Tech Talk Radio
Sponsored by Stratford University
Origin of the Internet
As Viewed by its Creators
Interview With Vint Cerf, Bob Kahn, and Don Heath
Broadcast Date: June 17, 2000
Listen Now (MP3)
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Introduction and Guests top
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Stratford
University and Tech Talk were honored to have as guests three leaders of
the Internet revolution. Dr. Vinton Cerf and Dr. Robert Kahn created the protocols
and the architecture behind the Internet. Mr. Don Heath is the President and CEO
of the Internet Society. In this show we trace the development of the Internet
from the early ARPA-funded efforts to today. We then looked at the future and
took a peek at an interplanetary Internet.
Dr. Vinton Cerf (left), Dr. Robert Kahn, Mr. Donald Heath,
and Dr. Richard Shurtz outside the Virtual Faculty Lounge
after the broadcast of Tech Talk. |
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Dr. Vinton G. Cerf top
Vint Cerf was Senior Vice President for Internet
Architecture and Technology at the MCI WorldCom. He is now working as Chief Internet Evangelist at Google. He is co-inventor of the TCP/IP protocol and Internet Architecture
with Bob Kahn while serving at Stanford and DARPA. He is a Distinguished Visiting
Scientist at the Jet Propulsion Laboratory, working on the architecture and design
of an interplanetary Internet. He served as first President of the Internet Society,
while at CNRI. In addition, Vint is a fine wine connoisseur and gourmet cook. He, along
with Kahn, is frequently called the "Father of the Internet."
Dr. Robert E. Kahn top
Bob Kahn is Chairman, CEO, and President of
the Corporation for National Research Initiatives (www.cnri.reston.va.us).
He is co-inventor of the TCP/IP protocol and Internet Architecture with Vint
Cerf, while serving at MIT, BBN (Bolt, Beranek, and Newman), and DARPA. He coined
the term National Information Infrastructure (NII) which later became more widely
known as the Information Super Highway (the name proposed by Al Gore). A complete summary of his accomplishments
can be found in his CNRI
Biography. He, along with Cerf, is frequently called the "Father of
the Internet."
Mr. Don Heath top
Don Heath is President and CEO of the Internet
Society (www.isoc.org). He
is Chair of the International Ad Hoc Committee (IAHC), a coalition of participants
from the broad Internet community, working to satisfy the requirement for enhancements
to the Internet's global Domain Name System (DNS). He is currently a member
of the Advisory Committee on Telecommunications to the government of Ireland.
A complete summary of his accomplishments can be found in his ISOC
Trustee's Biography.
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Early Years of Internetworking top |
| "The goal of Internetting (or Internetworking) research was to "create an architecture for interconnecting independent networks that could then be federated into a seamless whole without changing any of the underlying networks." (Kahn and Cerf) |
Understanding
the significance of this statement requires that we go back to the state of affairs
in computers and computer networks in the late sixties and early seventies. At
that time, we had mainframe computers that were connected to dumb terminals. The
goal was to network many terminals to the mainframe so that resources could be
shared. Since local area networks (LANs) and files servers did not exist outside
of the Xerox Palo Alto Reseach Center, the total number of networks was expected
to be less than 100 for the entire country!
The first wide area network was the ARPANET (proposed
in 1967). Its goal was to connect various mainframe computers for the purpose
of time sharing resources. ARPANET used a 50,000 bits per second line speed. This
initial network used a revolutionary concept of "packet switching" instead
of the traditional "circuit switching" methods of the telephone companies.
Packet switching was more suited to the bursty type of data rates of computer
communication. In packet switching each packet was sent over the network after
suitable identifiers had been placed at the front of the packet (i.e. in the header).
E-mail was the first "hot" application that was introduced on the ARPANET.
Other applications included File Transfer Protocol (ftp) and Telnet (a terminal
emulator).
In the early seventies, the Advanced Research Projects
Agency (ARPA) developed two other packet switched technologies, one for synchronous
satellites (SATNET) and the other for ground-based packet radio (PRNET). Neither
of these networks could communicate through the ARPANET. Kahn's decision to link
these networks as separate and independent networks resulted in the creation of
new internetworking technologies. Kahn collaborated with Cerf on both the protocols
and the architecture of this Internetworking project. Out of this collaboration
was borne Transmission Control Protocol/Internet Protocol (TCP/IP) and ultimately
the Internet. This protocol would be divided into two software "layers," with TCP in charge of connection management and reliability and IP in charge of
packet delivery. (It should be noted that the original ARPANET did not use
TCP/IP.)
The new Internetworking architecture included universal
addressing and end-to-end connection management. The end-to-end management meant
that the end-point computers were responsible for error recovery rather than the
underlying data circuits. The universal addressing system meant that any computer
on any network could be reached. This numbering system served the same purpose
as a phone number in the Telco system. Networks were connected using devices called
gateways (now called routers). DARPA contracted with Cerf's group to develop the
initial protocol design, with BBN and University of London to build implementations
of the protocol. This program connected ARPANET, SATNET, and PRNET. The ARPANET
was converted to TCP/IP as it standard protocol on January 1, 1983.
