History Of Internet And Communications

Published Date: 02 Nov 2017

THE INTERNET HAS REVOLUTIONIZED THE COMPUTER AND COMMUNICAtions world like nothing before. The telegraph, telephone, radio, and

computer have all set the stage for the Internet’s unprecedented integration of capabilities. The Internet is at once a worldwide broadcasting

capability, a mechanism for information dissemination, and a medium for

collaboration and interaction between individuals and their computers without regard for geographic location.

The Internet also represents one of the most successful examples of sustained investment and commitment to research and development in information

infrastructure. Beginning with early research in packet

switching, the government, industry, and academia

have been partners in evolving and deploying this

exciting new technology. Today, terms like

"[email protected]" and "http://www.acm.org" trip

lightly off the tongue of random people on the street.1

The Internet today is a widespread information

infrastructure, the initial prototype of what is often

called the National (or Global or Galactic) Information

Infrastructure. Its history is complex and involves

many aspects—technological, organizational, and

community. And its influence reaches not only to the

technical fields of computer communications but

throughout society as we move toward increasing use

of online tools to accomplish electronic commerce,

information acquisition, and community operations.2

Origins

The first recorded description of the social interactions

that could be enabled through networking was a series

of memos written August 1962 by J.C.R. Licklider of

MIT, discussing his "Galactic Network" concept [6].

Licklider envisioned a globally interconnected set of

The Past and Future History

1

Perhaps this is an exaggeration due to the lead author’s residence in Silicon Valley.

2

For a more detailed version of this article, see http://www.isoc.org/internet-history. COMMUNICATIONS OF THE ACM February 1997/Vol. 40, No. 2 103

computers through which everyone could quickly

access data and programs from any site. In spirit, the

concept was much like the Internet today. While at

DARPA,3

he convinced the people who would be his

successors there—Ivan Sutherland, Bob Taylor, and

MIT researcher Lawrence G. Roberts—of the importance of this networking concept.

Leonard Kleinrock of MIT published the first paper

on packet switching theory in July 1961 [5]. Kleinrock convinced Roberts of the theoretical feasibility of

communications using packets rather than circuits—a

major step toward computer networking. The other

key step was to make the computers talk to each other.

Exploring this idea in 1965 while working with

Thomas Merrill, Roberts connected the TX-2 computer in Massachusetts to the Q-32 in California

through a low-speed dial-up telephone line [8], creating the first-ever (though small) wide-area computer

network. The result of this experiment: confirmation

that time-sharing computers could work well

together, running programs and retrieving data as necessary on remote machines, but that the circuitswitched telephone system was totally inadequate for

the job. Thus confirmed was Kleinrock’s conviction of

the need for packet switching.

In late 1966, Roberts went to DARPA to develop

the computer network concept and quickly put

together a plan for the ARPANET, publishing it in

1967 [7]. Bolt, Beranek and Newman Corp. (BBN),

under Frank Heart’s leadership, developed the

ARPANET switches (called IMPs), with Robert Kahn

responsible for overall system design. Howard Frank

and his team at Network Analysis Corp. worked with

Roberts to optimize the network topology and economics. Due to Kleinrock’s early development of

packet switching theory and his focus on analysis,

design, and measurement, his Network Measurement

Center at UCLA was selected as the first node on the

ARPANET. All this came together September 1969

when BBN installed the first switch at UCLA and the

first host computer was connected. In December 1970,

the Network Working Group (NWG) under Steve

Crocker finished the initial ARPANET host-to-host

protocol, called the Network Control Protocol (NCP).

As the ARPANET sites completed implementing

NCP during 1971–1972, network users finally could

begin to develop applications.

In October 1972, a large, successful demonstration

of the ARPANET took place—the first public demonstration of this new network technology. Also in 1972,

electronic mail, the initial "hot" application, was introduced. In March, Ray Tomlinson of BBN wrote the

basic email message send-and-read software, motivated

by ARPANET developers’ need for an easy coordination mechanism. From there, email took off as the most

popular network application and as a harbinger of the

kind of people-to-people communication activity we

see on the World-Wide Web today.

Initial Internetting Concepts

The original ARPANET grew into the Internet based

on the idea that there would be multiple independent

networks of rather arbitrary design. Beginning with

the ARPANET as the pioneering packet-switching

network, it soon grew to include packet satellite networks, ground-based packet radio networks, and other

networks. Today’s Internet embodies a key underlying

technical idea: open-architecture networking. In this

approach, the choice of any individual network technology is not dictated by a particular network architecture but can be selected freely by a provider and

made to interwork with the other networks through a

meta-level "internetworking architecture." Each network can be designed to fit a specific environment and

user requirements.

