Ahmed Helmy's Publications

Publications By Theme

Wireless Mobile Ad Hoc and Sensor Networks

• Mobility Modeling and Analysis:
  
  
  • The IMPORTANT Framework for Mobility Modeling and Analysis:
    • F. Bai, N. Sadagopan, A. Helmy, "The IMPORTANT Framework for Analyzing the Impact of Mobility on Performance of Routing for Ad Hoc Networks", AdHoc Networks Journal - Elsevier Science, Vol. 1, Issue 4, pp. 383-403, November 2003. [ Technical Report (.pdf) version] [Full-text with links] [Abstract.]
      
      Link to the IMPORTANT mobility tool website, including mobility traces used for the IMPORTANT paper and the PATHS paper (including Random Waypoint, Group Mobility, Freeway and Manhattan mobility models). The code to be released soon.
      
      
    • F. Bai, N. Sadagopan, A. Helmy, " IMPORTANT: A framework to systematically analyze the Impact of Mobility on Performance of RouTing protocols for Adhoc NeTworks", IEEE INFOCOM (The 22nd Annual Joint Conference of the IEEE Computer and Communications Societies), pp. 825-835, March/April 2003, San Francisco. (Acceptance rate: 20%) [INFOCOM Slides (.ppt) April 2nd, 2003.]
    
    
  • The PATHS mobility analysis:
    • F. Bai, N. Sadagopan, B. Krishnamachary, A. Helmy, "Modeling Path Duration Distributions in MANETs and their Impact on Routing Performance", April 2003 (Submitted for Journal Review). [Journal version of the PATHS paper]
    • N. Sadagopan, F. Bai, B. Krishnamachari, A. Helmy, " PATHS: analysis of PATH duration Statistics and their impact on reactive MANET routing protocols", ACM MobiHoc (The Fourth ACM International Symposium on Mobile Ad Hoc Networking and Computing), June 2003. (Acceptance rate: 15%) [Earlier version as a Technical Report.] (MobiHoc Presentation Slides (.ppt))
    
    
  • Mobility Prediction for Geographic Routing:
    • D. Son, A. Helmy, B. Krishnamachari, "The Effect of Mobility-induced Location Errors on Geographic Routing in Ad Hoc Networks: Analysis and Improvement using Mobility Prediction", IEEE Wireless Communications and Networking Conference (WCNC), March 2004.
    • D. Son, J. Park, A. Helmy, "Mobility-Induced Location Errors and its Effect on Geographic Routing in Ad Hoc Networks: Analysis and Improvement using Mobility Prediction", ACM MOBICOM Conference, San Diego, CA, September 2003. (Refereed Poster) [Extended abstract] [Poster (.pdf)]
    
    
  • Grid/GLS analysis, other mobility models:
    • C. Shete, S. Sawhney, S. Herwadka, V. Mehandru, A. Helmy, "Analysis of the Effects of Mobility and Node Density on the Grid Location Service in Ad Hoc Networks", June 03. (Submitted)
    • K. Dantu, S. Kapadia, R. Sinha, A. Helmy, "Modeling of Mobility-Induced Losses in MANETs (MILMAN)", ACM SIGCOMM Conference, August 2002, Pittsburgh. (Refereed poster) (Extended abstract in ACM SIGCOMM Computer Communications Review (CCR), July 2002). [Poster (.PDF), website]
    • Y. Lu, H. Lin, Y. Gu, A. Helmy, "Towards Mobility-Rich Performance Analysis of Routing Protocols in Ad Hoc Networks: Using Contraction, Expansion and Hybrid Models", June 03. (Submitted)


• Resource Discovery and Small Transfers:
  
  
  • Mobility-Assisted MARQ Architecture:
    • A. Helmy, " Mobility-Assisted Resolution of Queries in Large-Scale Mobile Sensor Networks (MARQ)", Computer Networks Journal - Elsevier Science (Special Issue on Wireless Sensor Networks), Vol. 43, Issue 4, pp. 437-458, November 2003. [With Colors(.pdf)] [Full-text with links] [Abstract.]
    • A. Helmy, "Small Large-Scale Wireless Networks: Mobility-Assisted Resource Discovery", featured in Technology Research News (TRN) Journal, Issue 86, August 21/28, 2002. (Also featured in ACM TechNews, Volume 4, Issue 391, August 26, 2002.)
    • A. Helmy, " Architectural Framework for Large-Scale Multicast in Mobile Ad Hoc Networks", IEEE International Conference on Communications (ICC 2002), Vol. 4, pp. 2036-2042, April 2002, New York. (Longer version.) [Slides (.ppt, .PDF)]
  
