Katia Obraczka


Address

Computer Engineering Department
Jack Baskin School of Engineering
University of California, Santa Cruz
1156 High Street
Santa Cruz, CA 95064
Office Location: 329 Baskin Center Voice: (831) 459-4308
Fax: (831) 459-4829
E-mail: katia@cse.ucsc.edu

I am an Assistant Professor at UC Santa Cruz in the Jack Baskin School of Engineering. My research and teaching interests include computer networks, distributed systems, Internet information systems, and operating systems.

I am currently working on projects in the areas of multicast routing for ad hoc networks, Internet measurements, making high-performance distributed computing applications network topology aware, congestion control for reliable multicast, and Internet object cache performance. For more details on this work, refer to the publications below.

I received my B.S. and M.S. in electrical and computer engineering from the Federal University of Rio de Janeiro. I received my M.S and Ph.D. in Computer Science from the University of Southern California in 1990 and 1994, respectively.


Courses taught at USC

Advanced Operating Systems (CS 555).

Special Topics on Wireless Networks and Mobile Computing (CS 599).

Introduction to Computer Networks (EE/CS 450).


Courses at UCSC

Computer Networks (CMPE 252).

Advanced Topics in Computer Engineering: Wireless and Mobile Networking (CMPE 293).


Publications and Projects

Internet Service Replication

This work focuses on efficient replication of services in wide-area, autonomously managed internets. The resulting replicator was implemented as part of the Harvest Resource Discovery System. For more information, check out the following publications:

"Evaluating the Performance of Flood-d: A Tool for Efficiently Replicating Internet Information Services", Katia Obraczka and Peter Danzig, IEEE JSAC, August 1997.

"A Tool for Massively Replicating Internet Archives: Design, Implementation and Experience", Katia Obraczka, Peter Danzig, Dante DeLucia, and Erh-Yuan Tsai, Proceedings of the 16th. International Conference on Distributed Computing Systems, May 1996.

"Finding Low-Diameter, Low Edge-Cost Networks", Katia Obraczka, Peter Danzig, Kitinon Wangpattanamongkol, Computer Science Department - University of Southern California - Tecnical Report, May 1997.

Massively Replicating Services in Wide Area Internetworks , Katia Obraczka, PhD dissertation, Computer Science Department, University of Southern California, December 1994.

Massively Replicating Services in Autonomously Managed, Wide-Area Internetworks , Katia Obraczka, Peter Danzig, and Dante DeLucia, Computer Science Department - University of Southern California - Tecnical Report No. 93-541.

Congestion Control for Internet Multicast

"Multicast Transport Mechanisms: A Survey and Taxonomy", Katia Obraczka, IEEE Communications Magazine, January 1998.

"Multicast Feedback Suppression Using Representatives", Dante DeLucia, Katia Obraczka, IEEE Infocom97.

"A Multicast Congestion Control Mechanism for Reliable Multicast", Dante DeLucia, Katia Obraczka, Proceedings of the IEEE ISCC'98 (also Computer Science Department - University of Southern California - Technical Report 97-658), August 1997.

"Congestion Control Performance of a Reliable Multicast Protocol", Dante DeLucia, Katia Obraczka, Proceedings of the IEEE ICNP'98, August 1998.

"A Multicast Congestion Control Mechanism Using Representatives", Dante DeLucia, Katia Obraczka, Computer Science Department - University of Southern California - Technical Report 97-651, May 1997.

"Multicast Feedback Suppression Using Representatives", Dante DeLucia, Katia Obraczka, Computer Science Department - University of Southern California - Technical Report No. 96-638, June 1996.


Internet Measurements

We implemented a tool, topology-d that evolved from the Harvest replicator. Topology-d periodically estimates available network bandwidth and delay among participating sites. Based on these estimates, topology-d computes a fault-tolerant, low communication cost logical topology connecting participating sites. Click here for the current topology-d distribution.

"The Performance of a Service for Network-Aware Applications", Katia Obraczka and Grig Gheorghiu, Proceedings of the ACM Sigmetrics SPDT'98; also Computer Science Department - University of Southern California - Technical Report 97-660, October 1997.

"Network Latency Metrics for Server Proximity", Katia Obraczka and Fabio Silva, Proceedings of the IEEE Globecom 2000, December 2000.


Web Caching

I have also collaborated with Peter Danzig on ways of improving Web caching performance. Click here for more information on the techniques and the corresponding prototypes we have developped.

"World Wide Web Caching: Trends and Techniques", Greg Barish and Katia Obraczka, to appear at the IEEE Communications Magazine Internet Technology Series, May 2000.

"Scalable, Highly-Available Web Caching", Katia Obraczka, Peter Danzig, Solos Arthachinda and Muhammad Yousuf Computer Science Department - University of Southern California - Technical Report 97-662, December 1997.


Wireless Networks and Mobile Computing

I am interested in multicast routing in the context of wireless, multi-hop ad-hoc networks. For more information on our IMAHN project (including publications) click here .

I am also working on a new network layer protocol for communication among devices with varying power, processing, and communication capabilities, ranging from conventional general purpose desktops and laptops to specialized sensors and actuators.

"A Lightweight Protocol for Interconnecting Heterogeneous Devices in Dynamic Environments", Kevin Almeroth, Katia Obraczka and Dante De Lucia, Proceedings of the IEEE ICMCS'99, June 1999.


"FLIP: A Flexible Protocol for Communication Between Heterogeneous Devices", Ignacio Solis, Katia Obraczka and Julio Marcos Proceedings of the IEEE ISCC 2001, July 2001.

Performance of Transport and Above Protocols

"Performance of a Reliable, Request-Response Transport Protocol", Nader Salehi, Katia Obraczka and Clifford Neuman, IEEE ISCC'99, July 1999.

"Modeling the Performance of HTTP Over Several Transport Protocols", John Heidemann, Katia Obraczka, and Joe Touch, IEEE/ACM Transactions on Networking, vol. 5, number 5, October 1997.

"Analysis of HTTP Performance", Joe Touch, John Heidemann, and Katia Obraczka. Released as web page http://www.isi.edu/lsam/ib/http-perf/, June, 1996.

Resource Discovery

Internet Resource Discovery Services , Katia Obraczka, Peter Danzig, and Shih-Hao Li, IEEE Computer Magazine, Vol. 26, Number 5, September 1993, pp. 8-22.

Distributed Indexing of Autonomous Internet Services , Peter Danzig, Katia Obraczka, and Shih-Hao Li, Journal of Computing Systems, Vol. 5, Number 4, Fall 1992.

Distributed Indexing: A Scalable Mechanism for Distributed Information Retrieval , Peter Danzig, Katia Obraczka, John Noll, and Jong-Suk Ahn, Proceedings of the 14th. Annual Internation ACM-SIGIR, October 1991, pp. 220-229.1991 ACM SIGIR.


The Domain Name System

An Analysis of Wide-Area Name Server Traffic: A Study of the Domain Name System , Peter Danzig, Katia Obraczka, and Anant Kumar, Proceedings of the ACM SIGCOM'92, August 1992.


Inter-Domain Policy Routing

Connectivity Database Overhead for Inter-Domain Policy Routing, Katia Obraczka and Deborah Estrin, Proceedings of the IEEE Infocom'91, April 1991.


Other Publications

Evaluation of a RISC Architecture for Modula-2, Katia Obraczka, M.Sc. Thesis, Federal University of Rio de Janeiro, March 1987.