The Internet
The home of the 'A root server': the heart of the 'net
Bits of the Internet: DNS, FTP, WWW, Email, Search Engines etc
From 'How Stuff Works'
Warriors
of the Net - a beautiful animated metaphorical film on how the Internet
works.
Beware - it's a big download (78M, 114M or 148M).
The transcript of the film.
A Short History of the Internet
by Bruce Sterling (bruces@well.sf.ca.us ) (written in 1992)
Adapted from http://www.forthnet.gr/forthnet/isoc/short.history.of.internet
Literary Freeware -- Not for Commercial Use
Some thirty years ago, the RAND Corporation, America's foremost Cold War think-tank, faced a strange strategic problem. How could the US authorities successfully communicate after a nuclear war? Postnuclear America would need a command-and-control network, linked from city to city, state to state, base to base. But no matter how thoroughly that network was armored or protected, its switches and wiring would always be vulnerable to the impact of atomic bombs. A nuclear attack would reduce any conceivable network to tatters.
And how would the network itself be commanded and controlled? Any central authority, any network central citadel, would be an obvious and immediate target for an enemy missile. The center of the network would be the very first place to go. RAND mulled over this grim puzzle in deep military secrecy, and arrived at a daring solution. The RAND proposal (the brainchild of RAND staffer Paul Baran) was made public in 1964.
In the first place, the network would *have no central authority.*
Furthermore, it would be *designed from the beginning to operate while
in tatters.*
The principles were simple.
- The network itself would be assumed to be unreliable at all times.
- All the nodes in the network would be equal in status to all other nodes, each node with its own authority to originate, pass, and receive messages.
- The messages themselves would be divided into packets, each packet separately addressed.
- Each packet would begin at some specified source node, and end at some other specified destination node.
- Each packet would wind its way through the network on an individual basis.
- The particular route that the packet took would be unimportant. Only final results would count. Basically, the packet would be tossed like a hot potato from node to node to node, more or less in the direction of its destination, until it ended up in the proper place. If big pieces of the network had been blown away, that simply wouldn't matter; the packets would still stay airborne, lateralled wildly across the field by whatever nodes happened to survive. This rather haphazard delivery system might be "inefficient" in the usual sense (especially compared to, say, the telephone system) -- but it would be extremely rugged.
During the 60s, this intriguing concept of a decentralized, blastproof, packet-switching network was kicked around by RAND, MIT and UCLA. The National Physical Laboratory in Great Britain set up the first test network on these principles in 1968. Shortly afterward, the Pentagon's Advanced Research Projects Agency decided to fund a larger, more ambitious project in the USA.
The nodes of the network were to be high-speed supercomputers. These were rare and valuable machines which were in real need of good solid networking, for the sake of national research-and-development projects. In autumn 1969, the first such node was installed in UCLA. By December 1969, there were four nodes on the infant network, which was named ARPANET, after its Pentagon sponsor
[In 1957, while responding to the threat of the Soviets in general and the success of Sputnik (the first man-made satellite, launched by the USSR and terrifying to the Americans as a symbol of technological power) in particular, President Dwight Eisenhower created both the Interstate Highway System and the Advanced Research Projects Agency, or ARPA.]
The four computers could transfer data on dedicated high-speed transmission lines. They could even be programmed remotely from the other nodes. Thanks to ARPANET, scientists and researchers could share one another's computer facilities by long-distance. This was a very handy service, for computer-time was precious in the early '70s.
In 1971 there were fifteen nodes in ARPANET; by 1972, thirty-seven nodes.
In 1971 the Internet (ARPANET) looked like this:
And it was good. By the second year of operation, however, an odd fact became clear. ARPANET's users had warped the computer-sharing network into a dedicated, high-speed, federally subsidized electronic post- office. The main traffic on ARPANET was not long-distance computing. Instead, it was news and personal messages. Researchers were using ARPANET to collaborate on projects, to trade notes on work, and eventually, to downright gossip and schmooze. People had their own personal user accounts on the ARPANET computers, and their own personal addresses for electronic mail. Not only were they using ARPANET for person-to-person communication, but they were very enthusiastic about this particular service -- far more enthusiastic than they were about long-distance computation. It wasn't long before the invention of the mailing-list, an ARPANET broadcasting technique in which an identical message could be sent automatically to large numbers of network subscribers.
