Personalities-3

Ray Tomlinson

Raymond Samuel Tomlinson (born 1941) is a programmer who implemented an email system in 1971. It was the first system able to send mail between users on different hosts connected to the ARPAnet (previously, mail could only be sent to others who used the same computer). To achieve this, he used the @ sign to separate the user from their machine, which has been used in email addresses ever since.
The first email sent by him is not preserved and had content he describes as insignificant, something like "QWERTYUIOP". This is commonly misquoted as "The first e-mail was QWERTYUIOP"
At first, his email messaging system wasn't thought to be a big deal. When Tomlinson showed it to a colleague he said "Don't tell anyone! This isn't what we're supposed to be working on." [3]

He is a graduate of Rensselaer Polytechnic Institute and a long-time employee of BBN.

Tomlinson was born in Amsterdam, New York, but his family soon moved to the small, unincorporated village of Vail Mills, New York. He attended the Broadalbin Central School in nearby Broadalbin, New York. He attended Rensselaer Polytechnic Institute in Troy, New York where he participated in the co-op program with IBM. He received a Bachelor of Science degree in Electrical Engineering from Rensselaer in 1963.

After graduating from RPI, he entered the Massachusetts Institute of Technology to continue his electrical engineering education. At MIT, Tomlinson worked in the Speech Communication Group and developed an analog-digital hybrid speech synthesizer as the subject of his Master's thesis. He received a S.M. in Electrical Engineering degree in 1965.

In 1967 he joined the technology company of Bolt Beranek and Newman where he helped develop the TENEX operating system including ARPANET Network Control Protocol and TELNET implementations. He wrote a file-transfer program called CPYNET to transfer files through the ARPANET. Tomlinson was asked to change a program called SNDMSG, which sent messages to other users of a time-sharing computer, to run on TENEX. He added code he took from CPYNET to SNDMSG so messages could be sent to users on other computers — the first email.

Leonard Kleinrock:

Leonard Kleinrock, Ph.D. (born 1934) is a computer scientist, and a professor of computer science at UCLA, who made several important contributions to the field of computer networking, in particular to the theoretical side of computer networking. He also played an important role in the development of the ARPANET at UCLA.

His most well-known and significant work is his early work on queueing theory, which has applications in many fields, among them as a key mathematical background to packet switching, the basic technology behind the Internet. His initial contribution to this field was his doctoral thesis in 1962, published in book form in 1964; he later published several of the standard works on the subject.

He has described this work as:

"Basically, what I did for my PhD research in 1961–1962 was to establish a mathematical theory of packet networks ..."
His theoretical work on hierarchical routing, done in the late 1970s with his then-student Farouk Kamoun, is now critical to the operation of today's world-wide Internet.