Alex X. Liu Associate Professor Department of Computer Science and Engineering 428 S. Shaw Lane Room# 3115, Engineering Building Michigan State University East Lansing, MI 48824-1266

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Alex X. Liu received his Ph.D. degree in Computer Science from The University of Texas at Austin in 2006. He received the IEEE & IFIP William C. Carter Award in 2004, the National Science Foundation CAREER Award in 2009, and the Michigan State University Withrow Distinguished Scholar Award in 2011. His special research interests are in networking, security, and privacy. His general research interests include computer systems, distributed computing, and dependable systems.

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Books

• Firewall Design and Analysis
  Alex X. Liu
  World Scientific Publishing Company. ISBN-10: 9814261653. ISBN-13: 9789814261654. December 2010.

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• Hardware Based Packet Classification for High Speed Internet Routers
  Chad R. Meiners, Alex X. Liu, and Eric Torng
  Springer. ISBN-10: 1441966994. ISBN-13: 9781441966995. June 2010.

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Selected Conference Publications

• Probabilistic Optimal Tree Hopping for RFID Identification
  Muhammad Shahzad and Alex X. Liu.
  in Proceedings of the ACM International Conference on Measurement and Modeling of Computer Systems (SIGMETRICS), Pittsburgh, PA, June 2013.
  Acceptance rate: 27/196 =13.8%
  Average review score ranks 3rd among all submissions.

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• A First Look at Cellular Network Performance during Crowded Events
  M. Zubair Shafiq, Lusheng Ji, Alex X. Liu, Jeffrey Pang, Shobha Venkataraman, and Jia Wang.
  in Proceedings of the ACM International Conference on Measurement and Modeling of Computer Systems (SIGMETRICS), Pittsburgh, PA, June 2013.
  Acceptance rate: 27/196 =13.8%

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• A Difference Resolution Approach to Compressing Access Control Lists
  James Daly, Alex X. Liu, and Eric Torng.
  in Proceedings of the 32th Annual IEEE Conference on Computer Communications (INFOCOM), Turin, Italy, April 2013.
  Acceptance rate: 280/1613 =17.4%

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• A Digital Watermarking Approach to Secure and Precise Range Query Processing in Sensor Networks
  Yeqing Yi, Rui Li, Fei Chen, Alex X. Liu, Yaping Lin
  in Proceedings of the 32th Annual IEEE Conference on Computer Communications (INFOCOM), Turin, Italy, April 2013.
  Acceptance rate: 280/1613 =17.4%

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• A Multi-Partitioning Approach to Building Fast and Accurate Counting Bloom Filters
  Kun Huang, Jie Zhang, Dafang Zhang, Gaogang Xie, Kave Salamatian, Alex X. Liu, Wei Li
  in Proceedings of the 27th IEEE International Parallel and Distributed Processing Symposium (IPDPS), Boston, Massachusetts, April 2013.
  Acceptance rate: 106/494 =21.4%

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• A Semantics Aware Approach to Automated Reverse Engineering Unknown Protocols
  Yipeng Wang, Xiaochun Yun, M. Zubair Shafiq, Liyan Wang, Alex X. Liu, Zhibin Zhang, Danfeng(Daphne) Yao, Yongzheng Zhang, and Li Guo.
  in Proceedings of the 20th IEEE International Conference on Network Protocols (ICNP), Austin, Texas, October 2012.
  Acceptance rate: 30/131 = 22.9%
Best Paper Award

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• First Step Toward Cloud-Based Firewalling
  Amir R. Khakpour and Alex X. Liu.
  in Proceedings of the 31st IEEE International Symposium on Reliable Distributed Systems (SRDS), Irvine, California, October 2012.
  Acceptance rate: 28/140= 20%
Best Paper (Runner Up) Award

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• Every Bit Counts - Fast and Scalable RFID Estimation [PDF]
  Muhammad Shahzad and Alex X. Liu
  in Proceedings of the 18th ACM Annual International Conference on Mobile Computing and Networking (MobiCom), Istanbul, Turkey, August 2012.
  Acceptance rate: 32/212 = 15.1%

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• A First Look at Cellular Machine-to-Machine Traffic - Large Scale Measurement and Characterization [PDF]
  M. Zubair Shafiq, Lusheng Ji, Alex X. Liu, Jeffrey Pang, and Jia Wang
  in Proceedings of the ACM International Conference on Measurement and Modeling of Computer Systems (SIGMETRICS), pages 65-76, London, United Kingdom, June 2012.
  Acceptance rate: 31/203 =15.3%

