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Jonathan Ledlie

Senior Researcher, Networked Systems
Cambridge, US

Background

I joined Nokia Research in September 2007 and am based at the Nokia Research Center in Cambridge, US.

Before joining NRCC, I completed my PhD in Computer Science a few miles up the Charles River at Harvard, where Margo Seltzer was my advisor. My thesis examined how Network Coordinates perform in live, distributed environments. At Harvard, I also worked on file systems, distributed systems, and other operating systems-related topics. More details are available on my Harvard page and on my Network Coordinate research page.

At Nokia, my goals are to apply what I know about wired distributed systems to wireless systems, to build cool, useful systems that bridge devices and networked applications, and to take advantage of this near one-to-one mapping between individuals and these incredible gadgets we typically call "mobile phones."

Professional Activities

Current Software

  • Molé: Mobile Organic Localization Engine, a Qt-based organic indoor positioning system.
  • Asterisk::FastAGI::Site and Tangaza, an open source library for quickly building Asterisk-driven, programmable IVRs, and a spoken message group communications tool.

Previous Software

  • Pyxida, an open source network coordinate library (currently used in the popular Azureus and Vuze BitTorrent clients)
  • Hourglass/SBON, a distributed streaming database designed for smart in-network service placement.
  • Damelo! An Explicitly Co-Locating Web Cache File System.
  • An early version of the New York Times user login and authentication system.

Current Interns

  • None

Previous Interns

  • Jay Chen (NYU)
  • Billy Odero (U. of Nairobi, now at NRC/Nairobi)
  • Ryan Newton (MIT CSAIL)
  • Brian Omwenga (MIT Tech and Policy, now at NRC/Nairobi)
  • Matt Tierney (Harvard Undergraduate, now at NYU CS)

Classes Taught and Advised

Research Interests

  • Experimental large-scale and mobile distributed systems
  • Information and Communication Technology for Development (ICTD)

Research Projects

Current Projects

Past Projects

Conferences

Publications

Journal Publications

  • Jonathan Ledlie, Billy Odero, Einat Minkov, Imre Kiss, Joseph Polifroni, Crowd Translator: On Building Localized Speech Recognizers through Micropayments, SIGOPS Operating Systems Review, Volume 43, Issue 4, 2009.

Conference Publications

  • Jonathan Ledlie, Jun-geun Park, Dorothy Curtis, André Cavalcante, Leonardo Camara, Afonso Costa, and Robson Vieira, Molé: a Large-Scale, User-Generated Positioning Engine, In Proceedings of the International Conference on Indoor Positioning and Indoor Navigation (IPIN), Guimarães, Portugal, September 2011 (pdf, talk) (Best Paper Award).
  • Jun-geun Park, Dorothy Curtis, Seth Teller, Jonathan Ledlie, Implications of Device Diversity for Organic Localization, In Proceedings of IEEE INFOCOM 2011, Shanghai, China, April 2011 (pdf).
  • Jay Chen, Russell Power, Lakshmi Subramanian, Jonathan Ledlie, Design and Implementation of Offline Education Web Portals, In Proceedings of the 20th World Wide Web Conference (WWW), Web for Emerging Regions Track, Hyderabad, India, March 2011 (pdf).
  • Thom Haddow, Sing Wang Ho, Jonathan Ledlie, Cristian Lumezanu, Moez Draief, and Peter Pietzuch, On the Feasibility of Bandwidth Detouring on the Internet, In Proceedings of Passive and Active Measurement Conference (PAM), Atlanta, GA, March 2011 (pdf).
  • Billy Odero, Brian Omwenga, Pauline Githinji, Mokeira Masita-Mwangi, and Jonathan Ledlie, Tangaza: Frugal Group Messaging through Speech and Text, In Proceedings of Computing for Development (DEV), London, England, December 2010 (pdf).
  • Einat Minkov, Ben Charrow, Jonathan Ledlie, Seth Teller, and Tommi Jaakkola, Collaborative Future Event Recommendation, In Proceedings of CIKM, Toronto, Canada, October 2010 (pdf).
  • Jun-geun Park, Ben Charrow, Dorothy Curtis, Jonathan Battat, Einat Minkov, Jamey Hicks, Seth Teller, Jonathan Ledlie, Growing an Organic Indoor Location System, In Proceedings of the Eighth International Conference of Mobile Systems, Applications, and Services (MobiSys), San Francisco, CA, June 2010 (pdf).
  • Jonathan Ledlie, Paul Gardner, and Margo Seltzer, Network Coordinates in the Wild, In Proceedings of the Fourth USENIX Symposium on Network Systems Design and Implementation (NSDI), Cambridge, MA, April 2007 (pdf, tech report, html).
  • Ian Rose, Rohan Murty, Peter Pietzuch, Jonathan Ledlie, Mema Roussopoulos, and Matt Welsh, Cobra: Content-based Filtering and Aggregation of Blogs and RSS Feeds, In Proceedings of the Fourth USENIX Symposium on Network Systems Design and Implementation (NSDI), Cambridge, MA, April 2007 (pdf).
  • Jonathan Ledlie, Peter Pietzuch, and Margo Seltzer, Stable and Accurate Network Coordinates, In Proceedings of ICDCS 2006, Lisbon, Portugal, July 2006 (pdf, tr).
  • Peter Pietzuch, Jonathan Ledlie, Jeffrey Shneidman, Mema Roussopoulos, Matt Welsh, and Margo Seltzer, Network-Aware Operator Placement for Stream-Processing Systems, In Proceedings of the 22nd International Conference on Data Engineering (ICDE'06), Atlanta, GA, April 2006 (pdf, link).
  • Jonathan Ledlie and Margo Seltzer, Distributed, Secure Load Balancing with Skew, Heterogeneity, and Churn, In Proceedings of IEEE INFOCOM 2005, March 2005 (pdf).
  • Daniel Ellard, Jonathan Ledlie, Pia Malkani, Margo Seltzer, Passive NFS Tracing of Email and Research Workloads In Proceedings of the Second Annual USENIX File and Storage Technologies Conference, San Francisco, CA, March 2003 (pdf, link)

