Sally Jean Floyd (May 20, 1950 – August 25, 2019) was an American
computer scientist
A computer scientist is a scientist who specializes in the academic study of computer science.
Computer scientists typically work on the theoretical side of computation. Although computer scientists can also focus their work and research on ...
known for her work on
computer networking
A computer network is a collection of communicating computers and other devices, such as printers and smart phones. In order to communicate, the computers and devices must be connected by wired media like copper cables, optical fibers, or b ...
. Formerly associated with the
International Computer Science Institute
The International Computer Science Institute (ICSI) is an independent, non-profit research organization located in Berkeley, California, United States. Since its founding in 1988, ICSI has maintained an affiliation agreement with the University ...
in
Berkeley, California
Berkeley ( ) is a city on the eastern shore of San Francisco Bay in northern Alameda County, California, United States. It is named after the 18th-century Anglo-Irish bishop and philosopher George Berkeley. It borders the cities of Oakland, Cali ...
, she retired in 2009 and died in August 2019. She is best known for her work on Internet
congestion control
Network congestion in data networking and queueing theory is the reduced quality of service that occurs when a network node or link is carrying more data than it can handle. Typical effects include queueing delay, packet loss or the blocking of ...
, and was in 2007 one of the top-ten most cited researchers in computer science."Sally Floyd Wins 2007 SIGCOMM Award" ICSI, Sept. 2007 (last visited Oct. 7, 2012).
Biography
Born in
Charlottesville, Virginia
Charlottesville, colloquially known as C'ville, is an independent city (United States), independent city in Virginia, United States. It is the county seat, seat of government of Albemarle County, Virginia, Albemarle County, which surrounds the ...
, Floyd received a
B.A.
A Bachelor of Arts (abbreviated B.A., BA, A.B. or AB; from the Latin ', ', or ') is the holder of a bachelor's degree awarded for an undergraduate program in the liberal arts, or, in some cases, other disciplines. A Bachelor of Arts degree ...
in sociology from the
University of California, Berkeley
The University of California, Berkeley (UC Berkeley, Berkeley, Cal, or California), is a Public university, public Land-grant university, land-grant research university in Berkeley, California, United States. Founded in 1868 and named after t ...
, in 1971. She received an
M.S.
A Master of Science (; abbreviated MS, M.S., MSc, M.Sc., SM, S.M., ScM or Sc.M.) is a master's degree. In contrast to the Master of Arts degree, the Master of Science degree is typically granted for studies in sciences, engineering and medicine ...
in computer science in 1987 and a
Ph.D.
A Doctor of Philosophy (PhD, DPhil; or ) is a terminal degree that usually denotes the highest level of academic achievement in a given discipline and is awarded following a course of graduate study and original research. The name of the deg ...
in 1989, both from UC Berkeley. Her Ph.D. was completed under the supervision of
Richard M. Karp
Richard Manning Karp (born January 3, 1935) is an American computer scientist and computational theorist at the University of California, Berkeley. He is most notable for his research in the theory of algorithms, for which he received a Turing ...
.
Floyd is best known in the field of
congestion control
Network congestion in data networking and queueing theory is the reduced quality of service that occurs when a network node or link is carrying more data than it can handle. Typical effects include queueing delay, packet loss or the blocking of ...
as the inventor of
Random Early Detection
Random early detection (RED), also known as random early discard or random early drop, is a queuing discipline for a network scheduler suited for congestion avoidance.
In the conventional tail drop algorithm, a router or other network componen ...
("RED") active queue management scheme, thus founding the field of Active Queue Management (AQM) with
Van Jacobson
Van Jacobson is an American computer scientist, renowned for his work on TCP/IP network performance and scaling. Almost all
Internet router
A router is a computer and networking device that forwards data packets between computer networks, including internetworks such as the global Internet.
Routers perform the "traffic directing" functions on the Internet. A router is connect ...
s use RED or something developed from it to manage network congestion. Floyd devised the now-common method of adding
delay jitter
In computer networking, packet delay variation (PDV) is the difference in end-to-end one-way delay between selected packets in a flow with any lost packets being ignored. The effect is sometimes referred to as packet jitter, although the defi ...
to message timers to avoid synchronization.IEEE "Sally Floyd" IEEE Global History Network (last visited Oct. 7, 2012).
Floyd, with
Vern Paxson
Vern Edward Paxson is a professor of computer science at the University of California, Berkeley. He also leads the Networking and Security Group at the International Computer Science Institute in Berkeley, California. His interests range from tr ...
, in 1997 identified the lack of knowledge of
network topology
Network topology is the arrangement of the elements (Data link, links, Node (networking), nodes, etc.) of a communication network. Network topology can be used to define or describe the arrangement of various types of telecommunication networks, ...
as the major obstacle in understanding how the Internet works. This paper, "Why We Don't Know How to Simulate the Internet", was re-published as "Difficulties in Simulating the Internet" in 2001 and won the
IEEE Communications Society
The Institute of Electrical and Electronics Engineers (IEEE) is an American 501(c)(3) public charity professional organization for electrical engineering, electronics engineering, and other related disciplines.
The IEEE has a corporate office i ...
's William R. Bennett Prize Paper Award.
Floyd is also a co-author on the standard for TCP
Selective acknowledgement
The Transmission Control Protocol (TCP) is one of the main communications protocol, protocols of the Internet protocol suite. It originated in the initial network implementation in which it complemented the Internet Protocol (IP). Therefore, th ...