  
  • Proactive contact selection (CARD):
    • A. Helmy, S. Garg, P. Pamu, N. Nahata, "CARD: A Contact-based Architecture for Resource Discovery in Ad Hoc Networks", ACM Baltzer Mobile Networks and Applications (MONET) Journal, Kluwer publications, Special issue on Algorithmic Solutions for Wireless, Mobile, Ad Hoc and Sensor Networks. To appear (1st Quarter 2004).
    • A. Helmy, S. Garg, P. Pamu, N. Nahata, "Contact Based Architecture for Resource Discovery (CARD) in Large Scale MANets", Third IEEE/ACM International Workshop on Wireless, Mobile and Ad Hoc Networks (WMAN), proceedings of International IEEE/ACM Parallel and Distributed Processing Symposium IPDPS 2003, pp. 219-227, April 2003, Nice, France. (Abstract .PDF) [Presentation slides (in power point)]
    • N. Nahata, P. Pamu, S. Garg, A. Helmy, "Efficient Resource Discovery for Large Scale Ad hoc Networks using Contacts", ACM SIGCOMM Conference, August 2002, Pittsburgh. (Refereed poster) (Extended abstract in ACM SIGCOMM Computer Communications Review (CCR), July 2002). [Abstract (.PDF), Poster, web site.]
  
  
  • Reactive contact selection (TRANSFER, PARSe):
    • A. Helmy, "Efficient Resource Discovery in Wireless AdHoc Networks: Contacts Do Help", Accepted Book Chapter in the upcoming book on "Resource Management in Wireless Networking" by Kluwer Academic Publishers, To Appear May 2004. (more info about the book)
    • A. Helmy, "TRANSFER: Transactions Routing for Ad-hoc NetworkS with eFficient EneRgy", IEEE GLOBECOM, San Francisco, December 2003. (.pdf) ((Slides in power (.ppt) with animations [5.5MB], Slides in PDF [750KB]).
    • A. Helmy, "CAPTURE: location-free Contact-Assisted Power-efficienT qUery REsolution for Sensor Networks", ACM Mobile Computer and Communications Review (MC2R), Special issue on Wireless PAN and Sensor Networks, Volume 8, Issue 1, January 2004. (Article In Press)
    • A. Helmy, "Contact-extended Zone-based Routing for Transactions in Ad Hoc Networks", July 2003 (Accepted to IEEE Transactions on Vehicular Technology with revision).
    • A. Helmy, "PARSe: Power-efficient Architecture for Resource Discovery and Small-transfers in Large Scale Ad Hoc Networks", USC-CS-TR-02-780, Dec. 02 [Longer version].
  
  
  • Multi-variable Query Resolution (ACQUIRE):
    • N. Sadagopan, B. Krishnamachari, A. Helmy, "Active Query Forwarding in Sensor Networks (ACQUIRE)", AdHoc Networks Journal - Elsevier Science, To appear 4th Quarter 03/1st Quarter 04 (In Press). [Single column version.]
    • N. Sadagopan, B. Krishnamachari, A. Helmy, "The ACQUIRE Mechanism for Efficient Querying in Sensor Networks", First IEEE International Workshop on Sensor Network Protocols and Applications (SNPA), in conjunction with IEEE ICC 2003, pp. 149-155, May 2003, Anchorage, AK, USA.
    • N. Sadagopan, B. Krishnamachari, A. Helmy, "The Acquire Mechanism for Efficient Querying in Sensor Networks", poster presented at the Center for Embedded Networked Sending (CENS) annual research review, UCLA, Oct 03. [Abstract [Poster].
  