E-mail was invented by Ray Tomlinson of BBN in 1972. He picked the @ symbol from the available symbols on his teletype to link the username and address.
The telnet protocol, enabling logging on to a remote computer,
was published as a Request for Comments (RFC) in 1972. RFC's are a means
of sharing developmental work throughout community.
The FTP protocol, enabling file transfers between Internet nodes,
was published as an RFC in 1973.
The Unix to Unix Copy Protocol (UUCP) was invented in 1978 at Bell Labs. Usenet was started in 1979 based on UUCP. Newsgroups, which are discussion groups focusing on a topic, followed, providing a means of exchanging information throughout the world . While Usenet is not considered as part of the Internet, since it does not share the use of TCP/IP, it linked unix systems around the world, and many Internet sites took advantage of the availability of newsgroups. It was a significant part of the community building that took place on the networks.
Similarly, BITNET (Because It's Time Network) connected IBM mainframes around the educational community and the world to provide mail services beginning in 1981. Listserv software was developed for this network and later others. Gateways were developed to connect BITNET with the Internet and allowed exchange of e-mail, particularly for e-mail discussion lists. These listservs and other forms of e-mail discussion lists formed another major element in the community building that was taking place.
Archie: While the number of sites on the Internet was small, it was fairly easy to keep track of the resources of interest that were available. But as more and more universities and organizations--and their libraries-- connected, the Internet became harder and harder to track. There was more and more need for tools to index the resources that were available. The first effort, other than library catalogs, to index the Internet was created in 1989, as Peter Deutsch and his crew at McGill University in Montreal, created an archiver for ftp sites, which they named Archie. This software would periodically reach out to all known openly available ftp sites, list their files, and build a searchable index of the software.
Throughout the '70s, ARPA's network grew. Its decentralized structure made expansion easy. Unlike standard corporate computer networks, the ARPA network could accommodate many different kinds of machine. As long as individual machines could speak the packet-switching lingua franca [common language] of the new, anarchic network, their brand-names, and their content, and even their ownership, were irrelevant.
The ARPA's original standard for communication was known as NCP, "Network Control Protocol," but as time passed and the technique advanced, NCP was superceded by a higher-level, more sophisticated standard known as TCP/IP (first proposed by Bob Kahn at BBN). TCP, or "Transmission Control Protocol," converts messages into streams of packets at the source, then reassembles them back into messages at the destination. IP, or "Internet Protocol," handles the addressing, seeing to it that packets are routed across multiple nodes and even across multiple networks with multiple standards -- not only ARPA's pioneering NCP standard, but others like Ethernet.
As early as 1977, TCP/IP was being used by other networks to link to ARPANET. ARPANET itself remained fairly tightly controlled, at least until 1983, when its military segment broke off and became MILNET. But TCP/IP linked them all. And ARPANET itself, though it was growing, became a smaller and smaller neighborhood amid the vastly growing galaxy of other linked machines.
As the '70s and '80s advanced, many very different social groups found themselves in possession of powerful computers. It was fairly easy to link these computers to the growing network-of-networks. As the use of TCP/IP became more common, entire other networks fell into the digital embrace of the Internet, and messily adhered.
Since the software called TCP/IP was public-domain, and the basic technology was decentralized and rather anarchic by its very nature, it was difficult to stop people from barging in and linking up somewhere-or-other. In point of fact, nobody *wanted* to stop them from joining this branching complex of networks, which came to be known as the "Internet." Connecting to the Internet cost the taxpayer little or nothing, since each node was independent, and had to handle its own financing and its own technical requirements. The more, the merrier. Like the phone network, the computer network became steadily more valuable as it embraced larger and larger territories of people and resources.