The idea of open-architecture networking—introduced by Kahn in late 1972 shortly after arriving at

DARPA—was guided by four critical ground rules:

• Each distinct network had to stand on its own, and

no internal changes could be required of any such

network before being connected to the Internet.

• Communications would be on a best-effort basis. If

a packet didn’t make it to the final destination, it

would quickly be retransmitted from the source.

• Black boxes (later called gateways and routers)

would be used to connect the networks. No infor-

3The Advanced Research Projects Agency (ARPA) changed its name to Defense

Advanced Research Projects Agency (DARPA) in 1971, back to ARPA in 1993, and

back to DARPA in 1996. We refer throughout to DARPA, the current name.

The Internet was conceived

in the era of time-sharing,

but has survived into the era of

personal computers, client/server

and peer-to-peer computing,

and the network computer.mation would be retained by the gateways about

individual flows of packets passing through them,

keeping them simple and avoiding complicated

adaptation and recovery from various failure modes.

• There would be no global control at the operations

level.

Kahn first began work on a communications-oriented set of operating system principles while at BBN

[4]. After joining DARPA and initiating the Internet

program, he asked Vinton Cerf (then at Stanford University) to work with him on the detailed design of the

protocol. Cerf had been deeply involved in the original

NCP design and development and was already knowledgeable about interfacing to existing operating systems. So, armed with Kahn’s architectural approach to

communications and with Cerf’s NCP experience,

these two teamed up to spell out the details of what

became the Transmission Control Protocol/Internet

Protocol (TCP/IP).

The original Cerf/Kahn paper [1] on the Internet

described a protocol, called TCP, providing all the

Internet’s transport and forwarding services. Kahn had

intended that TCP would support a range of transport

services—from the totally reliable sequenced delivery

of data (virtual circuit model) to a datagram service in

which the application made direct use of the underlying network service, a process that could imply occasional lost, corrupted, or reordered packets.

However, the initial effort to implement TCP

resulted in a version allowing only virtual circuits.

This model worked fine for file transfer and remote

login applications, but some of the early work on

advanced network applications, particularly packet

voice in the 1970s, made clear that in some cases

packet losses should not be corrected by TCP but left

to the application to deal with. This insight led to a

reorganization of the original TCP into two protocols—the simple IP providing only for addressing and

forwarding of individual packets and the separate TCP

concerned with such service features as flow control

and recovery from lost packets. For applications that

did not want the services of TCP, an alternative called

the User Datagram Protocol (UDP) was added to provide direct access to the basic IP service.

In addition to email, file transfer, and remote login,

other applications were proposed in the early days of the

Internet, including packet-based voice communication

(the precursor of Internet telephony), various models of

file and disk sharing, and early "worm" programs illustrating the concept of agents (and viruses). The Internet

was not designed for just one application but as a general infrastructure on which new applications could be

conceived, exemplified later by the emergence of the

Web. The general-purpose nature of the service provided by TCP and IP makes this possible.

Proving the Ideas

DARPA funded three efforts to implement TCP: Stanford (Cerf), BBN (Tomlinson), and University College

London (Peter Kirstein). The Stanford team produced a

detailed specification, yielding within about a year three

independent interoperable implementations of TCP.

This was the beginning of long-term experimentation and development of Internet concepts and technology—along with the constituent networking

technologies [3]. Each expansion has involved new

challenges. For example, the early implementations of

TCP were done for large time-sharing systems. When

desktop computers first appeared, it was thought by

some that TCP was too big and complex to run on a

personal computer. But David Clark and his research

group at MIT produced an implementation first for

the Xerox Alto (the early personal workstation developed at Xerox PARC) and then for the IBM PC, showing that workstations, as well as large time-sharing

systems, could be part of the Internet.

Widespread development of local-area networks

(LANs), PCs, and workstations in the 1980s allowed

the nascent Internet to flourish. Ethernet technology

(developed by Bob Metcalfe at Xerox PARC in 1973)

is now probably the dominant network technology in

the Internet and PCs and workstations the dominant

computers. The increasing scale of the Internet also

resulted in several new approaches. For example, the

Domain Name System was invented (by Paul Mockapetris, then at USC’s Information Sciences Institute)

to provide a scalable mechanism for resolving hierarchical host names (e.g., www.acm.org) into Internet

addresses. The requirement for scalable routing

104 February 1997/Vol. 40, No. 2 COMMUNICATIONS OF THE ACM

The most pressing question for the

future of the Internet is not how

the technology will change, but

how the process of change and

evolution itself will be managed.approaches led to a hierarchical model of routing, with

an Interior Gateway Protocol (IGP) used inside each

region of the Internet and an Exterior Gateway Protocol (EGP) used to tie the regions together. New

approaches for address aggregation, particularly classless interdomain routing (CIDR), were recently introduced to control the size of router tables.

