Origin of internet pdf

President Dwight D. Their aim was to help American military technology stay ahead of its enemies and prevent surprises, such as the launch of the satellite Sputnik 1, happening again. Roberts was the first person to connect two computers. By , 30 academic, military and research institutions had joined the network, connecting locations including Hawaii, Norway and the UK.

The term is used to describe a set of protocols that govern how data moves through a network. After the creation of ARPANET, more networks of computers began to join the network, and the need arose for an agreed set of rules for handling data. The address on the datagram can be read by any computer, but only the final host machine can open the envelope and read the message inside. Kahn and Cerf called this method transmission-control protocol TCP. Every device connected to the internet is given a unique IP number.

Known as an IP address, the number can be used to find the location of any internet-connected device in the world. In the early s, cheaper technology and the appearance of desktop computers allowed the rapid development of local area networks LANs. An increase in the amount of computers on the network made it difficult to keep track of all the different IP addresses.

It was one of the innovations that paved the way for the World Wide Web. As the network increased in popularity and scope, users quickly realised the potential of the network as a tool for sending messages between different ARPANET computers. Ray Tomlinson , an American computer programmer, is responsible for electronic mail as we know it today. When DNS was introduced, this was extended to user host. Early email users sent personal messages and began mailing lists on specific topics.

The development of email showed how the network had transformed. Rather than a way of accessing expensive computing power, it had started to become a place to communicate, gossip and make friends.

From the s onwards, the home computer industry grew exponentially. Computers were embedded with the rhetoric of the future and learning, but in most cases this meant learning to program so that people could actually make the technology do something, such as play games.

Between and , the network grew from 2, hosts to 30, People were now using the internet to send messages to each other, read news and swap files. However, advanced knowledge of computing was still needed to dial in to the system and use it effectively, and there was still no agreement on the way that documents on the network were formatted.

People often turn to popular culture and humour to find answers to societal dilemmas Rushkoff 68 ; in the early s, the Internet meme is one of the ways people are addressing such issues.

Their nature and virality made Figure LOLCat reaction image mentioned by Zuckerman; 2. United States: the Binders Full of Internet memes a fitting genre to express Women meme - criticisng statements of Mitt opinions, encourage participation, and Romney; 3. Netherlands: a China19 fig. China: calling for the freedom of lawyer and civil rights activist Chen Guangcheng.

In such communities, general gossip, university rivalry, as well as discussions Figure Nijmegen Uni Memes. Nijmegen Uni Memes is only one of the numerous university meme pages that launched on Facebook, which show how Internet memes have become a part of vocabulary for Internet users. In , the Internet meme is undoubtedly one of the most widespread modes of online communication, and it is not only the emoticon any more.

This development also often serves as proof of the idea that the attention span of the younger generations is decreasing dangerously. Internet memes would not be this popular if users did not know how to read them.

They are making memes. Association for the Advancement of Artificial Intelligence, PDF file. Benner, Jeffrey. Berners-Lee, Tim. DeveloperWorks Podcasts.

IBM developerWorks, Biggs, John. Cassel, David. Computer Arts. Davison, Patrick. Michael Mandiberg. Dawkins, Richard. Dougherty, Beth K. Wiley Online Library. Fahlman, Scott E. Scott E. Fahlman's Homepage. Huhtamo, Erkki. Ignatio, Dino. Jenkins, Henry.

Blog post. Johnston, Rich. Knobel, Michele and Colin Lankshear. Cheezburger, Inc, Miltner, Kate. London School of Economics and Political Science, Murray, Susan. PDF File. Needler, Howard. Orange News. Rushkoff, Douglas.

London: Flamingo, Shifman, Limor and Mike Thelwall. Shirky, Clay. New York: The Penguin Press, User-created interactive timeline. Tourist of Death. Tourist of Death, Treharne, Elaine, ed.

