Linux as the Novell Netware network operating system was coming to the end of its life when Novell bought the SUSE brands and trademarks in 2003. When Novell was purchsed by The Attachmate Group in 2011, SUSE was spun off as an independent business unit. SUSE is geared for the business environment with SUSE Linux Enterprise Server and SUSE Linux Enterprise Desktop. Each focuses on packages that fit its specific purpose.

Debian - Ubuntu - Mint

Ubuntu and Mint are Debian-based: their package manager is APT (The Advanced Package Tool) a free software user interface that works with core libraries to handle the installation and removal of software on the Debian Linux distributions. Their packages follow the DEB (Debian) package format.

Ubuntu is often used in commercial environments because professional help is available under a support contract through Canonical, the company behind Ubuntu.

Mint is basically the same OS as Debian or Ubuntu with a different default configuration with a lot of pre-installed applications and a nice looking desktop. Mint was forked off from the Ubuntu community with the goal of providing a familiar desktop Operating System.  If you are looking for something to use as a server Debian or Ubuntu may be a better choice.


What about all the rest?

There are more that 200 different versions of Linux. Once you go beyond the versions mentioned here you are getting into support issues. With each of the three families of Linux we mention here, there is a commercially supported version and a community supported version. Keep in mind, if you are not buying support through one of the commercial versions mentioned here, each of these families have a well established online community for support of the open source version.

Is it time to switch to Linux?

Back in the late 1990s I was taking a community college course on Novell networking and systems administration using Novell Netware. As part of the curriculum we had to write a term paper on a unrelated technology topic, I chose Linux on the desktop. I concluded that I was impressed with Linux as an operating system, but it would not become mainstream desktop operating system until there were hardware companies embracing it and selling home computers with Linux installed. Twenty years later, that really has not happened.

You could make the case that the Google Chromebook is a version of Linux installed and configured along with a computer, but the Google Chromebook has not become a mainstream home computer. If all you want to do is surf the net, interact on social media, and read your email, a Google Chromebook works fine. But beyond that there are many issues.

Hardware drivers and website plugins can be a problem when using any version of Linux. Many manufacturers don't develop Linux device drivers for their hardware, you need to search them out yourself through your LInux community. Using many websites that need Digital Rights Management, like Amazon Video, Netflix, or Sling, getting your streaming to work on Linux can be difficult. Some websites don't understand Linux as an operating system and automatic installs of plugins fail.

I know I said at the beginning of this discussion that in recent years my experinece in installing Linux has been pretty painless, but I have access to name brand hardware on pretty basic computers.  The problem with hardware drivers and browser plug ins keeps improving, but beware it can be an issue at times.  It is still a concern that can turn your Linux experince sour. The biggest problem I have experienced in experimenting with Linux is network card and WiFi drivers in laptop models.

In our last article we discussed why is Microsoft Windows so popular. Whether you love them or hate them, many applications only have a Windows version. There are many websites that offer "open source equivalents” to your favorite applications. Some equivalents work well, others are very buggy. The key to using any open source application is looking at how active is the community that supports them. Be cautious of applications that look cool and work well, but are basically created and supported by a single individual. They can often become unsupported as developer creates an application and moves on without supporting it over time.

Take Linux for a test drive

Look for a live distribution of Linux that allows you to run a full instance of the operating system from either CD, DVD, or USB, without making changes to your current system. Many install downloads will offer you a live test drive of the distro that does not install anything to your hard drive. If everything works well from a live test drive, you can feel a bit more comfortable about doing the "real" install.

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Desktop personal computer system basic parts defined

ComputerGuru -

If you are studying personal computers as the beginning of your career in technology, or perhaps you are just trying to understand how things work on your home computer to better deal with problems and upgrades, you can't get away with not knowing some very basic definitions of the components of a desktop personal computer system.

There have been so many types of hardware and software over the years, keeping up to date on what is current is a full time job for many computer support technicians. This section is meant to be a brief introduction to common personal computer terms, we are only introducing you briefly to the basics.

