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Brad Petersen
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56 Everitt Lab
1406 W. Green St.
Urbana, IL 61801
Phone: (217) 244-6376
Fax: (217) 265-6499

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ECE students on Capitol Hill

ECE students on Capitol Hill

Seven Illinois students met with legislators in Washington, D.C., during the Congressional Visits Day last month.

Remembering Rene Cruz, an ECE alumnus and network innovator

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October 1, 2013

  • Early in his career, Cruz pioneered the area of information theory known as "network calculus" that addresses issues of flow in communication networks.
  • A 1980 Bronze Tablet honoree, Cruz went on to earn an Illinois doctorate. His 1987 dissertation laid the groundwork for the new field of network calculus.
  • Later in his career with the University of California, San Diego, Cruz focused on "broadband bonding" and "content-centric" networking. In 2004 he cofounded the network equipment manufacturer Mushroom Networks.

ECE lost a distinguished member of its community last summer with the untimely death, on June 29, of alumnus Rene L. Cruz (BSEE '80, PhD '87), a professor of electrical and computer engineering at the University of California, San Diego, who advanced the understanding and design of communication networks. Cruz was 53.

Rene L. Cruz (photo courtesy University of California, San Diego)
Rene L. Cruz (photo courtesy University of California, San Diego)
The son of ECE Emeritus Professor Jose B. Cruz (PhD '59) and wife Patricia, Rene Cruz was born and raised in Urbana and earned Bronze Tablet honors as an ECE undergraduate. After completing his master’s degree at MIT and working as a senior engineer at Stanford Telecommunications, he returned to Illinois for doctoral work with ECE Professor Bruce Hajek. Cruz’s 1987 dissertation laid the groundwork for his novel methodology of “network calculus,” which enabled engineers to ascertain bounds on delay and buffering requirements in networks.

After joining the UCSD faculty in 1987, Cruz refined his dissertation work into a tandem of articles for IEEE Transactions on Information Theory that appeared in 1991 and established the foundation for the new research field of network calculus.

“While we discussed several other research problems, he kept coming back to the problem of multiplexing and demultiplexing bursty data streams in an efficient way,” said Hajek. “That blossomed during his PhD work at Illinois. The first paper based on his thesis now has 2000 citations, and it essentially started a whole field of research.”

Hajek first met Cruz in 1979 when Cruz was assigned as a grader for Hajek’s course on probability, ECE 313. The two began a research collaboration during Cruz’s senior year which led to a journal publication. “I realized Rene was a special person from the time I met him for his unassuming personality combined with sharp perception and a ready laugh,” said Hajek.

Rene Cruz (right) and father Jose, an ECE emeritus professor, at Rene's 1987 PhD graduation on the Illinois campus. 'He was an easygoing fellow, very low key, humble,' said Jose Cruz. 'He liked simple things in life.' (photo courtesy Jose B. Cruz)
Rene Cruz (right) and father Jose, an ECE emeritus professor, at Rene's 1987 PhD graduation on the Illinois campus. 'He was an easygoing fellow, very low key, humble,' said Jose Cruz. 'He liked simple things in life.' (photo courtesy Jose B. Cruz)
“Rene always questioned why things were the way they were,” said Jose Cruz, now retired from his post as dean of engineering at Ohio State University. “He was research oriented in this sense, but more importantly he was able to come up with innovative ideas.”

In 2004 Cruz cofounded Mushroom Networks, whose products are based on his patented “broadband bonding” technology that enables network appliances to aggregate disparate Internet connections into a single high-speed service. At the time of his death, Cruz was the company’s chief science officer. “I’m very proud of his ability to create deep theoretical results and then demonstrate how these theories lead to very practical and useful devices and systems,” said the elder Cruz.

Cruz’s most recent research was in the emerging field of “content-centric networking,” an alternative to the current host-centric architecture of the Internet, which aims to reduce congestion and complexity while enhancing speed and security. Specifically, he was investigating algorithms to distribute the message forwarding function among network users so that each received the content relevant to him or her. “It’s unfortunate he won’t be able to develop this work further,” said Hajek. “I’ll miss discussing new ideas with Rene, and miss his cheerful presence.”

Rene Cruz’s pioneering work was recognized by the IEEE INFOCOMM Achievement Award (2009) for contributions to network calculus, the IEEE Communications Society Stephen O. Rice Prize in the Field of Communications Theory (2008), IEEE Fellow (2003), the NSF Presidential Young Investigator Award (1991), and many other honors and awards.

Cruz is survived by his parents, four siblings, wife Erin, two children, and two stepchildren. The Rene Cruz Memorial website hosted at UCSD provides more information and a link for donating to pancreatic cancer research in Cruz’s memory.

Editor's note: media inquiries should be directed to Brad Petersen, Director of Communications, at or (217) 244-6376.

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