Design and performance analysis of communication networks, with an emphasis on high speed wireless and optical systems, scheduling, routing, network calculus.
Professor Cruz's early work was on the analysis of information flow in communication networks. He is known for the development of a research area called "network calculus" for characterizing the flow of data through packet-switching networks, including the Internet. By analyzing the potential burstiness of traffic flows, the calculus identifies the possible delay of packets queuing up at various points in a network. Previous mathematical analyses of queuing delay were largely confined to statistical approaches that addressed only a single queue. The "traffic envelope," a key network-calculus concept, has been applied in a wider range of areas including performance-assessment of data-scheduling algorithms, in characterizations of traffic that crosses network boundaries, in connection with "Service Level Agreements" (SLAs) for billing in privately operated networks including frame-relay networks run by various telecommunication carriers, and in research aimed at better specifying quality-of-service (QoS) levels for network traffic flows.
Rene Cruz joined the UCSD faculty in 1987, after receiving his Ph.D. the same year from the University of Illinois at Urbana-Champaign (UIUC). He received his S.M.E.E. from MIT in 1982 (where he held a Vinton Hayes Fellowship in Communications), and his B.S.E.E. from UIUC in 1980. Cruz was an NSF Graduate Fellow from 1981-86. He received an NSF Presidential Young Investigator Award in 1991. He co-chaired the Technical Program Committee of the 2001 IEEE INFOCOM Conference, which is the annual joint conference of the IEEE Computer and Communication Societies. He was a general chair of the 2001 ACM SIGCOMM Conference, which was held on the UCSD campus. Cruz was elected a Fellow of the IEEE in January 2003.