A. Helmy's picture NOMADS group logo

Ahmed Helmy
Professor & Graduate Coordinator
Computer & Information Science & Engineering (CISE) Department
Founder and Director: Mobile Networking Laboratory (NOMADS group)
College of Engineering, University of Florida
Gainesville, FL 32611
email: helmy at ufl.edu

Select a project: MobiBench (New) - AWARE - MARS - ACQUIRE - M&M - STRESS - AQM-marking - VINT/NS - PIM

MobiBench

- Funded by NSF.
- To be updated ...

AWARE (Interest-Aware Delivery for Future Mobile Social Networks)

- Funded by NSF and Cisco.
- Please see publications on 'profile-cast', 'mining behavior', and 'co-clustering' to name a few.
- To be updated ...

MARS (Mobility Modeling and Resource Discovery in Ad hoc and Sensor Networks) (Completed)

M&M(Multicast-based Architecture for IP Mobility) (Completed)

  1. A. Helmy, M. Jaseemuddin, G. Bhaskara, "Multicast-based Mobility: A Novel Architecture for Efficient Micro-Mobility", IEEE Journal on Selected Areas in Communications (JSAC), Special Issue on All-IP Wireless Networks, Vol. 22, No. 4, pp. 677-690, May 2004.
  2. A. Helmy, "A Multicast-based Protocol for IP Mobility Support", ACM SIGCOMM Int'l Workshop on Networked Group Communication (NGC), November 2000 [ ppt] [Here is a library of topologies used for the simulations of M&M (NGC), in a format compatible with the network simulator (NS-2)].
  3. F. Bai, G. Bhaskara, A. Helmy, "Building the Blocks of Protocol Design and Analysis - Challenges and Lessons Learned from Case Studies on Mobile Ad hoc Routing and Micro-Mobility Protocols", ACM Computer Communications Review (CCR), Special issue on Science of Networking Design, Volume 34, Number 3, pp. 57 - 69, July 2004. [Acceptance rate: 15% of 40 submissions]
  4. G. Bhaskara, A. Helmy, "TCP over Micro Mobility Protocols: A Systematic Ripple Effect Analysis", IEEE Vehicular Technology Conf (VTC), Sept '04
  5. A. Helmy, "State Analysis and Aggregation Study for Multicast-based Micro Mobility", IEEE ICC, Vol. 5, pp. 3301-3306, May 2002. [Slides (.ppt)].

STRESS (Systematic Testing and Evaluation of Networking Protocols) (Completed)

  1. S. Begum, A. Helmy, S. Gupta, "Modeling the Interactions Between MAC and Higher Layers: A Systematic Approach to Generate High Level Scenarios from MAC Level Scenarios", ACM Transactions on Modeling and Computer Simulation (TOMACS). Accepted, to appear in Spring 2010.
  2. S. Begum, A. Helmy, S. Gupta, "Modeling and Test Generation for Worst-Case Performance Evaluation of MAC Protocols for Wireless Ad Hoc Networks", IEEE Int'l Symposium on Modelling, Analysis and Simulation of Computer and Telecommunication Systems (MASCOTS), full presentation, Sept. 2009.
  3. S. Begum, S. Gupta, A. Helmy, "Performance Analysis of Wireless MAC Protocols using a Search-based Framework", 15th IEEE Int'l Symposium on Modeling, Analysis and Simulation of Computer and Telecommunication Systems (MASCOTS), Oct. 2007.
  4. S. Ebrahimi, A. Helmy, S. Gupta, "TCP vs. TCP: a Systematic Study of Adverse Impact of Short-lived TCP Flows on Long-lived TCP Flows", IEEE INFOCOM, March 2005. [Earlier version as ACM SIGCOMM poster, August 2004. (Poster (pdf))]
  5. K. Seada, A. Helmy, S. Gupta, "A Framework for Systematic Evaluation of Multicast Congestion Control Protocols", IEEE Journal on Selected Areas in Communications (JSAC), Special issue on Protocol Design and Testing, Vol. 22, No. 10, Dec 2004. [Earlier version at IEEE GLOBECOM, Nov '02]
  6. A. Helmy, S. Gupta, D. Estrin, 'The STRESS Method for Boundary-point Performance Analysis of End-to-end Multicast Timer-Suppression Mechanisms', IEEE/ACM Transactions on Networking (ToN), Vol. 12, No. 1, pp. 44-58, February 2004. [Earlier version in FORTE/PSTV Oct 2000.]
  7. F. Bai, G. Bhaskara, A. Helmy, "Building the Blocks of Protocol Design and Analysis - Challenges and Lessons Learned from Case Studies on Mobile Ad hoc Routing and Micro-Mobility Protocols", ACM Computer Communications Review (CCR), Special issue on Science of Networking Design, Volume 34, Number 3, pp. 57 - 69, July 2004. [Acceptance rate: 15% of 40 submissions].
  8. A. Helmy, D. Estrin, S. Gupta, "Systematic Testing of Multicast Routing Protocols: Analysis of Forward and Backward Search Techniques", The 9th International Conference on Computer Communications and Networks (IEEE ICCCN 2000), pp. 590-597, October 2000. Abstract.
  9. S. Begum, M. Sharma, A. Helmy, S. Gupta, "Systematic Testing of Protocol Robustness: Case Studies on Mobile IP and MARS", Proceedings of the 25th annual IEEE conference on Local Computer Networks (LCN), pp. 369-380, Florida, November 2000. Abstract
  10. A. Helmy, D. Estrin, S. Gupta, "Fault-oriented Test Generation for Multicast Routing Protocol Design", Proceedings of Formal Description Techniques & Protocol Specification, Testing, and Verification (FORTE/PSTV), IFIP, Kluwer Academic Publication, Paris, France, p. 93-109, November 1998.