A fax machine is only valuable if *everybody else* has a fax machine. Until they do, a fax machine is just a curiosity. ARPANET, too, was a curiosity for a while. Then computer-networking became an utter necessity. In 1984 the National Science Foundation got into the act, through its Office of Advanced Scientific Computing. The new NSFNET set a blistering pace for technical advancement, linking newer, faster, shinier supercomputers, through thicker, faster links, upgraded and expanded, again and again, in 1986, 1988, 1990. And other government agencies leapt in: NASA, the National Institutes of Health, the Department of Energy, each of them maintaining a digital satrapy [the territory under the control of a subordinate ruler] in the Internet confederation.
The nodes in this growing network-of-networks were divvied up into basic varieties. Foreign computers, and a few American ones, chose to be denoted by their geographical locations. The others were grouped by the six basic Internet "domains": gov, mil, edu, com, org and net. Gov, Mil, and Edu denoted governmental, military and educational institutions, which were, of course, the pioneers, since ARPANET had begun as a high-tech research exercise in national security. Com, however, stood for "commercial" institutions, which were soon bursting into the network like rodeo bulls, surrounded by a dust-cloud of eager nonprofit "orgs." (The "net" computers served as gateways between networks.)
ARPANET itself formally expired in 1989, a happy victim of its own overwhelming success. Its users scarcely noticed, for ARPANET's functions not only continued but steadily improved. The use of TCP/IP standards for computer networking is now global. In 1971, there were only four nodes in the ARPANET network. Today there are tens of thousands of nodes in the Internet, scattered over forty-two countries, with more coming on-line every day. Millions of people use this gigantic mother-of-all-computer-networks. The Internet is especially popular among scientists, and is probably the most important scientific instrument of the late twentieth century. The powerful, sophisticated access that it provides to specialized data and personal communication has sped up the pace of scientific research enormously.
Since the Internet was initially funded by the government, it was originally limited to research, education, and government uses. Commercial uses were prohibited unless they directly served the goals of research and education. This policy continued until the early 90's, when independent commercial networks began to grow. It then became possible to route traffic across the country from one commercial site to another without passing through the government funded NSFNet Internet backbone.
Delphi was the first national commercial online service to offer Internet access to its subscribers. It opened up an email connection in July 1992 and full Internet service in November 1992. All pretenses of limitations on commercial use disappeared in May 1995 when the National Science Foundation ended its sponsorship of the Internet backbone, and all traffic relied on commercial networks. AOL, Prodigy, and CompuServe came online. Since commercial usage was so widespread by this time and educational institutions had been paying their own way for some time, the loss of NSF funding had no appreciable effect on costs.
The Internet's pace of growth in the early 1990s is spectacular, almost ferocious. It is spreading faster than cellular phones, faster than fax machines. Last year the Internet was growing at a rate of twenty percent a *month.* The number of "host" machines with direct connection to TCP/IP has been doubling every year since 1988. The Internet is moving out of its original base in military and research institutions, into elementary and high schools, as well as into public libraries and the commercial sector.
Gopher: In 1991, the first really friendly interface to the Internet was developed at the University of Minnesota. The University wanted to develop a simple menu system to access files and information on campus through their local network. The demonstration system was called a gopher after the U of Minnesota mascot--the golden gopher. The gopher proved to be very prolific, and within a few years there were over 10,000 gophers around the world. It takes no knowledge of unix or computer architecture to use. In a gopher system, you type or click on a number to select the menu selection you want.
Why do people want to be "on the Internet?" One of the main reasons is simple freedom. The Internet is a rare example of a true, modern, functional anarchy. There is no "Internet Inc." There are no official censors, no bosses, no board of directors, no stockholders. In principle, any node can speak as a peer to any other node, as long as it obeys the rules of the TCP/IP protocols, which are strictly technical, not social or political.
