Premier IT Outsourcing and Support Services within the UK

User Tools

Site Tools


Network Working Group E. Krol Request for Comments: 1462 University of Illinois FYI: 20 E. Hoffman

                                                 Merit Network, Inc.
                                                            May 1993
                   FYI on "What is the Internet?"

Status of this Memo

 This memo provides information for the Internet community.  It does
 not specify an Internet standard.  Distribution of this memo is


 This FYI RFC answers the question, "What is the Internet?" and is
 produced by the User Services Working Group of the Internet
 Engineering Task Force (IETF). Containing a modified chapter from Ed
 Krol's 1992 book, "The Whole Internet User's Guide and Catalog," the
 paper covers the Internet's definition, history, administration,
 protocols, financing, and current issues such as growth,
 commercialization, and privatization.


 A commonly asked question is "What is the Internet?" The reason such
 a question gets asked so often is because there's no agreed upon
 answer that neatly sums up the Internet. The Internet can be thought
 about in relation to its common protocols, as a physical collection
 of routers and circuits, as a set of shared resources, or even as an
 attitude about interconnecting and intercommunication. Some common
 definitions given in the past include:
  • a network of networks based on the TCP/IP protocols,
  • a community of people who use and develop those networks,
  • a collection of resources that can be reached from those


 Today's Internet is a global resource connecting millions of users
 that began as an experiment over 20 years ago by the U.S.  Department
 of Defense. While the networks that make up the Internet are based on
 a standard set of protocols (a mutually agreed upon method of
 communication between parties), the Internet also has gateways to
 networks and services that are based on other protocols.

Krol & Hoffman [Page 1] RFC 1462 What is the Internet? May 1993

 To help answer the question more completely, the rest of this paper
 contains an updated second chapter from "The Whole Internet User's
 Guide and Catalog" by Ed Krol (1992) that gives a more thorough
 explanation. (The excerpt is published through the gracious
 permission of the publisher, O'Reilly & Associates, Inc.)

The Internet (excerpt from "The Whole Internet User's Guide and Catalog")

 The Internet was born about 20 years ago, trying to connect together
 a U.S. Defense Department network called the ARPAnet and various
 other radio and satellite networks. The ARPAnet was an experimental
 network designed to support military research--in particular,
 research about how to build networks that could withstand partial
 outages (like bomb attacks) and still function.  (Think about this
 when I describe how the network works; it may give you some insight
 into the design of the Internet.) In the ARPAnet model, communication
 always occurs between a source and a destination computer. The
 network itself is assumed to be unreliable; any portion of the
 network could disappear at any moment (pick your favorite
 catastrophe--these days backhoes cutting cables are more of a threat
 than bombs). It was designed to require the minimum of information
 from the computer clients. To send a message on the network, a
 computer only had to put its data in an envelope, called an Internet
 Protocol (IP) packet, and "address" the packets correctly. The
 communicating computers--not the network itself--were also given the
 responsibility to ensure that the communication was accomplished. The
 philosophy was that every computer on the network could talk, as a
 peer, with any other computer.
 These decisions may sound odd, like the assumption of an "unreliable"
 network, but history has proven that most of them were reasonably
 correct. Although the Organization for International Standardization
 (ISO) was spending years designing the ultimate standard for computer
 networking, people could not wait. Internet developers in the US, UK
 and Scandinavia, responding to market pressures, began to put their
 IP software on every conceivable type of computer. It became the only
 practical method for computers from different manufacturers to
 communicate. This was attractive to the government and universities,
 which didn't have policies saying that all computers must be bought
 from the same vendor. Everyone bought whichever computer they liked,
 and expected the computers to work together over the network.
 At about the same time as the Internet was coming into being,
 Ethernet local area networks ("LANs") were developed. This technology
 matured quietly, until desktop workstations became available around
 1983. Most of these workstations came with Berkeley UNIX, which
 included IP networking software. This created a new demand: rather

