Eric Freudenthal

Assistant Professor University of Texas at El Paso Computer Science Department Office: Room 202a Lab: Room 320 234 Hawthorne St.(# 36 on the campus map) El Paso, TX 79902 shared fax: 915/747-5030 tethered: 915/747-6954 efreudenthal @ utep.edu wireless: 917/279-6208

• 3-4PM on Tuesdays
• 6-7PM on Thursdays
• Let me know of your intention to visit (send email) since I will depart if students are neither present nor expected.
• Please send email suggesting alternate times if this schedule is not convenient.

Scheduling a meeting: Since my public calendar is available online, you can select and propose a mutually convenient meeting via email. It's particularly convenient if this invitation is generated by a calendar tool.

• For Outlook: send invitations to efreudenthal@utep.edu
• For Google Calender: send invitations to eric@freudenthal.net

I encourage your invitations to include (1) your name, (2) preferred email address, (3) phone number and (4) reason for the meeting. It's also a good idea to suggest alternate times.

Research

I enjoy designing systems that achieve robustness through adaptation to changing constraints. My recent focus has been in decentralized systems, including mechanisms for expressing and enforcing security relationships among mutually distrustful administrative domains, securely deploying mobile agents, and the efficient dissemination of on-line content. My background also includes electrical design, architecture, interprocess coordination, and computer vision.

My current research is described on multiple web sites.

• Systems and security: My active systems and security research efforts are described on the Robust Autonomic Systems Research Group's web site.
• Education research: I have recently become engaged in engineering and computer-science education research.

  Educational projects:

  • An Introduction ot Computational Systems: This project, which is supported by NSF CCLI and CPATH grants, is investigating engaging CS curricula that simultaneously introduces students to programming and reinforces understandings of mathematical principles.
  • Introduction to C and Computer Organization is examining effective approaches for simultaneously introducing students already familiar with Java to C, machine language, and computer organization.
  • Algorithms Exposed is examining effective pedagogy for teaching algorithms in an engaging and memorable manner.

Many of my publications are listed on my publications page.

Significant Prior Efforts

I collaborated with Michael Freedman and David Mazieres in the development of CoralCDN, a locality-sensitive self-organizing content dissemination network. Coral's indices are stored in a hierarchy of interleaved distributed hash tables that share the same name space. Constituent hash tables represent nested ranges of network locality constraints, and all nodes are members of a global hash table with no locality constraints. A single Coral node represents the same hash bucket in multiple hash tables, and searches prefer to search tables with better network connectivity, and only revert to tables with inferior connectivity when necessary.

Echoing characteristics of the Ultracomputer's combining network, Coral dynamically replicates data near to clients, thereby minimizing hot-spot congestion. While Coral is not robust to security challenges, it is expected to to provide high performance even in the presence of partial system failure.

More information on this project is available on the Coral home page.

• Security Infrastructure for Decentralized Systems
  2000-2004, I collaborated with Vijay Karamcheti in an investigation of security needs of systems deployed into dynamic environments that span a large number of administrative domains.

  The deployment of and communication among dynamically deployed software agents requires the establishment of sustained authorizing trust relationships between agents and systems that host them, and other agents with whom they interact. Existing component-based frameworks (e.g. J2EE and grid) do not offer appropriate security guarantees for coalition systems that span multiple mutually-distrustful administrative domains.

  We developed a deployment substrate for mobile agents called DisCo and a decentralized role-based access control system called dRBAC that incorporated mechanisms for increasing the expressiveness of transitive credentials to include trust metrics. We also investigated techniques for aggregating trust along multiple independent authorization paths.

  An extended summary of this work is available onlne.
  
  

• Coordination for Shared Memory Systems
  As a graduate student supervised by Allan Gottlieb, I investigated support for scalable inter-process coordination on shared-memory MIMD systems. My contributions include detection and analysis of problems in architectures that implmement hardware combining. I propose design modifications that significantly mitigate these effects. I also have contributed centralized algorithms that have lower synchronization latency than those previously known (and superior to commonly used alternatives).

  Hot spot contention in combining networks investigated in my research has analogues in other networked systems. I anticipate that variants of the techniques I propose to mitigate the impact of hot spot congestion on both hot spot and non hot spot traffic can be generalized to other networked systems.

  A more complete summary of my dissertation reseaerch is available online: http://rlab.cs.utep.edu/~freudent/thesisSummary.html. Additional details are available in Technical Report TR2003-849. This report and my full dissertation can be downloaded from the NYU Computer Science Department web site.
  
  

• Image Recognition
  I investigated automatic target recognition in imagery collected using synthetic aperture radar, participating in several research projects associated with DARPA's MSTAR model-based vision research program and the AFRL's Model Based Vision Lab. I collaborated with Lockheed-Martin, Veridian-Erim, Diamondback Vision, and the University of Cincinatti on the MEP4 project that investigates identification of partially occluded targets. I also collaborated with Alphatech Corporation and SAIC to investigate the inherent complexity of the SAR ATR problem. This project was awarded a second phase STTR.

  In collaboration with Ben Goldberg and Davi Geiger, I organized the NYU Recognition Lab, computational resource available for research in computer vision as applied to automatic target recognition. The equipment for this lab was purchased under a grant from the AFOSR's DURIP program.

  The DARPA-sponsored MSTAR effort engaged approximately one hundred scientists at ten institutions in the construction of an experimental model-based system to detect and identify targets in SAR (synthetic aperture RADAR) imagery. My research contributions included algorithms for efficient registration and object identification, the development of a parallelized hypothesis evaluation and refinement executive, and optimizing template selection algorithms.

Content from prior versions of this web page.