The headless, anarchic, million-limbed Internet is spreading like bread-mold. Any computer of sufficient power is a potential spore for the Internet, and today such computers sell for less than $2,000 and are in the hands of people all over the world. ARPA's network, designed to assure control of a ravaged society after a nuclear holocaust, has been superceded by its mutant child the Internet, which is thoroughly out of control, and spreading exponentially through the post-Cold War electronic global village. The spread of the Internet in the 90s resembles the spread of personal computing in the 1970s, though it is even faster and perhaps more important. More important, perhaps, because it may give those personal computers a means of cheap, easy storage and access that is truly planetary in scale.
And this was written before the WWW was properly developed!
WWW: In 1989 another significant event took place in making the nets easier to use. Tim Berners-Lee and others at the European Laboratory for Particle Physics (CERN), proposed a new protocol for information distribution. This protocol, which became the World Wide Web in 1991, was based on hypertext--a system of embedding links in text to link to other text, which you have been using every time you selected a text link while reading these pages. Although started before gopher, it was slower to develop.
The development in 1993 of the graphical browser Mosaic by Marc Andreessen and his team at the National Center For Supercomputing Applications (NCSA) gave the protocol its big boost. Later, Andreessen moved to become the brains behind Netscape Corp., which produced the most successful graphical type of browser and server until Microsoft declared war and developed its Microsoft Internet Explorer.
Michael Dertouzos of MIT's Laboratory for Computer Sciences persuaded Tim Berners-Lee and others to form the World Wide Web Consortium (W3C) in 1994 to promote and develop standards for the Web. Proprietary plug-ins still abound for the web, but the Consortium has ensured that there are common standards present in every browser.
The World Wide Web was named by Tim Berners-Lee, who created the first web browser and invented HTTP. As he was thinking of a name, he says: "Alternatives I considered were "Mine of information" ("Moi", c'est un peu egoiste) and "The Information Mine ("Tim", even more egocentric!), and "Information Mesh"
For many people today, the World Wide Web is the Internet.
Microsoft's full scale entry into the browser, server, and Internet Service Provider market completed the major shift over to a commercially based Internet. The release of Windows 98 in June 1998 with the Microsoft browser well integrated into the desktop shows Bill Gates' determination to capitalize on the enormous growth of the Internet. Microsoft's success over the past few years has brought court challenges to their dominance. We'll leave it up to you whether you think these battles should be played out in the courts or the marketplace.
A current trend with major implications for the future is the growth of high speed connections. 56K modems and the providers who support them are spreading widely, but this is just a small step compared to what will follow. 56K is not fast enough to carry multimedia, such as sound and video except in low quality. But new technologies many times faster, such as cablemodems, digital subscriber lines (DSL ), and satellite broadcast are available in limited locations now, and will become widely available in the next few years. These technologies present problems, not just in the user's connection, but in maintaining high speed data flow reliably from source to the user. Those problems are being worked on, too.
During this period of enormous growth, businesses entering the Internet arena scrambled to find economic models that work. Free services supported by advertising shifted some of the direct costs away from the consumer--temporarily. Services such as Delphi offered free web pages, chat rooms, and message boards for community building. Online sales have grown rapidly for such products as books and music CDs and computers, but the profit margins are slim when price comparisons are so easy, and public trust in online security is still shaky. Business models that have worked well are portal sites, that try to provide everything for everybody, and live auctions. AOL's acquisition of Time-Warner was the largest merger in history when it took place and shows the enormous growth of Internet business! The stock market has had a rocky ride, swooping up and down as the new technology companies, the dot.com's encountered good news and bad. The decline in advertising income spelled doom for many dot.coms, and a major shakeout and search for better business models is underway by the survivors.