Krol & Hoffman [Page 2] RFC 1462 What is the Internet? May 1993

 than connecting to a single large timesharing computer per site,
 organizations wanted to connect the ARPAnet to their entire local
 network. This would allow all the computers on that LAN to access
 ARPAnet facilities. About the same time, other organizations started
 building their own networks using the same communications protocols
 as the ARPAnet: namely, IP and its relatives. It became obvious that
 if these networks could talk together, users on one network could
 communicate with those on another; everyone would benefit.
 One of the most important of these newer networks was the NSFNET,
 commissioned by the National Science Foundation (NSF), an agency of
 the U.S. government. In the late 80's the NSF created five
 supercomputer centers. Up to this point, the world's fastest
 computers had only been available to weapons developers and a few
 researchers from very large corporations. By creating supercomputer
 centers, the NSF was making these resources available for any
 scholarly research. Only five centers were created because they were
 so expensive--so they had to be shared. This created a communications
 problem: they needed a way to connect their centers together and to
 allow the clients of these centers to access them.  At first, the NSF
 tried to use the ARPAnet for communications, but this strategy failed
 because of bureaucracy and staffing problems.
 In response, NSF decided to build its own network, based on the
 ARPAnet's IP technology. It connected the centers with 56,000 bit per
 second (56k bps) telephone lines.  (This is roughly the ability to
 transfer two full typewritten pages per second.  That's slow by
 modern standards, but was reasonably fast in the mid 80's.)  It was
 obvious, however, that if they tried to connect every university
 directly to a supercomputing center, they would go broke. You pay for
 these telephone lines by the mile. One line per campus with a
 supercomputing center at the hub, like spokes on a bike wheel, adds
 up to lots of miles of phone lines. Therefore, they decided to create
 regional networks. In each area of the country, schools would be
 connected to their nearest neighbor. Each chain was connected to a
 supercomputer center at one point and the centers were connected
 together. With this configuration, any computer could eventually
 communicate with any other by forwarding the conversation through its
 This solution was successful--and, like any successful solution, a
 time came when it no longer worked. Sharing supercomputers also
 allowed the connected sites to share a lot of other things not
 related to the centers. Suddenly these schools had a world of data
 and collaborators at their fingertips. The network's traffic
 increased until, eventually, the computers controlling the network
 and the telephone lines connecting them were overloaded. In 1987, a
 contract to manage and upgrade the network was awarded to Merit

Krol & Hoffman [Page 3] RFC 1462 What is the Internet? May 1993

 Network Inc., which ran Michigan's educational network, in
 partnership with IBM and MCI. The old network was replaced with
 faster telephone lines (by a factor of 20), with faster computers to
 control it.
 The process of running out of horsepower and getting bigger engines
 and better roads continues to this day. Unlike changes to the highway
 system, however, most of these changes aren't noticed by the people
 trying to use the Internet to do real work. You won't go to your
 office, log in to your computer, and find a message saying that the
 Internet will be inaccessible for the next six months because of
 improvements. Perhaps even more important: the process of running out
 of capacity and improving the network has created a technology that's
 extremely mature and practical. The ideas have been tested; problems
 have appeared, and problems have been solved.
 For our purposes, the most important aspect of the NSF's networking
 effort is that it allowed everyone to access the network. Up to that
 point, Internet access had been available only to researchers in
 computer science, government employees, and government contractors.
 The NSF promoted universal educational access by funding campus
 connections only if the campus had a plan to spread the access
 around. So everyone attending a four year college could become an
 Internet user.
 The demand keeps growing. Now that most four-year colleges are
 connected, people are trying to get secondary and primary schools
 connected. People who have graduated from college know what the
 Internet is good for, and talk their employers into connecting
 corporations. All this activity points to continued growth,
 networking problems to solve, evolving technologies, and job security
 for networkers.

What Makes Up the Internet?

 What comprises the Internet is a difficult question; the answer
 changes over time. Five years ago the answer would have been easy:
 "All the networks, using the IP protocol, which cooperate to form a
 seamless network for their collective users." This would include
 various federal networks, a set of regional networks, campus
 networks, and some foreign networks.
 More recently, some non-IP-based networks saw that the Internet was
 good. They wanted to provide its services to their clientele. So they
 developed methods of connecting these "strange" networks (e.g.,
 Bitnet, DECnets, etc.) to the Internet. At first these connections,
 called "gateways", merely served to transfer electronic mail between
 the two networks. Some, however, have grown to translate other

Krol & Hoffman [Page 4] RFC 1462 What is the Internet? May 1993

 services between the networks as well. Are they part of the Internet?
 Maybe yes and maybe no. It depends on whether, in their hearts, they
 want to be. If this sounds strange, read on--it gets stranger.