  
  • Small Transfers:
    • S. Wang, A. Helmy, "Effects of Small Transfers and Traffic Patterns on Performance and Cache Efficacy of Ad Hoc Routing", ACM MOBICOM Conference, San Diego, CA, September 2003. (Refereed Poster) [Extended Abstract, Poster]
    • S. Wang, A. Helmy, "Effects of Small Transfers and Traffic Patterns on Performance and Cache Efficacy of On-Demand Ad Hoc Routing", IEEE ICNP, Atlanta, GA, Nov. 2003. (Refereed Poster)
    • S. Wang, A. Helmy, "Effects of Small Transfers and Traffic Patterns on Performance and Cache Efficacy of On-Demand Ad Hoc Routing", USC-TR, Dec. 2003. (Submitted for Review)
    
    
  
  
• Geographic-Based Services:
  
  
  • Geographic Rendezvous Regions (RRs):
    • K. Seada, A. Helmy, "Rendezvous Regions: A Scalable Architecture for Service Location and Data-Centric Storage in Large-Scale Wireless Networks", IEEE/ACM IPDPS 4th Int'l Workshop on Algorithms for Wireless, Mobile, Ad Hoc and Sensor Networks (WMAN), Santa Fe, April 2004.
    • K. Seada, A. Helmy, "Rendezvous Regions: A Scalable Architecture for Service Location and Data-Centric Storage in Large-Scale Wireless Networks", ACM MOBICOM Conference, San Diego, CA, September 2003. (Refereed Poster) [Extended Abstract (.pdf)], [Poster (.pdf)]
    • K. Seada, A. Helmy, "Rendezvous Regions: A Scalable Architecture for Service Provisioning in Large-Scale Mobile Ad Hoc Networks", ACM SIGCOMM Conference, Karlsruhe, Germany, August 2003. (Refereed Poster). [Extended abstract to appear in ACM SIGCOMM CCR] [Extended Abstract (.pdf)], [Poster (.pdf)], [Poster (.ppt)], [Website]
    • A. Helmy, " Architectural Framework for Large-Scale Multicast in Mobile Ad Hoc Networks", IEEE International Conference on Communications (ICC 2002), Vol. 4, pp. 2036-2042, April 2002, New York. (Longer version.) [Slides (.ppt, .PDF)]
  
  
  • Geocast:
    • K. Seada, A. Helmy, "Efficient Geocasting with Perfect Delivery in Wireless Networks", IEEE Wireless Communications and Networking Conference (WCNC), March 2004.
  
  
  • Effect of Inaccuracy on Face Routing:
    • K. Seada, A. Helmy, R. Govindan, "On the Effect of Location Inaccuracy on Geographic Face Routing in Wireless Networks", ACM MOBICOM Conference, San Diego, CA, September 2003. (Refereed Poster) [Extended Abstract (.pdf)], [Poster (.pdf)] (one of only 8 posters selected for a future issue of the MC2R publication) [Associated Technical Report, USC-CS-TR-03-707]
    • Karim Seada, Ahmed Helmy, Ramesh Govindan, "On the Effect of Localization Errors on Geographic Face Routing in Sensor Networks", The First ACM Conference on Embedded Networked Sensor Systems (ACM SenSys), November 2003. (Refereed Poster) [Extended abstract to appear in conf. proceedings]. [Extended Abstract (.pdf)], [Poster (.pdf)], [Poster (.ppt)]
    • Karim Seada, Ahmed Helmy, Ramesh Govindan, "On the Effect of Localization Errors on Geographic Face Routing in Sensor Networks", USC CS Technical Report 03-797, June 2003.
  
  
  • Effect of Inconsistency on Geographic Routing:
    • Y. Kim, J. Lee, A. Helmy, "Impact of Location Inconsistencies on Geographic Routing in Wireless Networks", Sixth ACM International Workshop on Modeling, Analysis and Simulation of Wireless and Mobile Systems (MSWIM), in conjunction with ACM MOBICOM, Sept 2003. (Short paper) (Acceptance rate: less than 15%) [(.pdf)][Extended version (.pdf)]
    • Y. Kim, J. Lee, A. Helmy, "Impact of Location Inconsistencies on Geographic Routing in Wireless Networks", ACM Mobile Computer and Communications Review (MC2R), Special issue on Wireless PAN and Sensor Networks, Volume 8, Issue 1, January 2004. (Article In Press)
    
    
  • Geographic Routing with Black-listing over Lossy Links:
    • K. Seada, M. Zuniga, A. Helmy, B. Krishnamachari, "Energy-Efficient Forwarding Strategies for Geographic Routing in Loss Wireless Sensor Networks", Nov. 2003. (Submitted for Review)
    