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• A Large Scale Exploratory Analysis of Software Vulnerability Life Cycles [PDF]
  Muhammad Shahzad, M. Zubair Shafiq, and Alex X. Liu
  in Proceedings of the 34th International Conference on Software Engineering (ICSE), Zurich, Switzerland, June 2012.
  Acceptance rate: 87/408 =21.3%

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• A Prefiltering Approach to Regular Expression Matching for Network Security Systems [PDF]
  Tingwen Liu, Yong Sun, Alex X. Liu, Li Guo, and Binxing Fang
  in Proceedings of the 10th International Conference on Applied Cryptography and Network Security (ACNS), pages 363-380, Singapore, June 2012.
  Acceptance rate: 33/192=17.2%.

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• A Task-Based Model for the Lifespan of Peer-to-Peer Swarms [PDF]
  Yong Zhao, Zhibin Zhang, Ting He, Alex X. Liu, Li Guo, and Binxing Fang
  in Proceedings of the 11th IFIP International Conferences on Networking (Networking), pages 71-83, Prague, Czech Republic, May 2012.
  Acceptance rate: 64/225 = 28.4%.

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• FlowSifter: A Counting Automata Approach to Layer 7 Field Extraction for Deep Flow Inspection [PDF]
  Chad Meiners, Eric Norige, Alex X. Liu, and Eric Torng.
  in Proceedings of the 31th Annual IEEE Conference on Computer Communications (INFOCOM), pages 1746-1754, Orlando, Florida, March 2012.
  Acceptance rate: 278/1547 =17.9%

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• Characterizing Geospatial Dynamics of Application Usage in a 3G Cellular Data Network [PDF]
  M. Zubair Shafiq, Lusheng Ji, Alex X. Liu, Jeffrey Pang, and Jia Wang.
  in Proceedings of the 31th Annual IEEE Conference on Computer Communications (INFOCOM), pages 1341-1349, Orlando, Florida, March 2012.
  Acceptance rate: 278/1547 =17.9%

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• Firewall Fingerprinting [PDF]
  Amir R. Khakpour, Joshua W. Hulst, Zihui Ge, Alex X. Liu, Dan Pei, and Jia Wang.
  in Proceedings of the 31th Annual IEEE Conference on Computer Communications (INFOCOM), pages 1728-1736, Orlando, Florida, March 2012.
  Acceptance rate: 278/1547 =17.9%

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• Bypassing Space Explosion in Regular Expression Matching for Network Intrusion Detection and Prevention Systems [PDF]
  Jignesh Patel, Alex Liu, and Eric Torng
  in Proceedings of the 19th Annual Network & Distributed System Security Symposium (NDSS), San Diego, California, February 2012.
  Acceptance rate: 46/258 = 17.8%

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• Privacy-Preserving Cross-Domain Network Reachability Quantification [PDF]
  Fei Chen, Bezawada Bruhadeshwar, and Alex X. Liu
  in Proceedings of the 19th IEEE International Conference on Network Protocols (ICNP), pages 155-164, Vancouver, Canada, October 2011.
  Acceptance rate: 31/189 = 16.4%

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• SPliT: Optimizing Space, Power, and Throughput for TCAM-Based Classification [PDF]
  Chad R. Meiners, Alex X. Liu, Eric Torng, and Jignesh Patel
  in Proceedings of the 7th ACM/IEEE Symposium on Architectures for Networking and Communications Systems (ANCS), pages 200-210, Brooklyn, New York, October 2011.
  Acceptance rate: 20/62 = 32.3%

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• NcRNA Homology Search Using Hamming Distance Seeds [PDF]
  Osama Aljawad, Yanni Sun, Alex Liu, and Jikai Lei
  in Proceedings of the ACM Conference on Bioinformatics, Computational Biology and Biomedicine (BCB), Chicago, Illinois, August 2011.
  Acceptance rate: 29/153 = 18.9%

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• Characterizing and Modeling Internet Traffic Dynamics of Cellular Devices [PDF]
  M. Zubair Shafiq, Lusheng Ji, Alex X. Liu, and Jia Wang
  in Proceedings of the International Conference on Measurement and Modeling of Computer Systems (SIGMETRICS), pages 305-316, San Jose, California, June 2011.
  Acceptance rate: 26/177 = 14.6%

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• A Random Walk Approach to Modeling the Dynamics of the Blogosphere [PDF]
  M. Zubair Shafiq and Alex X. Liu
  in Proceedings of the International Conferences on Networking (Networking), pages 294-306, Valencia, Spain, May 2011.
  Acceptance rate: 64/294 = 21.7%.