Workshop Publications

  • Johannes Schmid, Dorothy Curtis, Tobias Gädeke, Jonathan Ledlie, Improving Sparse Organic WiFi Localization with Inertial Sensors, In Proceedings of the Workshop on Positioning, Navigation, and Communication (WPNC), Dresden, Germany, March 2012.
  • Jonathan Ledlie, Huzzah for my thing: Evaluating a Pilot of a Mobile Service in Kenya, In Proceedings of Qual Meets Quant (QMQ), London, England, December 2010 (pdf).
  • Jonathan Ledlie, Billy Odero, Einat Minkov, Imre Kiss, Joseph Polifroni, Crowd Translator: On Building Localized Speech Recognizers through Micropayments, In Proceedings of Networked Systems for Developing Regions (NSDR), Big Sky, Montana, October 2009 (pdf, ppt).
  • Jonathan Ledlie, Billy Odero, and Nathan Eagle, Including Local Entrepreneurs in ICT4D, In Proceedings of the CCC Workshop on Computer Science and Global Development, Berkeley, CA, August 2009 (pdf).
  • Sing Wang Ho, Thom Haddow, Jonathan Ledlie, Moez Draief, and Peter Pietzuch, Deconstructing Internet Paths: An Overlay for AS-Level Detour Routing, In Proceedings of the Eighth International Workshop on Peer-to-Peer Systems (IPTPS), Boston, MA. April, 2009 (pdf).
  • Jonathan Ledlie, Nathan Eagle, Matthew Tierney, Mark Adler, Harri Hansen, and Jamey Hicks, Mosoko: a mobile marketplace for developing regions, In Proceedings of Designing Interactive Systems for Communities in the Developing World, Cape Town, South Africa, February 2008 (link,pdf).
  • Jonathan Ledlie, Peter Pietzuch, Michael Mitzenmacher, and Margo Seltzer, Wired Geometric Routing, In Proceedings of IPTPS, Bellevue, WA, February 2007 (pdf).
  • Peter Pietzuch, Jonathan Ledlie, Michael Mitzenmacher, and Margo Seltzer, Network-Aware Overlays with Network Coordinates, In Proceedings of IWDDS, Lisbon, Portugal, July 2006 (pdf, html).
  • Peter Pietzuch, Jonathan Ledlie, and Margo Seltzer, Supporting Network Coordinates on PlanetLab, In Proceedings of WORLDS, San Francisco, CA, December 2005 (pdf, html)
  • Jonathan Ledlie, Chaki Ng, David Holland, Kiran-Kumar Muniswamy-Reddy, Uri Braun, and Margo Seltzer, Provenance-Aware Sensor Data Storage, In Proceedings of NetDB, Tokyo, Japan, April 2005 (pdf, link, html).
  • Peter Pietzuch, Jeffrey Shneidman, Jonathan Ledlie, Matt Welsh, Margo Seltzer, and Mema Roussopoulos, Evaluating DHT-Based Service Placement for Stream-Based Overlays, In Proceedings of IPTPS, Ithaca, NY. February 2005 (pdf, link).
  • Jonathan Ledlie, Jeff Shneidman, Matt Welsh, Mema Roussopoulos, and Margo Seltzer, Open Problems in Data Collection Networks, In Proceedings of European SIGOPS, September 2004 (pdf).
  • Jonathan Ledlie, Jeff Shneidman, Margo Seltzer, and John Huth, Scooped, Again, In Proceedings of IPTPS, Berkeley, CA. February 2003 (pdf).
  • Jonathan Ledlie, Jacob Taylor, Laura Serban, and Margo Seltzer, Self-Organization in Peer-to-Peer Systems, In Proceedings of European SIGOPS, September 2002 (pdf).

Theses

  • Jonathan Ledlie, A Locality-Aware Approach to Distributed Systems, Ph.D. Thesis, Harvard University, September 2007 (compact, full, abstract, title+abstract).
  • Jonathan Ledlie, Dáamelo! An Explicitly Co-Locating Web Cache File System, Master's Thesis at the University of Wisconsin-Madison, December 2000 (pdf).