    
  • Mobility Prediction for Geographic Routing:
    • D. Son, A. Helmy, B. Krishnamachari, "The Effect of Mobility-induced Location Errors on Geographic Routing in Ad Hoc Networks: Analysis and Improvement using Mobility Prediction", IEEE Wireless Communications and Networking Conference (WCNC), March 2004.
    • D. Son, J. Park, A. Helmy, "Mobility-Induced Location Errors and its Effect on Geographic Routing in Ad Hoc Networks: Analysis and Improvement using Mobility Prediction", ACM MOBICOM Conference, San Diego, CA, September 2003. (Refereed Poster) [Extended abstract] [Poster (.pdf)]
    
    
  • Grid Location Service (GLS) analysis:
    • C. Shete, S. Sawhney, S. Herwadka, V. Mehandru, A. Helmy, "Analysis of the Effects of Mobility and Node Density on the Grid Location Service in Ad Hoc Networks", June 03. (Submitted)
  
  
• Gradient-based Routing:
  
  
  • The RUGGED Protocol:
    • J. Faruque, A. Helmy, "RUGGED: RoUting on finGerprint Gradients in sEnsor Networks", USC-CS-TR-03-806, November 2003. (Submitted for review).
    • J. Faruque, A. Helmy, "Gradient-Based Routing in Sensor Networks", ACM MOBICOM Conference, San Diego, CA, September 2003. (Refereed Poster) [Extended Abstract (.ps)][Poster (.pdf)] (one of only 8 posters selected for a future issue of the MC2R publication) [Associated Technical Report, USC-CS-TR-03-806]
    • J. Faruque, A. Helmy, "Routing on Information Gradients in Sensor Networks", IEEE ICNP, Atlanta, GA, Nov. 2003. (Refereed Poster)


• Small Worlds and Short Cuts in Wireless Networks:
  
  
  • Small World Analysis:
    • A. Helmy, "Small Worlds in Wireless Networks", IEEE Communications Letters, pp. 490-492, Vol. 7, No. 10, October 2003.
    • A. Helmy, "Small Large-Scale Wireless Networks: Mobility-Assisted Resource Discovery", featured in Technology Research News (TRN) Journal, Issue 86, August 21/28, 2002. (Also featured in ACM TechNews, Volume 4, Issue 391, August 26, 2002.)
  
  
  • Wired Short Cuts in Sensor Networks:
    • R. Chitradurga, A. Helmy, "Analysis of Wired Short Cuts in Wireless Sensor Networks", Dec 03 (Submitted for Review).
  
  
• Others:
  
  
  • Secure Locations and Trust Routing (TRANS):
    • S. Tanachaiwiwat, P. Dave, R. Bhindwale, A. Helmy, "Location-centric Isolation of Misbehavior and Trust Routing in Energy-constrained Sensor Networks", Dec 03. (Submitted for Review).
    • S. Tanachaiwiwat, P. Dave, R. Bhindwale, A. Helmy, "Secure Locations: Routing on Trust and Isolating Compromised Sensors in Location-aware Sensor Networks", The First ACM Conference on Embedded Networked Sensor Systems (ACM SenSys), November 2003. (Refereed Poster) [Extended abstract to appear in conf. proceedings] [Extended Abstract Proceedings of ACM SenSys, pp. 218-219, Nov.03] [Poster ]
    • S. Tanachaiwiwat, P. Dave, R. Bhindwale, A. Helmy, "Insecure Location Avoidance and Routing on Trust in Location-aware Sensor Networks", IEEE ICNP, Atlanta, GA, Nov. 2003. (Refereed Poster)
  
  
  • MAC testing
    • S. Begum, S. Gupta, A. Helmy, "An Error Oriented Test Generation (EOTG) Framework for Wireless Adhoc MAC Protocols", IEEE ICNP (11th IEEE International Conference on Network Protocols), Atlanta, GA, November 2003. (Refereed Poster) [Extended version submitted for review].
  
  
  • Project Overview:
    • A. Helmy, "Resource Discovery, Query Resolution & Rendezvous in Large-Scale Wireless Networks: Architectural Design & Analysis", project poster presented at the ECS NSF Workshop on sensor networks and systems, CENS, UCLA, Sept 8, 2003. [Poster (.ppt)], [ Short abstract (html), (.pdf)]
    • Project Proposal (NSF CAREER Award): A. Helmy, "Adaptive Architecture for Multicast Service Support in Large-Scale Mobile Ad Hoc Networks: Design and Evaluation Framework", USC-TR, July 2001.
    • Project Proposal (Intel Research, COMM technical committee): A. Helmy, "Efficient Provisioning for Services in Large-scale Wireless-Wired Networks", USC-TR, September 2002.
  