It is becoming more and more clear that many free services will not survive. While many users still expect a free ride, there are fewer and fewer providers who can find a way to provide it. The value of the Internet and the Web is undeniable, but there is a lot of shaking out to do and management of costs and expectations before it can regain its rapid growth. May you live in interesting times! (ostensibly an ancient Chinese curse)
The first Internet message
From http://www.netvalley.com/intval.html
On Oct 29, 1969, BBN delivered an Interface Message Processor (IMP) to UCLA that was based on a Honeywell DDP 516, and when they turned it on, it just started running. It was hooked by 50 Kbps circuits to two other sites (SRI and UCSB) in the four-node network: UCLA, Stanford Research Institute (SRI), UC Santa Barbara (UCSB), and the University of Utah in Salt Lake City.
The plan was unprecedented: Kleinrock, a pioneering computer science professor at UCLA, and his small group of graduate students hoped to log onto the Stanford computer and try to send it some data.They would start by typing "login," and seeing if the letters appeared on the far-off monitor.
We set up a telephone connection between us and the guys at SRI, Kleinrock
said in an interview.
We typed the L and we asked on the phone, "Do you see the L?"
"Yes, we see the L," came the response.
"We typed the O, and we asked, "Do you see the O?"
"Yes, we see the O."
Then we typed the G, and the system crashed...
Things have not changed too much since then!
The heart of the Internet
'Most people envision the Internet as a global network that resides on no single physical system or network of systems. While that picture is roughly correct, key pieces of the Internet's technological backbone are concentrated in a handful of physical locations around the world.'
From http://www.washingtonpost.com/wp-dyn/articles/A33447-2002Mar28.html
By David McGuire Newsbytes Friday, March 29, 2002; Page E05
Squatting unobtrusively on the banks of a man-made pond in an unremarkable corporate subdivision a few miles outside the Beltway, the home of the Internet's authoritative root server and master registry of dot-com addresses is virtually indistinguishable from the other red-brick office buildings that surround it. Despite its humdrum facade, VeriSign's Network Operations Center (NOC) is one of the most important physical locations in the virtual world.
Obscurity is the first line of defense. The building is unmarked, its address unspecified in company literature and its managers tight-lipped about disclosing driving directions or identifying markings to strangers. Visitors start with a stroll through a metal detector and past a guard desk, much as they would in any moderately secure office building. They take an elevator to the top floor, where security is tightest and inconspicuous cameras monitor the hallways. The few entrances to the operations center and server rooms can only be reached through antechambers called "mantraps" which are outfitted with scanners that read the unique contours of visitors' palms. If an unauthorized visitor places his hand in the scanner it triggers a lockdown, sealing the intruder in one of the narrow, wood-paneled closets until security forces arrive to remove them.
Adjoining the operations center, behind another mantrap, are twin rooms that house the essential computers that serve as the heart of the Net. Here, hundreds of whirring computer fans and an industrial-strength air conditioner drown out anything quieter than a close-range shout. Black, seven-foot-tall computer server towers are aligned in rows that stretch nearly the length of the room. The white floor is slotted to allow airflow and a steady, conditioned breeze streams up from below, making all metal surfaces in the room cool to the touch. Small dome-like security cameras, similar to those used in casinos, pock the white ceiling, evenly spaced between chemical fire suppression devices. There isn't a cranny of the server area where a person could hide from surveillance.
Between the server hedgerows are several equally tall storage units, where the continually updated master lists of the addresses registered in dot-com, dot-net and dot-org are stored. And tucked away in a less-traveled back corner of one of the server rooms, behind the door of a black tower that looks no different than any of the others, is the principal reason for all the precautions: the A root server.
Most people envision the Internet as a global network that resides on no single physical system or network of systems. While that picture is roughly correct, key pieces of the Internet's technological backbone are concentrated in a handful of physical locations around the world.
The Domain Name System (DNS) makes the Web easy to navigate by translating long Internet protocol (IP) numbers into memorable Web and e-mail addresses. It relies on a hierarchy of physical root servers to inform computers connected to the Internet where they need to look to find specific locations online.