Old and Middle English c. Malden [etc. Van de Fliert, Linda. Utrecht University, West, Angela. Wikipedia, the Free Encyclopedia. Wikimedia Foundation, Inc. They might not be able to use all the tools available on Internet. Leased Connection Leased connection is also known as direct Internet access or Level Three connection. It is the secure, dedicated and most expensive, level of Internet connection. With leased connection, your computer is dedicatedly and directly connected to the Internet using high-speed transmission lines.

It is on-line twenty-four hours a day, seven days a week. Leased Internet connections are limited to large corporations and universities who could afford the cost.

It is a dedicated phone connection supporting data rates of 1. A T-1 line actually consists of 24 individual channels, each of which supports 64Kbits per second. Most telephone companies allow you to buy just one or some of these individual channels. This is known as fractional T-1 access. Bonded T-1 A bonded T-1 is two or more T-1 lines that have been joined bonded together to increase bandwidth. Where a single T-1 provides approximately 1. Two bonded T-1s allow you to use the full bandwidth of 3Mbps where two individual T-1s can still only use a maximum of 1.

To be bonded the T-1 must run into the same router at the end, meaning they must run to the same ISP. T-3 Lines T-3 lines are dedicated phone connections supporting data rates of about 43 to 45 Mbps. It too is a popular leased line option. A T-3 line actually consists of individual channels, each of which supports 64 Kbps. DSL connects your home or office to the Internet through the same telephone wire that comes from the telephone pole on the street. DSL service, combines separate voice and data channels over a single telephone line.

In DSL, voice fills the low end of the frequency spectrum and data fills the high end. DSL is also relatively new technology that is just being introduced in many places. Hardware developers are working with service providers to make the service cost affordable for consumers. As time goes by, the service should become more widely available at a reasonable price.

Cable Connection Through the use of a cable modem you can have a broadband Internet connection that is designed to operate over cable TV lines. Cable Internet works by using TV channel space for data transmission, with certain channels used for downstream transmission, and other channels for upstream transmission.

Because the coaxial cable used by cable TV provides much greater bandwidth than telephone lines, a cable modem can be used to achieve extremely fast access. Cable lines offer an extremely high bandwidth connection to the Internet. It divides the connection into lots of bands, and translates the data in the bands into signals that can be carried through cable lines. Cable modems change these signals into IP packets that your computer can understand. To use cable modems you will need a cable splitter, a cable modem, and the service from a cable company.

Wireless Internet Connections Wireless Internet, or wireless broadband is one of the newest Internet connection types. Instead of using telephone or cable networks for your Internet connection, you use radio frequency bands. Wireless Internet provides an always-on connection which can be accessed from anywhere — as long as you geographically within a network coverage area.

Wireless access is still considered to be relatively new, and it may be difficult to find a wireless service provider in some areas. It is typically more expensive and mainly available in metropolitan areas. This provides connection to Internet through a dial-up terminal connection. The client computer uses modem to access a "host" and acts as if it is a terminal directly connected to that host.

And the host to which the client gets connected is actually connected to the Internet by a full time connection See Leased Connection. In dial-up connection to Internet, Host carries all the command that are typed on a client machine and forward them to Internet. Dial-up is an analog connection because data is sent over an analog, public telephone network. The modem converts received analog data to digital and vise versa.

Because dial-up access uses normal telephone lines the quality of the connection is not always good and data rates are limited. This type of connection can further be divided into three categories. This connection does not support Graphics display. However the user will be able to surf the Internet, do FTP, receive mail.

Shell Accounts were the only type of Internet access available for many years before the Internet entered in to the world of graphics and became more users friendly. Hence it is more popular Internet connection. Shell accounts are slowly phasing out from the Internet scenario.

ISDN Integrated services digital network ISDN is an international communications standard for sending voice, video, and data over digital telephone lines or normal telephone wires. ISDN is a dial-up service that has been provided by telephone companies for many years. This line combines two 64 Kbps channels to offer Kbps band width broken into three bands: one band for the ringing signal of your phone, one band for your telephone conversation, and one band for data.

