Una pequeña biografía de Len
Kleinrock.
Origen:
http://computer.org/internet/v1n3/kleinrock9702.htm
Idioma: Inglés.
At MIT, he found that the vast majority of his
classmates were doing their Ph.D. research in the overpopulated area of
Information Theory. This was not for him, and instead he chose to break new
ground in the virtually unknown area of data networks. Indeed, in 1959, he
submitted a Ph.D. proposal to study data networks, thus launching the technology
which eventually led to the Internet. He completed his work in 1962 which was
later published in 1964 by McGraw-Hill as an MIT book entitled "Communication
Nets". In this work, he developed the basic principles of packet switching, thus
providing the fundamental underpinnings for that technology. These principles (along
with his subsequent research) continue to provide a basis for today's Internet
technology. Kleinrock is arguably the world's leading authority and researcher
in the field of computer network modeling, analysis and design and a father of
the Internet.
But the commercial world was not ready for data networks and his work lay
dormant for most of the 1960's as he continued to publish his results on
networking technology while at the same time rising rapidly through the
professorial ranks at UCLA where he had joined the faculty in 1963. In the mid-1960's,
the Advanced Research Projects Agency (ARPA) - which was created in 1958 as the
United States' response to Sputnik - became interested in networks. ARPA had
been supporting a number of computer scientists around the country and, as new
researchers were brought in, they naturally asked ARPA to provide a computer on
which they could do their research; however, ARPA reasoned that this community
of scientists would be able to share a smaller number of computers if these
computers were connected together by means of a data network. Because of his
unique expertise in data networking, they called him to Washington to play a key
role in preparing a functional specification for the ARPANET - a government-supported
data network that would use the technology which by then had come to be known as
"packet switching".
The specification for the ARPANET was prepared in 1968, and in January 1969, a
Cambridge-based computer company, Bolt, Beranek and Newman (BBN) won the
contract to design, implement and deploy the ARPANET. It was their job to take
the specification and develop a computer that could act as the switching node
for the packet-switched ARPANET. BBN had selected a Honeywell minicomputer as
the base on which they would build the switch.
Due to Kleinrock's fundamental role in establishing data networking technology
over the preceding decade, ARPA decided that UCLA, under Kleinrock's leadership,
would become the first node to join the ARPANET. This meant that the first
switch (known as an Interface Message Processor - IMP) would arrive on the Labor
Day weekend, 1969, and the UCLA team of 40 people that Kleinrock organized would
have to provide the ability to connect the first (host) computer to the IMP.
This was a challenging task since no such connection had ever been attempted. (This
minicomputer had just been released in 1968 and Honeywell displayed it at the
1968 Fall Joint Computer Conference where Kleinrock saw the machine suspended by
its hooks at the conference; while running, there was this brute whacking it
with a sledge hammer just to show it was robust. Kleinrock suspects that that
particular machine is the one that was delivered by BBN to UCLA.) As it turns
out, BBN was running two weeks late (much to Kleinrock's delight, since he and
his team badly needed the extra development time); BBN, however, shipped the IMP
on an airplane instead of on a truck, and it arrived on time. Aware of the
pending arrival date, Kleinrock and his team worked around the clock to meet the
schedule. On the day after the IMP arrived (the Tuesday after Labor Day), the
circus began - everyone who had any imaginable excuse to be there, was there.
Kleinrock and his team were there; BBN was there; Honeywell was there (the IMP
was built out of a Honeywell minicomputer); Scientific Data Systems was there (the
UCLA host machine was an SDS machine); AT&T long lines was there (we were
attaching to their network); GTE was there (they were the local telephone
company); ARPA was there; the UCLA Computer Science Dept. administration was
there; the UCLA campus administration was there; plus an army of Computer
Science graduate students was there. Expectations and anxieties were high
because, everyone was concerned that their piece might fail. Fortunately, the
team had done its job well and bits began moving between the UCLA computer and
the IMP that same day. By the next day they had messages moving between the
machines. THUS WAS BORN THE ARPANET, AND THE COMMUNITY WHICH HAS NOW BECOME THE
INTERNET!
A month later the second node was added (at Stanford Research Institute) and the
first Host-to-Host message ever to be sent on the Internet was launched from
UCLA. This occurred in early October when Kleinrock and one of his programmers
proceeded to "logon" to the SRI Host from the UCLA Host. The procedure was to
type in "log" and the system at SRI was set up to be clever enough to fill out
the rest of the command, namely to add "in" thus creating the word "login". A
telephone headset was mounted on the programmers at both ends so they could
communicate by voice as the message was transmitted. At the UCLA end, they typed
in the "l" and asked SRI if they received it; "got the l" came the voice reply.
UCLA typed in the "o", asked if they got it, and received "got the o". UCLA then
typed in the "g" and the darned system CRASHED! Quite a beginning. On the second
attempt, it worked fine!
Little did those pioneers realize what they had created. Indeed, most of the
ARPA-supported researchers were opposed to joining the network for fear that it
would enable outsiders to load down their "private" computers. Kleinrock had to
convince them that joining would be a win-win situation for all concerned, and
managed to get reluctant agreement in the community. By December 1969, four
sites were connected (UCLA, Stanford Research Institute, UC Santa Barbara, and
the University of Utah) and UCLA was already conducting a series of extensive
tests to debug the network. Indeed, under Kleinrock's supervision, UCLA served
for many years as the ARPANET Measurement Center (in one interesting experiment
in the mid-1970's, UCLA managed to control a geosynchronous satellite hovering
over the Atlantic Ocean by sending messages through the ARPANET from California
to an East Coast satellite dish). As head of the Center, it was Kleinrock's
mission to stress the network to its limits and, if possible, expose its faults
by "crashing" the net; in those early days, Kleinrock could bring the net down
at will, each time identifying and repairing a serious network fault. Some of
the faults he uncovered were given descriptive names like Christmas Lockup and
Piggyback Lockup. By mid-1970, ten nodes were connected, spanning the USA. BBN
designed the IMP to accommodate no more than 64 computers and only one network.
Today, the Internet has millions of computers and hundreds of thousands of
networks! Electronic mail (email) was an ad-hoc add-on to the network in those
early days and it immediately began to dominate network traffic; indeed, the
network was already demonstrating its most attractive characteristic, namely,
its ability to promote "people- to-people" interaction. The ARPANET evolved into
the Internet in the 1980's and was discovered by the commercial world in the
late `80's; today, the majority of the traffic on the Internet is from the
commercial sector, whereas it had earlier been dominated by the scientific
research community. Indeed, no one in those early days predicted how enormously
successful data networking would become.