(SACK),
Explicit Congestion Notification
Explicit Congestion Notification (ECN) is an extension to the Internet Protocol and to the Transmission Control Protocol and is defined in (2001). ECN allows end-to-end notification of network congestion without dropping packets. ECN is an optio ...
(ECN), the
Datagram Congestion Control Protocol
In computer networking, the Datagram Congestion Control Protocol (DCCP) is a message-oriented transport layer protocol. DCCP implements reliable connection setup, teardown, Explicit Congestion Notification (ECN), congestion control, and feature n ...
(DCCP) and
TCP Friendly Rate Control {{Short description, Congestion control mechanism in computer networks
TCP-Friendly Rate Control (TFRC) is a congestion control mechanism designed for unicast flows operating in an Internet environment and competing with TCP traffic. The goal is t ...
(TFRC).
She received the
IEEE Internet Award
IEEE Internet Award is a Technical Field Award established by the IEEE in June 1999. The award is sponsored by Nokia Corporation. It may be presented annually to an individual or up to three recipients, for exceptional contributions to the ad ...
in 2005 and the ACM
SIGCOMM Award The annual SIGCOMM Award for Lifetime Contribution recognizes lifetime contribution to the field of communication networks.
The award is presented in the annual SIGCOMM Technical Conference.
SIGCOMM is the Association for Computing Machinery (ACM) ...
in 2007 for her contributions to congestion control. She has been involved in the
Internet Architecture Board
The Internet Architecture Board (IAB) is a committee of the Internet Engineering Task Force (IETF) and an advisory body of the Internet Society (ISOC). Its responsibilities include architectural oversight of IETF activities, Internet Standards ...
, and was in 2007 one of the top-ten most cited researchers in computer science.
Awards
* 2007 -
SIGCOMM
SIGCOMM is the Association for Computing Machinery's Special Interest Group on Data Communications, which specializes in the field of communication and computer networks. It is also the name of an annual 'flagship' conference, organized by SIGCOMM ...
Award from the
ACM
ACM or A.C.M. may refer to:
Aviation
* AGM-129 ACM, 1990–2012 USAF cruise missile
* Air chief marshal
* Air combat manoeuvring or dogfighting
* Air cycle machine
* IATA airport code for Arica Airport in Amazonas Department, Colombia
Computing
...
Special Interest Group on Data Communications. Recognized as most prestigious award to a scientist in computer networking.
*
IEEE Communications Society
The Institute of Electrical and Electronics Engineers (IEEE) is an American 501(c)(3) public charity professional organization for electrical engineering, electronics engineering, and other related disciplines.
The IEEE has a corporate office i ...
's William R. Bennett Prize Paper Award for "Difficulties in Simulating the Internet", by Floyd and Vern Paxson
Personal life and death
Floyd's father
Edwin
The name Edwin means "wealth-friend". It comes from (wealth, good fortune) and (friend). Thus the Old English form is Ēadwine, a name widely attested in early medieval England. Edwina is the feminine form of the name.
Notable people and char ...
was a mathematician at the
University of Virginia
The University of Virginia (UVA) is a Public university#United States, public research university in Charlottesville, Virginia, United States. It was founded in 1819 by Thomas Jefferson and contains his The Lawn, Academical Village, a World H ...
. Floyd was married to Carole Leita.
Floyd died at the age of 69 on August 25, 2019, in Berkeley, California, from gallbladder cancer that had metastasized.
Selected notable papers
* S. Floyd and V. Jacobson, "Random Early Detection Gateways for Congestion Avoidance", ''
IEEE/ACM Transactions on Networking
''IEEE/ACM Transactions on Networking'' is a bimonthly peer-reviewed scientific journal covering communication networks. It is published by the IEEE Communications Society, the IEEE Computer Society, and the ACM Special Interest Group on Data Comm ...
'' (1993)
* S. Floyd and K. Fall, "Promoting the Use of End-to-End Congestion Control in the Internet", ''
IEEE/ACM Transactions on Networking
''IEEE/ACM Transactions on Networking'' is a bimonthly peer-reviewed scientific journal covering communication networks. It is published by the IEEE Communications Society, the IEEE Computer Society, and the ACM Special Interest Group on Data Comm ...
'' (1993)
* V. Paxson and S. Floyd, "Wide Area Traffic: The Failure of Poisson Modeling", ''
IEEE/ACM Transactions on Networking
''IEEE/ACM Transactions on Networking'' is a bimonthly peer-reviewed scientific journal covering communication networks. It is published by the IEEE Communications Society, the IEEE Computer Society, and the ACM Special Interest Group on Data Comm ...
'' (1995)
* M. Mathis, J. Mahdavi and S Floyd, A Romanow, "TCP Selective Acknowledgement Options", RFC 2018 (1996)
* S. Floyd and V. Paxson, "Why We Don't Know How to Simulate the Internet", Dec. 1997, Proceedings of the 1997 Winter Simulation Conference. Re-written as "Difficulties in Simulating the Internet", ''
IEEE/ACM Transactions on Networking
''IEEE/ACM Transactions on Networking'' is a bimonthly peer-reviewed scientific journal covering communication networks. It is published by the IEEE Communications Society, the IEEE Computer Society, and the ACM Special Interest Group on Data Comm ...
'', vol. 9, no. 4 (August 2001). Winner of the
IEEE Communications Society
The Institute of Electrical and Electronics Engineers (IEEE) is an American 501(c)(3) public charity professional organization for electrical engineering, electronics engineering, and other related disciplines.
The IEEE has a corporate office i ...