Who Governs the Internet?

 In many ways the Internet is like a church: it has its council of
 elders, every member has an opinion about how things should work, and
 you can either take part or not. It's your choice. The Internet has
 no president, chief operating officer, or Pope. The constituent
 networks may have presidents and CEO's, but that's a different issue;
 there's no single authority figure for the Internet as a whole.
 The ultimate authority for where the Internet is going rests with the
 Internet Society, or ISOC. ISOC is a voluntary membership
 organization whose purpose is to promote global information exchange
 through Internet technology.  (If you'd like more information, or if
 you would like to join, contact information is provided in the "For
 More Information" section, near the end of this document.)  It
 appoints a council of elders, which has responsibility for the
 technical management and direction of the Internet.
 The council of elders is a group of invited volunteers called the
 Internet Architecture Board, or the IAB. The IAB meets regularly to
 "bless" standards and allocate resources, like addresses. The
 Internet works because there are standard ways for computers and
 software applications to talk to each other. This allows computers
 from different vendors to communicate without problems. It's not an
 IBM-only or Sun-only or Macintosh-only network. The IAB is
 responsible for these standards; it decides when a standard is
 necessary, and what the standard should be. When a standard is
 required, it considers the problem, adopts a standard, and announces
 it via the network. (You were expecting stone tablets?) The IAB also
 keeps track of various numbers (and other things) that must remain
 unique. For example, each computer on the Internet has a unique 32-
 bit address; no other computer has the same address.  How does this
 address get assigned? The IAB worries about these kinds of problems.
 It doesn't actually assign the addresses, but it makes the rules
 about how to assign addresses.
 As in a church, everyone has opinions about how things ought to run.
 Internet users express their opinions through meetings of the
 Internet Engineering Task Force (IETF). The IETF is another volunteer
 organization; it meets regularly to discuss operational and near-term
 technical problems of the Internet. When it considers a problem
 important enough to merit concern, the IETF sets up a "working group"
 for further investigation. (In practice, "important enough" usually
 means that there are enough people to volunteer for the working

Krol & Hoffman [Page 5] RFC 1462 What is the Internet? May 1993

 group.) Anyone can attend IETF meetings and be on working groups; the
 important thing is that they work. Working groups have many different
 functions, ranging from producing documentation, to deciding how
 networks should cooperate when problems occur, to changing the
 meaning of the bits in some kind of packet. A working group usually
 produces a report. Depending on the kind of recommendation, it could
 just be documentation and made available to anyone wanting it, it
 could be accepted voluntarily as a good idea which people follow, or
 it could be sent to the IAB to be declared a standard.
 If you go to a church and accept its teachings and philosophy, you
 are accepted by it, and receive the benefits. If you don't like it,
 you can leave. The church is still there, and you get none of the
 benefits. Such is the Internet. If a network accepts the teachings of
 the Internet, is connected to it, and considers itself part of it,
 then it is part of the Internet. It will find things it doesn't like
 and can address those concerns through the IETF. Some concerns may be
 considered valid and the Internet may change accordingly.  Some of
 the changes may run counter to the religion, and be rejected. If the
 network does something that causes damage to the Internet, it could
 be excommunicated until it mends its evil ways.

Who Pays for It?

 The old rule for when things are confusing is "follow the money."
 Well, this won't help you to understand the Internet. No one pays for
 "it"; there is no Internet, Inc. that collects fees from all Internet
 networks or users. Instead, everyone pays for their part.  The NSF
 pays for NSFNET. NASA pays for the NASA Science Internet.  Networks
 get together and decide how to connect themselves together and fund
 these interconnections. A college or corporation pays for their
 connection to some regional network, which in turn pays a national
 provider for its access.

What Does This Mean for Me?

 The concept that the Internet is not a network, but a collection of
 networks, means little to the end user. You want to do something
 useful: run a program, or access some unique data. You shouldn't have
 to worry about how it's all stuck together. Consider the telephone
 system--it's an internet, too. Pacific Bell, AT&T, MCI, British
 Telephony, Telefonos de Mexico, and so on, are all separate
 corporations that run pieces of the telephone system. They worry
 about how to make it all work together; all you have to do is dial.
 If you ignore cost and commercials, you shouldn't care if you are
 dealing with MCI, AT&T, or Sprint. Dial the number and it works.