Another major challenge was how to propagate the

changes to the software, particularly host software.

DARPA supported the University of California at

Berkeley to investigate modifications to the Unix operating system, including incorporating TCP/IP developed at BBN. Although Berkeley later rewrote the

BBN code to more efficiently fit into the Unix system

and kernel, incorporation of TCP/IP into the Unix

BSD system proved a critical element in dispersing the

protocols to the research community. Much of the

computer science community began using Unix BSD

in their day-to-day computing environments. Looking

back, the strategy of incorporating Internet protocols

into a supported operating system for the research

community was a key element in the Internet’s successful widespread adoption.

TCP/IP was adopted as a defense standard in 1980,

enabling the defense community to begin sharing the

DARPA Internet technology base and leading directly

to the partitioning of the military and non-military

communities. By 1983, ARPANET was being used by

a significant number of defense R&D and operational

organizations. The transition of ARPANET from NCP

to TCP/IP in 1983 permitted it to be split into a MILNET supporting operational requirements and an

ARPANET supporting research needs.

Thus, by 1985, the Internet was established as a

technology supporting a broad community of

researchers and developers and was beginning to be

used by other communities for daily computer communications. Email was being used broadly across several communities, often with different systems,

demonstrating the utility of broad-based electronic

communications between people.

Transition to Widespread Infrastructure

At the same time Internet technology was being experimentally validated and widely used by a subset of

computer science researchers, other networks and networking technologies were being pursued. The usefulness of computer networking—especially

email—demonstrated by DARPA and Department of

Defense contractors on the ARPANET was not lost on

other communities and disciplines, so that by the mid-

1970s computer networks began springing up wherever funding was found for the purpose, including the

Department of Energy’s MFENET and HEPNET,

NASA’s SPAN, the computer science community’s

CSNET, the academic community’s BITNET, and

USENET based on Unix UUCP protocols. Commercial networking technologies were being pursued as

well, including IBM’s SNA, Xerox’s XNS, and Digital

Equipment Corp.’s DECNET.

It remained for the British JANET (1984) and U.S.

NSFNET (1985) programs to explicitly announce their

intent to serve the entire higher education community,

regardless of discipline. In 1985, Dennis Jennings came

from Ireland for a year to lead the National Science

Foundation’s NSFNET program. He helped NSF make

a critical decision—that TCP/IP would be mandatory

for NSFNET. And when Stephen Wolff took over the

NSFNET program in 1986, he recognized the need for

a wide-area networking infrastructure to support the

general academic and research community, as well as

the need to develop a strategy for establishing such

infrastructure to ultimately be independent of direct

federal funding.

Policies and strategies were adopted to achieve that

end. So while federal agencies shared the cost of common

infrastructure, such as trans-oceanic circuits, NSF

encouraged regional networks of the NSFNET to seek

commercial, non-academic customers. And NSF

enforced an acceptable-use policy, prohibiting Backbone

use for purposes "not in support of research and education." The predictable (and intended) result of encouraging commercial network traffic at the local and

regional levels, while denying its access to national-scale

transport, was the emergence and growth of "private,"

competitive, long-haul networks, such as PSI, UUNET,

ANS CO+RE, and (later) others.

NSF’s privatization policy culminated in April

1995 with the defunding of the NSFNET Backbone.

The funds thereby recovered were (competitively)

redistributed to regional networks to buy nationalscale Internet connectivity from the now numerous,

private, long-haul networks. The Backbone had made

the transition from a network built from routers out of

the research community (David Mills’s "Fuzzball"

routers) to commercial equipment. In its eight-and-ahalf-year lifespan, the Backbone had grown from six

nodes with 56Kbps links to 21 nodes with multiple

45Mbps. It also saw the Internet grow to more than

50,000 networks on all seven continents and outer

space (with 29,000 networks in the U.S.).

Such was the weight of the NSFNET program’s

COMMUNICATIONS OF THE ACM February 1997/Vol. 40, No. 2 105ecumenism and funding ($200 million, 1986–1995)

and the quality of the protocols themselves that by

1990 when the ARPANET itself was finally decommissioned, TCP/IP had supplanted or marginalized

most other wide-area computer network protocols

worldwide, and IP was on its way to becoming

the bearer service for the Global Information

Infrastructure.