  

Micro Mobility and Efficient Handoff for IP Mobility

• 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, To Appear 1st Quarter 2004.
• A. Helmy, M. Jaseemuddin, G. Bhaskara, "Efficient Micro-Mobility using Intra-domain Multicast-based Mechanisms (M&M)", ACM SIGCOMM Computer Communications Review (CCR), Volume 32, Number 5, pages 61-72, November 2002. [Published version.] [The CCR November 02 issue.]
• A. Helmy, "State Analysis and Aggregation Study for Multicast-based Micro Mobility", IEEE International Conference on Communications (ICC 2002), Vol. 5, pp. 3301-3306, May 2002, New York. (Longer version.) [Presentation Slides (.ppt)].
• A. Helmy, "A Multicast-based Protocol for IP Mobility Support", ACM SIGCOMM Second International Workshop on Networked Group Communication (NGC 2000), Palo Alto, November 2000. (Longer version) [Presentation Slides (.ppt)].
• G. Bhaskara, A. Helmy, S. Gupta, "Micro Mobility Protocol Design and Evaluation: A Parameterized Building Block Approach", IEEE Vehicular Technology Conference (VTC), October 2003.
• A. Helmy, "Multicast-based Architecture for IP Mobility: Simulation Analysis and Comparison with Basic Mobile IP", featured in Technology Research News (TRN) Journal, issue 1, June 21, 2000. [ ACM-LANL-NCSTRL-cs.NI/0006022].

[Here is a library of topologies I have used for the simulations of M&M (NGC and TRN), in a format compatible with the network simulator (NS-2)].
• A. Helmy, M. Jaseemuddin, "Efficient Micro-Mobility using Intra-domain Multicast-based Mechanisms (M&M)", USC-CS-TR-01-747, Aug 2001.

Systematic Testing (STRESS)

• G. Bhaskara, A. Helmy, S. Gupta, "Micro Mobility Protocol Design and Evaluation: A Parameterized Building Block Approach", IEEE Vehicular Technology Conference (VTC), October 2003.
• S. Begum, S. Gupta, A. Helmy, "An Error Oriented Test Generation (EOTG) Framework for Wireless Adhoc MAC Protocols", IEEE ICNP (11th IEEE International Conference on Network Protocols), Atlanta, GA, November 2003. (Refereed Poster)
• K. Seada, A. Helmy, S. Gupta, "A Framework for Systematic Evaluation of Multicast Congestion Control Protocols", USC Tech Report 03-801, October 2003. (IEEE Journal on Selected Areas in Communications - Accepted)
• K. Seada, A. Helmy, " Fairness Evaluation Experiments for Multicast Congestion Control Protocols", IEEE GLOBECOM, Vol. 3, pp. 2614-2618, Taipei, Taiwan, November 2002. [ Extended version.]
• K. Seada, S. Gupta, A. Helmy, " Systematic Evaluation of Multicast Congestion Control Protocols", SCS International Symposium on Performance Evaluation of Computer and Telecommunication Systems (SPECTS), San Diego, July 02. [ Extended Version.] [Presentation slides (.PDF)]
• A. Helmy, S. Gupta, D. Estrin, "The STRESS Method for Performance Evaluation of End-to-end Multicast Protocols", IEEE/ACM Transactions on Networking (ToN). To appear April 2004. [updated July '02, 'The STRESS Method for Boundary-point Performance Analysis of End-to-end Multicast Timer-Suppression Mechanisms']. [ACM-LANL-NCSTRL]
• A. Helmy, D. Estrin, S. Gupta, "STRESS: A Methodology for Systematic Testing of Multicast Routing Protocols". (In submission for Review).
• A. Helmy, D. Estrin, S. Gupta, "Systematic Testing of Multicast Routing Protocols: Analysis of Forward and Backward Search Techniques", (Extended version at: http://xxx.lanl.gov/abs/cs.NI/0007005).
• A. Helmy, S. Gupta, D. Estrin, A. Cerpa, Y. Yu, "Systematic Performance Evaluation of Multipoint Protocols", Proceedings of FORTE/PSTV, IFIP, Kluwer Academic Publication, Pisa, Italy, October 2000. (Submitted version ps. Extended version pdf, also at: http://xxx.lanl.gov/abs/cs.NI/0006029).
• S. Begum, M. Sharma, A. Helmy, S. Gupta, "Systematic Testing of Protocol Robustness: Case Studies on Mobile IP and MARS", Proceedings of the 25^th annual IEEE conference on Local Computer Networks (LCN), pp. 369-380, Florida, November 2000.
Abstract (Long version).
• 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
• Ph.D. Dissertation:
  A. Helmy, "Systematic Test Synthesis for Multipoint Protocol Design", Ph.D. Dissertation, Advisors: Prof. Deborah Estrin (Chair), Prof. Sandeep Gupta, Prof. Ramesh Govindan, USC-CS-TR-99-716, Computer Science Department, University of Southern California, August 1999. [abstract] [Presentation slides (in power point) are available here.]
• Ph.D. Dissertation Proposal (The basis for the STRESS project):
  A. Helmy, "Systematic Testing of Multicast Protocol Robustness", Ph.D. Dissertation Proposal, Committee: Prof. Deborah Estrin (Chair), Prof. Sandeep Gupta, Prof. Ramesh Govindan, Prof. Maja Mataric, Prof. Cengiz Alaettinoglu, USC-CS-TR-98-663, Computer Science Department, University of Southern California, December 1997.
• A. Helmy, D. Estrin, S. Gupta, "STRESS Testing using Reduced Reachability Analysis: A Case Study for a Multicast Routing Protocol", USC-CS-TR-98-690, December 1998.