If you are interested to learn more, many of the topics described here are covered in more detail throughout the websites of the Guru42 Universe. Over at our sister site GeekHistory.com we explore the history of technology and the evolution of personal computers.

Basic parts defined

Computer hardware is the collection of physical elements that make up a computer system such as a hard disk drive (HDD), monitor, mouse, keyboard, CD-ROM drive, network card, system board, power supply, case, and video card.

The main system board is sometimes called the motherboard. It is the central printed circuit board (PCB) in and holds many of the crucial components of the system, providing connectors for other peripherals.

The central processing unit (CPU), the brain of a computer system is the main component on the main system board. The CPU carries out the instructions of computer programs, performs the basic arithmetical, logical, and input/output operations of the system.

System boards will have expansion slots, a CPU socket or slot, location for memory cache and RAM, and a keyboard connector. Other components may also be present. A slot is a narrow notch, groove, or opening. A socket is a hollow piece or part into which something fits. Systemboards contain both sockets and slots, which are the points at which devices can be plugged in. A CPU slot is long and narrow while a CPU socket is square.

RAM (Random Access Memory), is the computer's primary storage which holds programming code and data that is being processed by the CPU.

ROM is read-only memory. ROM chips, located on circuit boards, are used to hold programming code that is permanently stored on the chip.

Flash ROM can be reprogrammed whereas regular ROM cannot be. In order to change the programming code of regular ROM, the chip must be replaced. Upgrades to Flash ROM can be downloaded from the Internet.

BIOS stands for basic input-output system. It is used to manage the startup of the computer and ongoing input and output operations of basic components, such as a floppy disk or hard drive.

Software

Computer software is a collection of computer programs and related data that provide the instructions for telling a computer what to do.

System software provides the basic functions for computer usage and helps run the computer hardware. An operating system is a type of software that controls a computers output and input operations, such as saving files and managing memory. Common operating systems are typically Windows based, but personal computers can also use an Apple or Linux based operating system as well.

Software applications represent a variety of computer programs. Some applications such as computer games are for the entertainment of the computer user. Other applications such as word processors are used for creating documents or spreadsheet programs that are computerized simulations of paper accounting worksheets.

Data storage

The term data is used to describe the files created by the applications. On the typical home computer you have various data files such as the documents created by your word processors, as well as music and movies that you have downloaded in the form of various types of audio and video files.

There are many types of data storage devices. A hard disk drive (HDD) is called secondary storage while memory is called primary storage because programs cannot be executed from secondary storage but must first be moved to primary storage. Basically, the CPU cannot "reach" the program still in secondary storage for execution.

As the personal computer has evolved over the years, so has the many forms of storage devices used to remove the data from your computer for storage. Early home computers had floppy disk drives which used various forms of diskettes based on magnetic storage.

The next generation of data storage devices were optical disc technologies, first with the Compact disc (CD) and later with the digital versatile disc (DVD).

USB flash drives are now commonly used for storage, data back-up and transfer of computer files. The USB flash drive has been replacing all other forms of data storage devices in recent years.

Peripherals

A home computer system is a combination of hardware and software components. Computer hardware describes the physical parts or components of a home computer system.

Computer peripherals are various devices used to put information into and get information out of your computer. Keyboards, mouse, scanners, digital cameras and joysticks are examples of input devices. Displays, printers, projectors, and speakers are examples of output devices.

What is the difference between a PC (personal computer) and a workstation

In a business environment you may have a computer on your desk that is very similar to the computer you have at home, but there is one major difference, the work computer is managed as part of a LAN (local area network) that contains many other computers. In the next section we define networking terms and go into a bit more detail on the concept of a LAN.

Some definitions will state that a workstation computer is faster and more powerful than a personal computer. Not necessarily. Terms like "faster and more powerful" are pretty ambiguous. The difference is a bit more clear-cut, it is a point of reference in how they are used.