Krol & Hoffman [Page 6] RFC 1462 What is the Internet? May 1993

 You only care who carries your calls when a problem occurs. If
 something goes out of service, only one of those companies can fix
 it. They talk to each other about problems, but each phone carrier is
 responsible for fixing problems on its own part of the system.  The
 same is true on the Internet. Each network has its own network
 operations center (NOC). The operation centers talk to each other and
 know how to resolve problems. Your site has a contract with one of
 the Internet's constituent networks, and its job is to keep your site
 happy. So if something goes wrong, they are the ones to gripe at. If
 it's not their problem, they'll pass it along.

What Does the Future Hold?

 Finally, a question I can answer. It's not that I have a crystal ball
 (if I did I'd spend my time on Wall Street instead of writing a
 book). Rather, these are the things that the IAB and the IETF discuss
 at their meetings. Most people don't care about the long discussions;
 they only want to know how they'll be affected. So, here are
 highlights of the networking future.

New Standard Protocols

 When I was talking about how the Internet started, I mentioned the
 International Standards Organization (ISO) and their set of protocol
 standards. Well, they finally finished designing it. Now it is an
 international standard, typically referred to as the ISO/OSI (Open
 Systems Interconnect) protocol suite. Many of the Internet's
 component networks allow use of OSI today. There isn't much demand,
 yet. The U.S. government has taken a position that government
 computers should be able to speak these protocols. Many have the
 software, but few are using it now.
 It's really unclear how much demand there will be for OSI,
 notwithstanding the government backing. Many people feel that the
 current approach isn't broke, so why fix it? They are just becoming
 comfortable with what they have, why should they have to learn a new
 set of commands and terminology just because it is the standard?
 Currently there are no real advantages to moving to OSI. It is more
 complex and less mature than IP, and hence doesn't work as
 efficiently. OSI does offer hope of some additional features, but it
 also suffers from some of the same problems which will plague IP as
 the network gets much bigger and faster. It's clear that some sites
 will convert to the OSI protocols over the next few years.  The
 question is: how many?

Krol & Hoffman [Page 7] RFC 1462 What is the Internet? May 1993

International Connections

 The Internet has been an international network for a long time, but
 it only extended to the United States' allies and overseas military
 bases. Now, with the less paranoid world environment, the Internet is
 spreading everywhere. It's currently in over 50 countries, and the
 number is rapidly increasing. Eastern European countries longing for
 western scientific ties have wanted to participate for a long time,
 but were excluded by government regulation. This ban has been
 relaxed. Third world countries that formerly didn't have the means to
 participate now view the Internet as a way to raise their education
 and technology levels.
 In Europe, the development of the Internet used to be hampered by
 national policies mandating OSI protocols, regarding IP as a cultural
 threat akin to EuroDisney.  These policies prevented development of
 large scale Internet infrastructures except for the Scandinavian
 countries which embraced the Internet protocols long ago and are
 already well-connected.  In 1989, RIPE (Reseaux IP Europeens) began
 coordinating the operation of the Internet in Europe and presently
 about 25% of all hosts connected to the Internet are located in
 At present, the Internet's international expansion is hampered by the
 lack of a good supporting infrastructure, namely a decent telephone
 system. In both Eastern Europe and the third world, a state-of-the-
 art phone system is nonexistent. Even in major cities, connections
 are limited to the speeds available to the average home anywhere in
 the U.S., 9600 bits/second. Typically, even if one of these countries
 is "on the Internet," only a few sites are accessible. Usually, this
 is the major technical university for that country. However, as phone
 systems improve, you can expect this to change too; more and more,
 you'll see smaller sites (even individual home systems) connecting to
 the Internet.