Technical Reports and Non-Refereed Publications

  • Jonathan Ledlie, Simple, On-Device Positioning using Compressed Fingerprint Archives, Nokia Research Technical Report NRC-TR-2010-002, July 2010 (pdf).
  • Seth Teller, Jonathan Battat, Ben Charrow, Dorothy Curtis, Russell Ryan, Jonathan Ledlie, Jamey Hicks, Organic Indoor Location Discovery, MIT CSAIL Technical Report TR-2008-075, December 2008 (pdf).
  • Jonathan Ledlie, File System Support for Low-Bandwidth Thumbnails, Nokia Research Technical Report NRC-TR-2008-004, May 2008 (pdf).
  • Jonathan Ledlie, Peter Pietzuch, Margo Seltzer, Proxy Network Coordinates, Imperial College London Department of Computing Technical Report, February 2008 (pdf).
  • Margo Seltzer, Kiran-Kumar Muniswamy-Reddy, David Holland, Uri Braun, and Jonathan Ledlie, Provenance-Aware Storage Systems, Harvard University Computer Science Technical Report TR-18-05, July 2005 (pdf).
  • Jeff Shneidman, Peter Pietzuch, Jonathan Ledlie, Mema Roussopoulos, Margo Seltzer, Matt Welsh, Hourglass: An Infrastructure for Connecting Sensor Networks and Applications , Harvard University Computer Science Technical Report TR-21-04, May 2004 (pdf).
  • Jonathan Ledlie, Jeff Shneidman, Matthew Amis, Michael Mitzenmacher, and Margo Seltzer, Reliability- and Capacity-based Selection in Distributed Hash Tables, Harvard University Computer Science Technical Report, September 2003 (pdf).
  • Daniel Ellard, Jonathan Ledlie, and Margo Seltzer, The Utility of File Names, Harvard University Computer Science Technical Report TR-05-03, March 2003 (pdf).
  • Daniel Ellard, Jonathan Ledlie, Pia Malkani, and Margo Seltzer, Everything You Always Wanted to Know About NFS Trace Analysis, But Were Afraid to Ask, Harvard University Computer Science Technical Report TR-06-02, June 2002 (pdf).
  • Jonathan Ledlie, Laura Serban, and Dafina Toncheva, Scaling Filename Queries in a Large-Scale Distributed File System, Harvard University Technical Report TR-03-02, January 2002 (link, pdf).
  • Matthew McCormick, Jonathan Ledlie, and Omer Zaki, Adaptively Scheduling Processes on a Simultaneous Multithreading Processor, University of Wisconsin-Madison Computer Architecture Project, December 2000 (pdf).
  • Justin Forrester and Jonathan Ledlie, X-Join and the Benefits of Free Work, University of Wisconsin-Madison Databases Project, May 2000 (pdf).

Patents

  • Jonathan Ledlie, Method and Apparatus for Private Collaborative Filtering, Under submission (US 13/315801), December 9, 2011.
  • Jonathan Ledlie, Methods, Apparatuses, and Computer Program Products for Providing Automatic Maintenance of a Geopositioning System, Under submission (US 13/233905), September 15, 2011.
  • Jonathan Ledlie, Method and Apparatus for Prefetching Location-based Data while Maintaining User Privacy, Under submission (US 13/035307), Feburary 25, 2011.
  • Jonathan Ledlie and Jun-geun Park,
    Methods, Apparatuses, and Computer Program Products for Providing a Private and Efficient Geolocation System, Under submission (US 13/028742), February 16, 2011.
  • Jonathan Ledlie, Leo Karkkainen, Pentti Valtteri Niemi, Method and Apparatus for Context-based on Spatial Trails, Under submission (US 12/980864), December 29, 2010.
  • Jonathan Ledlie, Method and Apparatus for Fetching Data Based on Network Conditions, Under submission (US 12/906711), October 2010.
  • Cynthia Kuo, Quinn Jacobson, Jonathan Ledlie, Location-based CAPTCHAs for Map Data Collection and Verification, Under submission (US 61/367248), July 2010.
  • Jun-geun Park, Jonathan Ledlie, Ben Charrow, Jonathan Battat, Dorothy Curtis, Einat Minkov, Jamey Hicks, Seth Teller, Method and Apparatus for Constructing a User-Generated Geolocation System, Under submission, December 2009.
  • Jonathan Ledlie, Method and Apparatus for On-Device Positioning and Messaging Using Compressed Fingerprint Archives, Under submission, December 2009.
  • Jonathan Ledlie, Jamey Hicks, Seth Teller, Jonathan Battat, Ben Charrow, Dorothy Curtis, Method, Apparatus, and Computer Program Product for Facilitating Location Discovery, Under submission, November 2008.
  • Jonathan Ledlie, Method, Apparatus, and Computer Program Products for Providing an Audible Interface to Publish/Subscribe Service, Under submission, June 2008.