Under Kahn and Cerf's leadership, government policy
dictated that the TCP/IP protocols remain open and unclassified. The source code
was released to the community at large for review and refinement. These refinements
were controlled through an Informal Request for Comment (RFC) process that was
managed by the Internet Engineering Task Force.
During this initial period of development, many
individuals contributed to this effort for reasons other than financial gain.
A spirit of community and selflessness permeated this community. This atmosphere
contributed to the ultimate acceptance and expansion of the technology to become
the de facto worldwide internetworking standard.
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Growth and Privatization of the Internet top |
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In
the mid 1980s, the National Science Foundation (NSF) commissioned a high performance
network based on TCP/IP internetworking architecture of the ARPANET. IBM and MCI
won the contract and completed the construction within two years. NSFNET became
the backbone of the ARPANET until ARPANET's decommissioning in 1989. New networks
were permitted to connect to the NSFNET backbone and so began the expansion.
The widespread acceptance of the personal computers and
the deployment of Ethernet Local Area Networks (LANs) during the late eighties
dramatically increased the number of networks attached to the Internetwork. The
layered TCP/IP protocol structure could easily encompass this shift from mainframe/terminal
to client/server networks. The data circuit for each network would simply be required
to have a common application programming interface (API) for communication with
the IP layer. In the same way, TCP would provide an API for any applications that
may request network services. At this point we have the final definition of the
four protocol layers (Application, TCP, IP, Datalink).
The Internet
Society was started in 1991, under the auspices of Kahn's CNRI and the leadership
of Cerf, then with CNRI. The Internet Engineering Task Force and the Internet
Architecture Board were incorporated into ISOC. ISOC manages the Internet standards
process. Cerf became the first ISOC president.
NSF restrictions prohibited commercial usage of
the backbone. That began to change as the pressure for commercial use mounted.
First MCI Mail was added to the system, then the for-profit companies UUNET and
PSINET were connected. Shortly thereafter Congress permitted commercial use of
the NSFNET backbone. In 1995, NSF ceased its support for the NSFNET. The Internet,
as we know it today, was born.
The rapid expansion of the Internet strained the
technology. In order to support the addition of thousands of new networks, the
addressing scheme was modified to assign more bits to the network address (out
of a total address space of 32 bits). Initially only 8 bits were reserved for
the network address. This network address space was expanded to include three
lengths (8, 16 or 24 bits out of a total of 32 bits). These addresses were classed
as A, B, or C respectively. To more efficiently allocate the address space, this
system was modified to permit a variable number of bits to be assigned to the
network address. Addresses were then aggregated to reduce the size of routing
tables using Classless Interdomain Routing (CIDR). The next improvement in addressing
will come with the next version of IP (IPv6) which will have a 128 bit address.
In order to support the addition of so many hosts
to the network, an improved Domain Name System (DNS) had to be deployed. DNS translates
a name like www.stratford.edu into an IP address. This lookup process is
called Name Resolution. Seven top level domains (edu, gov, mil, int, net, org,
com) were created to distribute the load.
In 1993, the browser was invented to help researchers
share results more conveniently over the Internet. The browser read files stored
on web servers. These servers formed an information network that could be reached
by clicking on any hyperlinked text. The network of web servers became known as
the World Wide Web (www). Netscape commercialized the browser in 1994 and the
wide-spread adoption of Internet began in earnest.
The Internet, in its current configuration, is
global and not controlled by any country, but rather by an elected group within
ISOC. The Internet is supported by the fees that individuals pay to their Internet
Service Provider (ISP). The ISPs pay for their usage of the Internet backbone,
which is operated by the Telcos (MCI, Sprint, AT&T) and others (UUNET, PSINET).
ISOC is supported by individual and corporate memberships. It works because everyone
voluntarily supports the standards defined by ISOC's Internet Engineering Task
Force.
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Future of the Internet top
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The immediate future
will bring the adoption of the next version of IP software (IPv6) Internet Protocol
Version 6 (IPv6). This version will support a large address space (128 bits) and
quality of service specifications for time-sensitive multimedia data (i.e. voice
and video). Cerf, in conjunction with JPL, is working on an Interplanetary Internet.
We may see an Earth-Mars backbone in place by 2008.
The Internet will become more pervasive. Internet
connections will be placed in appliances, cell phones, cars, etc. We will become
globally connected. Wireless connections to the Internet will become the norm.
1-2 Mbps data rates will be the standard. Ultrahigh speed Internet backbones (operating
at terabits per second) will carry this increased traffic load.
New methods for classifying and tracking information
on the Internet will be developed. A digital object infrastructure supported by
a distributed database may be the initial step in that direction.
The societal impact of the Internet will be enormous.
It will accelerate the development of third world nations and the demise of non-democratic
governments by making information available to the masses. We must, however, address
the issues related to access and the digital divide.
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References top
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The bulk of what we discussed can be found in the following two documents.
Internet links
referenced during our discussion are listed below.
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