Documentation’s Key Role

A key to the rapid growth of the Internet has been free

and open access to the basic documents, especially the

specifications of the protocols. The beginnings of the

ARPANET and the Internet in the university research

community promoted the academic tradition of open

publication of ideas and results. However, the normal

cycle of traditional academic publication was too formal and too slow for the dynamic exchange of ideas

essential to creating networks. In 1969, a key step was

taken by S. Crocker (then at UCLA) in establishing the

request for comments (or RFC) series of notes

[2].These memos were intended to be an informal fast

means of distribution for sharing ideas among network

researchers. At first the RFCs were printed on paper

and distributed via postal mail. As the File Transfer

Protocol (FTP) came into use, the RFCs were prepared

as online files and accessed via FTP. Now, the RFCs are

easily accessed via the Web at dozens of sites around

the world. SRI, in its role as Network Information

Center, maintained the online directories. Jon Postel

acted as RFC editor and as manager of centralized

administration of required protocol number assignments—roles he continues to this day.

The effect of the RFCs was to create a positive feedback loop, so ideas or proposals presented in one RFC

would trigger other RFCs. When consensus (or a least

a consistent set of ideas) would come together, a specification document would be prepared; such specifications would then be used as the basis for

implementations by the various research teams. The

RFCs are now viewed as the "documents of record" in

the Internet engineering and standards community

and will continue to be critical to future net evolution

while furthering the net’s initial role of sharing information about its own design and operations.

Formation of a Broad Community

The Internet is as much a collection of communities as

a collection of technologies, and its success is largely

attributable to satisfying basic community needs as

well as utilizing the community effectively to push the

infrastructure forward. Community spirit has a long

history, beginning with the early ARPANET, whose

early researchers worked as a close-knit community

(the ARPANET Working Group) to accomplish the

initial demonstrations of packet switching technology.

Likewise, the packet satellite, packet radio, and other

DARPA computer science research programs were

multi-contractor collaborative activities that used any

available mechanisms to coordinate their efforts, starting with email, and adding file sharing, remote access,

and eventually Web capabilities.

In the late 1970s, recognizing that the growth of

the Internet was accompanied by the growth of the

interested research community and therefore an

increased need for coordination mechanisms, Cerf,

then manager of the DARPA Internet program,

formed several coordination bodies, including the

Internet Configuration Control Board (ICCB), chaired

by Clark. The ICCB was an invitation-only body

assisting Cerf in managing the burgeoning Internet

activity.

In 1983, when Barry Leiner took over management

of the Internet program at DARPA, he and Clark recognized that the continuing growth of the Internet

community demanded a restructuring of the coordination mechanisms.

The ICCB was disbanded and replaced by a structure of Task Forces, each focused on a particular area of

the technology (e.g., routers and end-to-end protocols). The Internet Activities Board (IAB) included the

chairs of the Task Forces.

After some changing membership on the IAB, Phill

Gross became chair of a revitalized Internet Engineering Task Force (IETF)—at the time only one of the

IAB Task Forces. The growth of the Internet in the

mid-1980s resulted in vastly increased attendance at

IETF meetings, and Gross had to create substructure

to the IETF in the form of working groups.

The expanded community also meant that DARPA

was no longer the only major player when it came to

funding the Internet. In addition to NSFNET and the

various U.S. and international government-funded

activities, interest in the commercial sector was beginning to grow. And in 1985, when both Kahn and

Leiner left DARPA, there was a significant decrease in

DARPA's Internet activity. The IAB was left without

a primary sponsor and so increasingly assumed the

mantle of leadership.

Continued growth resulted in even further substructure within both the IAB and IETF, while growth

in the commercial sector brought increased concern

106 February 1997/Vol. 40, No. 2 COMMUNICATIONS OF THE ACMregarding the standards process. The twin motivations

of making the process open and fair and the need to

win Internet community support eventually led in

1991 to formation of the Internet Society, under the

auspices of Kahn’s Corporation for National Research

Initiatives (CNRI) and the leadership of Cerf, who was

then with CNRI.

In 1992, yet another reorganization took place. The

IAB was reorganized and renamed the Internet Architecture Board. A more peer-like relationship was

defined between the new IAB and Internet Engineering Steering Group (IESG), with the IETF and IESG

taking greater responsibility for approving standards.

Ultimately, a cooperative and mutually supportive

relationship was formed among the IAB, IETF, and the

Internet Society.

The Web’s recent development and widespread

deployment brings a new community, as many of the

people now working on the Web didn’t view themselves primarily as network researchers and developers.