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• A Cross-Domain Privacy-Preserving Protocol for Cooperative Firewall Optimization [PDF]
  Fei Chen, Bezawada Bruhadeshwar, and Alex X. Liu
  in Proceedings of the 30th Annual IEEE Conference on Computer Communications (INFOCOM), pages 2903-2911, Shanghai, China, April 2011.
  Acceptance rate: 291/1283 = 15.9%.

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• A Distributed and Privacy-Preserving Algorithm for Identifying Information Hubs in Social Networks [PDF]
  Muhammad U. Ilyas, M. Zubair Shafiq, Alex X. Liu and Hayder Radha
  in Proceedings of the 30th Annual IEEE Conference on Computer Communications (INFOCOM) Mini-Conference, pages 561-565, Shanghai, China, April 2011.
  Acceptance rate: (291+136)/1283 = 23.4%.

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• Collaborative Firewalling in Wireless Networks [PDF]
  Mahmoud Taghizadeh, Amir R. Khakpour, Alex X. Liu, and Subir Biswas
  in Proceedings of the 30th Annual IEEE Conference on Computer Communications (INFOCOM) Mini-Conference, pages 46-50, Shanghai, China, April 2011.
  Acceptance rate: (291+136)/1283 = 23.4%.

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• Offset Addressing Approach to Memory-Efficient IP Address Lookup [PDF]
  Kun Huang, Gaogang Xie, Yanbiao Li, and Alex X. Liu
  in Proceedings of the 30th Annual IEEE Conference on Computer Communications (INFOCOM) Mini-Conference, pages 306-310, Shanghai, China, April 2011.
  Acceptance rate: (291+136)/1283 = 23.4%.

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• Large Scale Hamming Distance Query Processing [PDF]
  Alex X. Liu, Ke Shen, and Eric Torng
  in Proceedings of the 27th IEEE International Conference on Data Engineering, (ICDE), pages 553-564, Hannover, Germany, April, 2011.
  Acceptance rate: 98/494 = 19.8%.

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• First Step Towards Automatic Correction of Firewall Policy Faults [PDF]
  Fei Chen, Alex X. Liu, JeeHyun Hwang, and Tao Xie
  in Proceedings of the 24th USENIX Large Installation System Administration Conference (USENIX LISA), pages 75-90, San Jose, California, November 2010.
  Best Student Paper Award

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• Transforming Range Queries to Equivalent Box Queries to Optimize Page Access [PDF]
  Sakti Pramanik, Alok Watve, Chad R. Meiners, and Alex X. Liu
  in Proceedings of the 36th International Conference on Very Large Data Bases (VLDB), pages 409-416, Singapore, September 2010.
  Acceptance rate: 48/261 = 18.4%.

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• Fast Regular Expression Matching using Small TCAMs for Network Intrusion Detection and Prevention Systems [PDF]
  Chad R. Meiners, Jignesh Patel, Eric Norige, Eric Torng, and Alex X. Liu
  in Proceedings of the 19th USENIX Security Symposium (USENIX Security), pages 111-126, Washington, DC, August 2010.
  Acceptance rate: 30/202 = 14.8%.

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• Quantifying and Querying Network Reachability [PDF]
  Amir R. Khakpour and Alex X. Liu
  in Proceedings of the 29th International Conference on Distributed Computing Systems (ICDCS), pages 817-826, Genoa, Italy, June 2010.
  Acceptance rate: 84/585 = 14%.