Satellite Internet Satellite Internet is a form of high-speed Internet service. Satellite Internet services utilize telecommunications satellites in Earth orbit to provide Internet access to consumers. Internet over Satellite IoS allows a user to access the Internet via a satellite that orbits the earth.

A satellite is placed at a static point above the earth's surface, in a fixed position. Because of the enormous distances signals must travel from the earth up to the satellite and back again, IoS is slightly slower than high-speed terrestrial connections over copper or fiber optic cables. Satellite Internet service covers areas where DSL and cable access is unavailable.

Review Questions 1. State whether the following statements are True or False. Gateway Access is also known as Level-One connection. Leased connection is also known as direct Internet access or Level Three connection. Explain in brief the concept of e-mail.

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Previously published as: On the origin of species by means of natural selection 31 Copyright-evidence-date Copyright-evidence-operator lexw archive. That is, over many generations a species can evolve into something quite different, and those differences are based on changes in the DNA, which originate as mutations.

Yet we have many… How does this diversity arise from one ancestral form? And we should be able to find new species forming in the wild. Coyne devotes the remainder of his book to providing evidence for them. Fossils Coyne turns first to the fossil record. The deepest and oldest layers of rock would contain the fossils of more primitive species, and some fossils should become more complex as the layers of rock become younger, with organisms resembling present-day species found in the most recent layers.

In particular, he argued that Precambrian fossils had been destroyed by heat, pressure, and erosion. Since , however, paleontologists have discovered many Precambrian fossils, many of them microscopic or soft-bodied. These groups diversify over the next several million years, with terrestrial plants and tetrapods four-legged animals, the earliest of which were lobe-finned fish appearing about million years ago.

Living 48 million years ago, Indohyus was… probably very close to what the whale ancestor looked like. But if we go back 4 million more years, to 52 million years ago, we see what might well be that ancestor. It is a fossil skull from a wolf-sized creature called Pakicetus, which is bit more whalelike than Indohyus.

Coyne performs the same trick with fossils that are supposedly ancestral to modern birds. The textbook icon Archaeopteryx, with feathered wings like a modern bird but teeth and a tail like a reptile, is dated at million years. This is why the scientific literature typically shows each species branching off a supposed lineage.

In the figure below, all the lines are hypothetical. The diagram on the left is a representation of evolutionary theory: Species A is ancestral to B, which is ancestral to C, which is ancestral to D, which is ancestral to E. But the diagram on the right is a better representation of the evidence: Species A, B, C and D are not in the actual lineage leading to E, which remains unknown.

It turns out that no series of fossils can provide evidence for Darwinian descent with modification. Even in the case of living species, buried remains cannot generally be used to establish ancestor-descendant relationships.

Imagine finding two human skeletons in the same grave, one about thirty years older than the other. Was the older individual the parent of the younger? Without written genealogical records and identifying marks or in some cases DNA , it is impossible to answer the question.

And in this case we would be dealing with two skeletons from the same species that are only a generation apart and from the same location. With fossils from different species that are now extinct, and widely separated in time and space, there is no way to establish that one is the ancestor of another—no matter how many transitional fossils we find. In my possession are two little embryos in spirit, whose names I have omitted to attach, and at present I am quite unable to say to what class they belong.

They may be lizards or small birds, or very young mammals, so complete is the similarity in the mode of formation of the head and trunk in these animals. The passage Darwin cited was from a work written in German by von Baer in ; Thomas Henry Huxley translated it into English and published it in He called this The Biogenetic Law: Ontogeny recapitulates phylogeny.

It is best for things that evolved later to be programmed to develop later in the embryo. As one group evolves from another, it often adds its developmental program on top of the old one.

First, fossil embryos are extremely rare,20 so the reformulated law has to rely on embryos of modern organisms that are assumed to resemble ancestral forms. Theory first, observation later—just as von Baer had objected.