 Many big corporations have been on the Internet for years. For the
 most part, their participation has been limited to their research and
 engineering departments. The same corporations used some other
 network (usually a private network) for their business
 communications. After all, this IP stuff was only an academic toy.
 The IBM mainframes that handled their commercial data processing did
 the "real" networking using a protocol suite called System Network
 Architecture (SNA).
 Businesses are now discovering that running multiple networks is
 expensive. Some are beginning to look to the Internet for "one-stop"

Krol & Hoffman [Page 8] RFC 1462 What is the Internet? May 1993

 network shopping. They were scared away in the past by policies which
 excluded or restricted commercial use. Many of these policies are
 under review and will change. As these restrictions drop, commercial
 use of the Internet will become progressively more common.
 This should be especially good for small businesses. Motorola or
 Standard Oil can afford to run nationwide networks connecting their
 sites, but Ace Custom Software couldn't. If Ace has a San Jose office
 and a Washington office, all it needs is an Internet connection on
 each end. For all practical purposes, they have a nationwide
 corporate network, just like the big boys.


 Right behind commercialization comes privatization. For years, the
 networking community has wanted the telephone companies and other
 for-profit ventures to provide "off the shelf" IP connections.  That
 is, just like you can place an order for a telephone jack in your
 house for your telephone, you could do this for an Internet
 connection. You order, the telephone installer leaves, and you plug
 your computer into the Internet. Except for Bolt, Beranek and Newman,
 the company that ran the ARPAnet, there weren't any takers.  The
 telephone companies have historically said, "We'll sell you phone
 lines, and you can do whatever you like with them." By default, the
 Federal government stayed in the networking business.
 Now that large corporations have become interested in the Internet,
 the phone companies have started to change their attitude. Now they
 and other profit-oriented network purveyors complain that the
 government ought to get out of the network business. After all, who
 best can provide network services but the "phone companies"?  They've
 got the ear of a lot of political people, to whom it appears to be a
 reasonable thing. If you talk to phone company personnel, many of
 them still don't really understand what the Internet is about. They
 ain't got religion, but they are studying the Bible furiously.
 (Apologies to those telephone company employees who saw the light
 years ago and have been trying to drag their employers into church.)
 Although most people in the networking community think that
 privatization is a good idea, there are some obstacles in the way.
 Most revolve around the funding for the connections that are already
 in place. Many schools are connected because the government pays part
 of the bill. If they had to pay their own way, some schools would
 probably decide to spend their money elsewhere. Major research
 institutions would certainly stay on the net; but some smaller
 colleges might not, and the costs would probably be prohibitive for
 most secondary schools (let alone grade schools).  What if the school
 could afford either an Internet connection or a science lab? It's

Krol & Hoffman [Page 9] RFC 1462 What is the Internet? May 1993

 unclear which one would get funded. The Internet has not yet become a
 "necessity" in many people's minds. When it does, expect
 privatization to come quickly.
 Well, enough questions about the history of the information highway
 system. It's time to walk to the edge of the road, try and hitch a
 ride, and be on your way.


 We would like to thank O'Reilly & Associates for permission to
 reprint the chapter from their book by Ed Krol (1992), "The Whole
 Internet User's Guide and Catalog."

For More Information

 Hoffman, E. and L. Jackson. (1993) "FYI on Introducing the Internet
 --A Short Bibliography of Introductory Internetworking Readings for
 the Network Novice," 4 p.  (FYI 19, RFC 1463).
    To find out how to obtain this document and other on-line
    introductory readings, send an e-mail message to:, with the following text:
 Krol, Ed. (1992) The Whole Internet User's Guide and Catalog,
 O'Reilly & Associates, Sebastopol, CA. ISBN 1-56592-025-2.
 Quarterman, J. (1993) "Recent Internet Books," 15 p. (RFC 1432).
 The Internet Society
 Phone: (703) 620-8990
 Fax: (703) 620-0913

Krol & Hoffman [Page 10] RFC 1462 What is the Internet? May 1993

Security Considerations

 Security issues are not discussed in this memo.

Authors' Addresses

 Ed Krol
 Computing and Communications Service Office
 Univ. of Illinois Urbana Champaign (UIUC)
 1304 W Springfield
 Urbana, IL 61801
 Phone: (217)333-7886
 Ellen Hoffman
 Merit Network, Inc.
 2901 Hubbard, Pod-G
 Ann Arbor, MI 48105
 Phone: (313) 936-3000

Krol & Hoffman [Page 11]

/data/webs/external/dokuwiki/data/pages/rfc/rfc1462.txt · Last modified: 1993/05/25 22:55 by

Donate Powered by PHP Valid HTML5 Valid CSS Driven by DokuWiki