Active Queue Marking and Fairness

• A. Das, D. Dutta, A. Helmy, "A Low-state Packet Marking Framework for Approximate Fair Bandwidth Allocation", IEEE ICNP (11th IEEE International Conference on Network Protocols), Atlanta, GA, November 2003. (Refereed Poster)
• A. Das, D. Dutta, A. Helmy, "Fair Stateless Aggregate Marking using Active Queue Management Techniques", IEEE/IFIP International Conference on Management of Multimedia Networks and Services (MMNS), Santa Barbara, CA, October 2002. (Best Paper Award).
• A. Das, D. Dutta, A. Helmy, "A Lightweight Mechanism to Control Misbehaving Flows using AQM-based Aggregate Marking", USC-CS-TR-02-763, July 2002. (Submitted for Review)

Multicast Routing (PIM)

• 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, March 1999. Abstract [Extended]
• 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
• 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 of the Internet Engineering Task Force (IETF), Inter-Domain Multicast Routing (IDMR), June 1998.
• 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", RFC 2117 of the IETF/IDMR, June 1997.
• 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.
• 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.
• A. Helmy, "Protocol Independent Multicast-Sparse Mode (PIM-SM): Implementation Document", Internet-Draft (I-D) of the IDMR/MBone Deployment (Mboned) working groups of IETF, Proceedings of 37th IETF (idmr) meeting, San Jose, California, December 1996.
• S. Deering, W. Fenner, D. Estrin, A. Helmy, D. Farinacci, L. Wei, M. Handley, V. Jacobson, D. Thaler, "Interoperability Mechanisms for PIM and DVMRP", Internet-Draft (I-D) of the IETF/IDMR, December 1995.
• A. Helmy, D. Thaler, D. Estrin, L. Wei, "Protocol Independent Multicast-Sparse Mode (PIM-SM): Deployment Guidelines", Internet-Draft (I-D) of the IETF/Mboned, Proceedings of the 37th IETF meeting, San Jose, California, December 1996.
• A. Helmy, D. Thaler, D. Estrin, "PIM Multicast Border Router (PMBR) specification for connecting PIM-SM domains to a DVMRP Backbone", Internet-Draft (I-D) of the IETF/IDMR, September 1996.
• S. Deering, W. Fenner, D. Estrin, A. Helmy, D. Farinacci, L. Wei, M. Handley, V. Jacobson, D. Thaler, "Hierarchical PIM for Inter-Domain Multicast Routing", Internet-Draft (I-D) of the IETF/IDMR, December 1995.

Network Simulation

• 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
• 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
• S. Bajaj, L. Breslau, D. Estrin, K. Fall, S. Floyd, P. Haldar, M. Handley, A. Helmy, J. Heidemann, P. Huang, S. Kumar, S. McCanne, R. Rejaie, P. Sharma, S. Shenker, K. Varadhan, H. Yu, Y. Xu, D. Zappala, " Virtual InterNetwork Testbed (VINT): Status and Research Agenda", USC-CS-TR-98-678, June 1998.