In your home you have a personal computer, it is the center of your personal technology universe. When you open up an application, it is on that computer. When you create a data file, like a Word document, you save it to that computer.

When you open up an application, it may be installed on your local computer, or it may be installed on an application server somewhere on your LAN. When you create a data file on your workstation, like a Word document, you save it to your personal directory on a file server that is on your LAN.

Many years ago when computer systems were expensive, all the work was done on a mainframe, a huge computer surrounded by geeks in a special room. The end users had dumb terminals, meaning there was a keyboard and a monitor at your desk, but the box they attached to on your desk was called a dumb terminal because it did not do any work, it was dumb!

The concept of the workstation is that some of the "work" is done locally at your desktop, but some of the work could also be done on a computer somewhere else, in the case of the LAN, that somewhere else would be a server.

 

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The Data Link Layer of the OSI model

ComputerGuru -

The Data Link Layer is Layer 2 of the seven-layer OSI model of computer networking.  The Data Link layer deals with issues on a single segment of the network.

Layer two of the OSI model is one area where the difference between the theoretical OSI reference model and the implementation of TCP/IP with the competing Department of Defense (DoD) model. As we will discuss with the implementation of TCP/IP there is one lower layer called the network interface layer that encompasses Ethernet.

The IEEE 802 standards map to the lower two layers (Data Link and Physical) of the seven-layer OSI networking reference model. Even though we discussed many of these Ethernet terms in discussing the Physical Layer of the OSI model, we also discuss them here in the context of the Data Link Layer.

The IEEE 802 LAN/MAN Standards Committee develops Local Area Network standards and Metropolitan Area Network standards. In February 1980, the Institute of Electrical and Electronics Engineers (IEEE) started project 802 to standardize local area networks (LAN). IEEE 802 splits the OSI Data Link Layer into two sub-layers named Logical Link Control (LLC) and Media Access Control (MAC).

The lower sub-layer of the Data Link layer, the Media Access Control (MAC), performs Data Link layer functions related to the Physical layer, such as controlling access and encoding data into a valid signaling format.

The upper sub-layer of the Data Link layer, the Logical Link Control (LLC), performs Data Link layer functions related to the Network layer, such as providing and maintaining the link to the network.

The MAC and LLC sub-layers work in tandem to create a complete frame. The portion of the frame for which LLC is responsible is called a Protocol Data Unit (LLC PDU or PDU).

IEEE 802.2 defines the Logical Link Control (LLC) standard that performs functions in the upper portion of the Data Link layer, such as flow control and management of connection errors.

LLC supports the following three types of connections for transmitting data:
• Unacknowledged connectionless service:does not perform reliability checks or maintain a connection, very fast, most commonly used
• Connection oriented service. Once the connection is established, blocks of data can be transferred between nodes until one of the nodes terminates the connection.
• Acknowledged connectionless service provides a mechanism through which individual frames can be acknowledged

IEEE 802.3 is an extension of the original Ethernet. includes modifications to the classic Ethernet data packet structure.

The Media Access Control (MAC) sub-layer contains methods that logical topologies can use to regulate the timing of data signals and eliminate collisions.

The MAC address concerns a device's actual physical address, which is usually designated by the hardware manufacturer. Every device on the network must have a unique MAC address to ensure proper transmission and reception of data.  MAC communicates with adapter card.

Carrier Sense Multiple Access / Collision Detection is (CSMA/CD) a set of rules determining how network devices respond when two devices attempt to use a data channel simultaneously (called a collision). Standard Ethernet networks use CSMA/CD. This standard enables devices to detect a  collision.

After detecting a collision, a device waits a random delay time and then attempts to re-transmit the message. If the device detects a collision again, it waits twice as long to try to re-transmit the message. This is known as exponential back off.

IEEE 802.5 uses token passing to control access to the medium. IBM Token Ring is essentially a subset of IEEE 802.5.