At the top of that hierarchy is the A root server, which every 12 hours generates a "zone" file, which in turn tells a dozen other root servers spread around the world what Internet domains exist and where they can be found.
One rung below the root servers in the Internet hierarchy are the servers that house Internet domains such as dot-com, dot-biz and dot-info. Three of the largest and most widely used of those domains -- dot-com, dot-org and dot-net -- are run alongside the A root server at the Network Operations Center.
VeriSign manages the A root server and dot-com registry under contracts with the Commerce Department and global Internet addressing authorities.
But despite the precautions that go into protecting the assets in the facility, Rippe said the Internet would not be irreparably harmed if the building were to vaporize tomorrow. "The last thing I'd want someone to think is that they could put a bomb around their waist and hug the A root and think they're going to significantly impact the Internet," Rippe said. The Internet's addressing system is designed to withstand the destruction of much of the physical infrastructure that houses it.
The DNS is built so that eight or more of the world's 13 master root servers would have to fail before ordinary Internet users started to see slowdowns.
A virtual map of part of the Internet: cyberspace will
soon be here.
Story location: http://www.wired.com/news/infostructure/0,1377,57013,00.html
02:00 AM Dec. 31, 2002 PT
From its early days as a pet project in the Department of Defense to its infamous time nestled under Al Gore's wing, the history of the Internet is littered with dozens of so-called birthdays.
But, as Gore can surely attest, not everyone agrees when they are.
Wednesday (January 1, 2003) is one of those days.
Some historians claim the Internet was born in 1961, when Dr. Leonard Kleinrock first published a paper on packet-switching technology at MIT.
Others cite 1969, when the Department of Defense commissioned the Advanced Research Projects Agency Network, known as ARPANET, to research a communication and command network that could withstand a nuclear attack.
The 1970s boast a slew of what could be pegged essential Internet milestones, including the advent of e-mail and the splintering off of ARPANET from military experiment to public resource.
But perhaps the most famous of the lot is the acclaimed Jan. 1, 1983, switch from Network Control Protocol to Transmission Control Protocol and Internet Protocol.
The transition from NCP to TCP/IP may not have been the sexiest moment in Internet history, but it was a key transition that paved the way for today's Internet.
Call it one small switch for man, but one giant switch for mankind.com.
Protocols are communication standards that allow computers to speak to one another over a network. Just as English speakers of different dialects and accents can often understand one another, protocols provide a lingua franca for all the different kinds of computers that hook into the Internet.
Until that fateful moment 20 years ago, the fewer than 1,000 computers that connected to ARPANET used the primitive Network Control Protocol, which was useful for the small community despite some limitations.
"NCP was sufficient to allow some Internetting to take place," said Kleinrock, now a computer science professor at UCLA. "It was not an elegant solution, but it was a sufficient solution.
"They saw a more general approach was needed."
Indeed, as ARPANET continued its exponential growth into the 1980s, the project's administrators realized they would need a new protocol to accommodate the much larger and more complicated network they foresaw as the Internet's future.
Vint Cerf, who is credited with co-designing the TCP/IP protocol with Robert Kahn, said, "It was designed to be future-proof and to run on any communication system."
The switch was "tremendously important," according to Rhonda Hauben, co-author of Netizens: On the History and Impact of Usenet and the Internet.
"It was critical because there was an understanding that the Internet would be made up of lots of different networks," Hauben said. "Somehow the Internet infrastructure had to be managed in a way to accommodate a variety of entities."
But despite the need to take ARPANET to the next level, the decision to switch to TCP/IP was controversial.
Like the current Windows versus Linux debate, there were factions of the community that wanted to adopt different standards, most notably the Open Systems Interconnection protocol.
"A lot of people in the community -- even though we had given them six months' to a year's notice -- they didn't really take it seriously," Kahn said.
"We had to jam it down their throats," Cerf said.
It was worth the jamming, Hauben said.
"They had the vision," she said. "They understood that this was going to be something substantial, and that's what they provided for in a very special way."