AQM-based Marking & Fairness (Completed)

  1. A. Das, D. Dutta, A. Helmy, A. Goel, J. Heidemann, "Low State Fairness: Lower Bounds and Practical Enforcement", IEEE INFOCOM, March 2005.
  2. A. Das, D. Dutta, A. Helmy, "A Low-state Packet Marking Framework for Approximate Fair Bandwidth Allocation", IEEE Communications Letters, Vol. 8, No. 9, pp. 588-590, Sept 2004.
  3. A. Das, D. Dutta, A. Helmy, "Fair Stateless Aggregate Marking using Active Queue Management Techniques", IEEE International Conference on Management of Multimedia Networks and Services (MMNS), pp. 211-223, October 2002. (Best Paper Award).

VINT/NS (The Virtual Internet Network Simulation & the Network Simulator NS-2) (Completed)

  1. L. Breslau, D. Estrin, K. Fall, S. Floyd, J. Heidemann, A. Helmy, P. Huang, S. McCanne, K. Varadhan, Y. Xu, H. Yu, "Advances in Network Simulation", IEEE Computer, vol. 33, No. 5, p. 59-67, May 2000. Abstract
  2. A. Helmy, D. Estrin, "Simulation-based `STRESS' Testing Case Study: A Multicast Routing Protocol", IEEE Sixth International Symposium on Modeling, Analysis and Simulation of Computer and Telecommunication Systems (MASCOTS), Montreal, Canada, July 1998. Abstract

PIM (The Protocol-Indepent Multicast Routing Protocol) (Completed)

  1. D. Estrin, M. Handley, A. Helmy, P. Huang, D. Thaler, " A Dynamic Bootstrap Mechanism for Rendezvous-based Multicast Routing", Proceedings of IEEE INFOCOM '99, New York, Vol. 3, pp. 1090-1098, March 1999. Abstract [Extended]
  2. D. Estrin, D. Farinacci, A. Helmy, D. Thaler, S. Deering, V. Jacobson, M. Handley, C. Liu, P. Sharma, L. Wei, "Protocol Independent Multicast - Sparse Mode (PIM-SM): Protocol Specification, Version 2", RFC 2362/2117 of the Internet Engineering Task Force (IETF), Inter-Domain Multicast Routing (IDMR), June 1998. [RFC2362]
  3. D. Estrin, D. Farinacci, A. Helmy, D. Thaler, S. Deering, V. Jacobson, M. Handley, C. Liu, P. Sharma, L. Wei, "Protocol Independent Multicast (PIM): Motivation and Architecture", Proposed RFC of the IETF/IDMR, October 1996. [.ps]
  4. D. Estrin, D. Farinacci, A. Helmy, V. Jacobson, L. Wei, "Protocol Independent Multicast - Dense Mode (PIM-DM): Protocol Specification", Proposed RFC of the IETF/IDMR, September 1996.


[Note: This page is being updated. Here are more up-to-date Key publications ]