What's New

I am looking for a new PhD student and research assistant to work on the DARPA-funded Social media in strategic communication project. If you are interested in the analysis of social networks, please email me.

What Happens when HTTP Adaptive Streaming Players Compete for Bandwidth?, with Saamer Akhshabi, Lakshmi Ananthakrishnan and Ali Begen. At the ACM SIGMM NOSSDAV conference, June 2012.

GENESIS: An agent-based model of interdomain network formation, traffic flow and economics, with Aemen Lodhi and Amogh Dhamdhere. At the IEEE INFOCOM conference, March 2012.

I helped organize the 2nd Workshop on Internet Economics, at CAIDA (jointly with k.Claffy).

The Evolution of Layered Protocol Stacks Leads to an Hourglass-Shaped Architecture, with Saamer Akhshabi. At the ACM SIGCOMM conference, August 2011. See also the tech-report with some more results. Presentation slides (in pptx format). Presentation video stream (requires ACM DL membership).

Our research in the detection of traffic shaping and traffic discrimination (ShaperProbe and DiffProbe, respectively) has won the best-research award in the FCC Open Internet Challenge (shared with ICSI's NetAlyzr).
The paper that describes ShaperProbe has appeared at the ACM Internet Measurement Confeence, October 2011.

Twelve Years in the Evolution of the Internet Ecosystem, with Amogh Dhamdhere. At the ACM/IEEE Transactions on Networking, 2011.

Future Internet Architecture: Clean-Slate Versus Evolutionary Research, an open debate with Jennifer Rexford. At the Communications of the ACM (CACM), September 2010.

Who I am, What I do. On a similar tone, how do you distinguish a researcher from a salesman?

Education

• Ph.D., University of Wisconsin-Madison December 2000
  Research advisor: Parmesh Ramanathan
• M.S., University of Rochester May 1996
Research advisor: Eby Friedman
• B.Eng., Technical University of Crete June 1995
Research advisor: Apostolos Dollas

Teaching

• CS 8803-NS: Network Science: Methods and Applications (Fall'09)
• CS 7270: Internet applications and services (Spring'12, Spring'11, Spring'09, Fall'07)
• In Fall'08, I co-taught a graduate course on Networks in Systems Biology together with Prof. Todd Streelman from the School of Biology.

• CS 6250: Advanced Computer Networks (Fall'06, Fall'02)
• CS 7260: Internetworking Architectures and Protocols (Spring'03)
• CS 8803: Experimental Performance Evaluation of Computer Systems and Networks (Spring'05)
• CS 8803: Network Measurements (Fall'03)
• CS 4270: Internet Lab (Fall'11, Fall'10, Fall'08, Spring'08, Spring'07)
• CS 4251: Computer Networks II (Fall'04, Spring'04)
• CS 3251: Computer Networks I (Fall'05)
• CS 2200: Systems and Networks (Spring'06)

Research

Ongoing Research Projects in Computer Networking

• Economics of Internet peering
• A theory for the evolution of the Internet architecture
• Network inference and diagnosis of performance problems (Project Pythia)
• Adaptive video streaming over HTTP

Ongoing Research Projects in Network Science

• Spheres of influence in social media (social science)
• Network-based analysis of climate models (climate science)
• A network-based explanation for the developmental hourglass (biology)
• The structural network of major depression (brain science)

Public-domain software

• ShaperProbe: Detect if your ISP is rate-limiting your traffic
• DiffProbe: Detect if your ISP is giving lower priority to some of your network traffic
• Pathload2: Measure the available bandwidth of your Internet connection (using M-Lab servers)
• Pathrate, Pathload and ABget (bandwidth estimation tools)

Previous Research Projects

• The scalability of interdomain Internet routing (View this page in Romanian courtesy of azoft)
• Intelligent route control and performance-based routing
• Router buffer sizing
• Network bandwidth estimation
• Proportional differentiated services

Advisees

• Demetris Antoniades (since Feb'12, PostDoc)
• Partha Kanuparthy (since Jan'07, PhD program)
• Aemen Lodhi (since Aug'09, PhD program)
• Saamer Akhshabi (since Aug'09, PhD program)
• Ilias Foudalis (since Aug'10, PhD program)

Former PhD advisees:

• Amogh Dhamdhere (graduated in May'09, now at the CAIDA research center)
• Ravi Prasad (graduated in December'07, now at Cisco Systems)
• Ruomei Gao (co-advised with Ellen Zegura, graduated in August'07, now at Akamai)
• Manish Jain (graduated in December'06, now at Akamai)
• Yong Zhu (co-advised with Mostafa Ammar, graduated in August'06, now at Amazon)
• Qi He (co-advised with Mostafa Ammar, graduated in August'05, now at Yahoo!)

Funding (recently)

• DARPA,
  Social Media in Strategic Communication,
  February 2012 to February 2015.

• US Department of Energy (Office of Science),
  Advanced Performance Modeling with Combined Passive and Active Monitoring,
  January 2012 to January 2015.

• US Department of Energy (Office of Science),
  Validation and quantification of uncertainty in coupled climate models using network analysis,
  September 2011 to August 2014.

• Google Inc,
  "Peering Disputes Between Internet Service, Network & Content Providers",
  August 2011.

• US Department of Energy (Office of Science),
  Detection, Localization and Diagnosis of Performance Problems using perfSONAR,
  September 2010 to August 2013.

• Cisco Systems Inc,
  "Adaptive Video Streaming over HTTP",
  September 2010.

• National Science Foundation,
  "NetSE: The economics of transit and peering interconnections in the Internet",
  August 2010 to August 2013.

• Cisco Systems Inc,
  "The Economics of Interdomain Internet Connectivity",
  October 2009.

• Google Inc,
  "Detection, classification and localization of network neutrality violations using differential probing",
  April 2009.

• National Science Foundation,
  "NECO: Towards a Theory of Network Evolution",
  September 2008 to September 2011.

Professional Service (incomplete)

• ACM/IEEE Transactions on Networking, Editor
• ACM CoNEXT 2011, TPC Co-Chair
• USENIX/ACM IMC 2007, TPC Co-Chair
• ACM HotNets 2007, General Chair
• ACM Computer Communication Review (CCR), Editor (2006-2008?)
• ACM SIGCOMM 2011, 2007, 2006, 2004, TPC member
• ACM CoNEXT 2010, TPC member
• ACM SIGMETRICS 2007, 2006, TPC member
• IEEE INFOCOM 2009, 2008, 2007, 2006, 2005, 2004, 2002, TPC member
• ACM IMC 2005, 2004, TPC member
• PAM (Passive & Active Measurement) 2005, Program chair (and member of the Steering Committee 2005-2007)
• Bandwidth Estimation workshop 2003, Program co-chair