Therefore, in 1995, a new coordination organization

was formed—the World-Wide Web Consortium

(W3C), initially led from MIT’s Laboratory for Computer Science by Al Vezza and Tim Berners-Lee, the

Web’s inventor. Today, the W3C is responsible for

evolving the various protocols and standards associated

with the Web.

Commercialization

Commercialization of the Internet has involved not

only development of competitive, private network services, but commercial products implementing Internet

technology. In the early 1980s, dozens of vendors were

incorporating TCP/IP into their products because they

saw buyers for that approach to networking. Unfortunately, they lacked real information about how the

technology was supposed to work and how their customers planned to use the approach.

In 1985, recognizing the lack of available information and appropriate training, Daniel Lynch in cooperation with the IAB arranged a three-day workshop for

all vendors to learn how TCP/IP worked and what it

still could not do well. Speakers were mostly from the

DARPA research community where they had developed these protocols and used them in day-to-day

work. Approximately 250 vendor representatives heard

50 inventors and experimenters.

The first Interop trade show, September 1988,

demonstrated interoperability between vendor products and was attended by 50 companies and 5,000

engineers from potential customer organizations.

Interop has grown immensely since then, and today is

an annual event in seven locations around the world for

an audience of more than 250,000 who want to learn

which products seamlessly work with which other

products and about the latest technology.

In the last few years, we have seen a new phase of

commercialization. Originally, commercial efforts

mainly comprised vendors providing the basic networking products and service providers offering

connectivity and basic Internet services. The Internet has now become almost a "commodity" service,

and much of the latest attention has been on the use

of this global information infrastructure as support

COMMUNICATIONS OF THE ACM February 1997/Vol. 40, No. 2 107

"In the future, computers will shop for us. You will log into

a virtual supermarket and order food, they will send it to you

the next day. School will change too. You could have school

at home and fax your homework in, but you won’t make any

friends that way. We will have to make friends on the

Internet. Libraries will still be there, but not many people will

visit them anymore and they will be knocked down.

—Nicholas Phibbs, age 12

"

Surrey, UKfor other commercial services.

This activity has been accelerated by the widespread

and rapid adoption of browsers and Web technology,

giving users easy access to information linked around

the globe. Products are available for finding, sending,

and retrieving that information, and many of the latest

developments seek to provide increasingly sophisticated information services on top of basic Internet data

communications.

History of the Future

The Internet was conceived in the era of time-sharing,

but has survived into the era of personal computers,

client/server and peer-to-peer computing, and the network computer. It was designed before LANs existed,

but has evolved to accommodate LANs as well as more

recent ATM and frame-switched services. It was envisioned as supporting a range of functions—from file

sharing and remote login to resource sharing and collaboration, and has spawned email and more recently

the Web. But most important, it started as the creation of a small band of dedicated researchers and has

grown to be a commercial success with billions of dollars invested annually.

One should not conclude that the Internet is complete. The Internet is a creature of the computer, not

the traditional networks of the telephone or television

industries. It will—indeed it must—continue changing at the speed of the computer industry to remain relevant. It is now changing to provide such new services

as real-time transport, supporting, for example, audio

and video streams. The availability of pervasive networking—that is, the Internet itself—along with powerful affordable computing and communications in

portable form (e.g., laptop computers, two-way pagers,

PDAs, cellular phones) makes possible a new paradigm

of nomadic computing and communications.

This evolution will bring us new applications—

Internet telephone and, further out, Internet television. It will also permit more sophisticated forms of

pricing and cost recovery, a perhaps painful requirement in this commercial world. It is changing to

accommodate yet another generation of underlying

network technologies with different characteristics and

requirements—from broadband residential access to

satellites. New modes of access and new forms of service will spawn new applications that in turn will

drive further evolution of the net itself.

The most pressing question for the future of the

Internet is not how the technology will change, but

how the process of change and evolution itself will be

managed. Internet architecture has always been driven

by a core group of designers, but the form of that group

has changed as the number of interested outside parties

has grown. With the success of the Internet has come a

proliferation of stakeholders—now with an economic as

well as an intellectual investment in the network. We

see, for example, in the debates over control of the

domain namespace and the form of the next-generation

IP addresses a struggle to find the next social structure

to guide the Internet. However, that structure is more

difficult to define, given the large number of stakeholders. The industry also struggles to find the economic rationale for the huge investment needed for

future growth to, for example, upgrade residential

access to more suitable technology. If the Internet

stumbles, it will not be because we lack technology,

vision, or motivation but because we cannot set a direction and march collectively into the future.