The IEEE 802.11 specifications are wireless standards that specify an "over-the-air" interface between a wireless client and a base station or access point, as well as among wireless clients. The 802.11 standards can be compared to the IEEE 802.3™ standard for Ethernet for wired LANs. The IEEE 802.11 specifications address both the Physical (PHY) and Media Access Control (MAC) layers and are tailored to resolve compatibility issues between manufacturers of Wireless LAN equipment

The IEEE 802.15 Working Group provides, in the IEEE 802 family, standards for low-complexity and low-power consumption wireless connectivity.

IEEE 802.16 specifications support the development of fixed broadband wireless access systems to enable rapid worldwide deployment of innovative, cost-effective and interoperable multi-vendor broadband wireless access products.

A network interface controller (NIC), also known as a network interface card or network adapter, implements communications using a specific physical layer and data link layer standard such as Ethernet. The 1990s Ethernet network interface controller shown in the photo has a BNC connector (left) and an 8P8C connector (right).
 

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Physical Layer Topology in computer networking

ComputerGuru -

A network topology refers to the layout of the transmission medium and devices on a network. As a networking professional for many years I can honestly say about the only time network topology has come up is for certification testing. Here are some basic definitions.

Physical Topology:

Physical topology defines the cable's actual physical configuration (star, bus, mesh, ring, cellular, hybrid).

Bus: Uses a single main bus cable, sometimes called a backbone, to transmit data. Workstations and other network devices tap directly into the backbone by using drop cables that are connected to the backbone.  This topology is an old one and essentially has each of the computers on the network daisy-chained to each other. This type of network is usually peer to peer and uses Thinnet(10base2) cabling. It is configured by connecting a "T-connector" to the network adapter and then connecting cables to the T-connectors on the computers on the right and left. At both ends of the chain the network must be terminated with a 50 ohm impedance terminator.

Advantages: Cheap, simple to set up.
Disadvantages Excess network traffic, a failure may affect many users, Problems are difficult to troubleshoot.

Star: Branches out via drop cables from a central hub (also called a multiport repeater or concentrator) to each workstation. A signal is transmitted from a workstation up the drop cable to the hub. The hub then transmits the signal to other networked workstations.  The star is probably the most commonly used topology today. It uses twisted pair such as 10baseT or 100baseT cabling and requires that all devices are connected to a hub.

Advantages: centralized monitoring, failures do not affect others unless it is the hub, easy to modify.
Disadvantages If the hub fails then everything connected to it is down.

Ring: Connects workstations in a continuous loop. Workstations relay signals around the loop in round-robin fashion.  The ring topology looks the same as the star, except that it uses special hubs and ethernet adapters. The Ring topology is used with Token Ring networks, (a proprietary IBM System).

Advantages: Equal access.
Disadvantages Difficult to troubleshoot, network changes affect many users, failure affects many users.

Mesh: Provides each device with a point-to-point connection to every other device in the network.  Mesh topologies are combinations of the above and are common on very large networks. For example, a star bus network has hubs connected in a row(like a bus network) and has computers connected to each hub.

Cellular: Refers to a geographic area, divided into cells, combining a wireless structure with point-to-point and multipoint design for device attachment.

Logical Topology:

Logical topology defines the network path that a signal follows (ring or bus), regardless of its physical design.

Ring: Generates and sends the signal on a one-way path, usually counterclockwise.

Bus: Generates and sends the signal to all network devices.


LAN Media-Access Methods

Media contention occurs when two or more network devices have data to send at the same time. Because multiple devices cannot talk on the network simultaneously, some type of method must be used to allow one device access to the network media at a time. This is done in two main ways: carrier sense multiple access collision detect (CSMA/CD) and token passing.

In token-passing networks such as Token Ring and FDDI, a special network frame called a token is passed around the network from device to device.

For CSMA/CD networks, switches segment the network into multiple collision domains

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