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• SafeQ: Secure and Efficient Query Processing in Sensor Networks [PDF]
  Fei Chen and Alex X. Liu
  in Proceedings of the 29th Annual IEEE Conference on Computer Communications (INFOCOM), pages 2642-2650, San Diego, California, March 2010.
  Acceptance rate: 276/1575 =17.5%
  

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• CENDA-Camouflage Event Based Malicious Node Detection Architecture [PDF]
  Kanthakumar Pongaliur, Li Xiao, Alex X. Liu.
  in Proceedings of the IEEE International Symposium on Trust, Security and Privacy for Pervasive Applications (TSP), pages 848-855, Macau, China, October, 2009.
  Acceptance rate: 27/85 = 31.7%
  Best Paper Award
  

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• Bit Weaving: A Non-prefix Approach to Compressing Packet Classifiers in TCAMs [PDF]
  Chad R. Meiners, Alex X. Liu, and Eric Torng
  in Proceedings of the 17th IEEE International Conference on Network Protocols (ICNP), pages 93-102, Princeton, New Jersey, October 2009.
  Acceptance rate: 36/197=18.3%
  

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• Fault Localization for Firewall Policies [PDF]
  Jeehyun Hwang, Tao Xie, Fei Chen, and Alex X. Liu
  in Proceedings of the 28th IEEE International Symposium on Reliable Distributed Systems (SRDS), pages 100-106, Niagara Falls, New York, September 2009.
  Acceptance rate: 30/104 = 28.8%

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• Topological Transformation Approaches to Optimizing TCAM-Based Packet Processing Systems [PDF]
  Chad R. Meiners, Alex X. Liu, and Eric Torng
  in Proceedings of the International Conference on Measurement and Modeling of Computer Systems (SIGMETRICS), pages 73-84, Seattle, Washington, June 2009.
  Acceptance rate: 27/180 = 15%.

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• High-speed Flow Nature Identification [PDF]
  Amir R. Khakpour and Alex X. Liu
  in Proceedings of the 29th International Conference on Distributed Computing Systems (ICDCS), pages 510-517, Montreal, Quebec, Canada, June 2009.
  Acceptance rate: 74/455 = 16%.

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• Collaborative Enforcement of Firewall Policies in Virtual Private Networks [PDF][BibTex]
  Alex X. Liu and Fei Chen
  in Proceedings of the Annual ACM SIGACT-SIGOPS Symposium on Principles of Distributed Computing (PODC), pages 95-104, Toronto, Canada, August 2008.
  Average review score = (4 + 4 + 4)/3 = 4 out of 5.
  Acceptance rate: 40/132 = 30%
  

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• XEngine: A Fast and Scalable XACML Policy Evaluation Engine [PDF][BibTex]
  Alex X. Liu, Fei Chen, JeeHyun Hwang, and Tao Xie
  in Proceedings of the International Conference on Measurement and Modeling of Computer Systems (SIGMETRICS), Pages 265-276, Annapolis, Maryland, June 2008.
  Acceptance rate: 36/201 = 18%. Average review score = 8.7 out of 10. Ranked 2nd among all submissions.
  Sample quotes from diligent reviewers
  Full version is available here: [PDF]
  

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• All-Match Based Complete Redundancy Removal for Packet Classifiers in TCAMs [PDF][BibTex]
  Alex X. Liu, Chad R. Meiners, and Yun Zhou
  in Proceedings of the 27th Annual IEEE Conference on Computer Communications (INFOCOM), pages 574-582, Phoenix, Arizona, April 2008.
  Average review score = (4 + 4 + 4)/3 = 4.
  Acceptance rate: 236/1160 =20.3%
  

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• Firewall Compressor: An Algorithm for Minimizing Firewall Policies [PDF][BibTex]
  Alex X. Liu, Eric Torng, and Chad Meiners
  in Proceedings of the 27th Annual IEEE Conference on Computer Communications (INFOCOM), pages 691-699, Phoenix, Arizona, April 2008.
  Acceptance rate: 236/1160 =20.3%
  

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• Symmetric Key Approaches to Securing BGP -- A Little Bit Trust is Enough [PDF][BibTex]
  Bezawada Bruhadeshwar, Sandeep S. Kulkarni, and Alex X. Liu
  in Proceedings of the 12th European Symposium Research Computer Security (ESORICS), pages 82-96, Malaga, Spain, October, 2008.
  Acceptance rate: 37/168 =22%
  

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• Systematic Structural Testing of Firewall Policies [PDF][BibTex]
  Jeehyun Hwang, Tao Xie, Fei Chen, and Alex X. Liu
  in Proceedings of the 27th IEEE International Symposium on Reliable Distributed Systems (SRDS), Napoli, Italy, October, 2008.
  Acceptance rate: 28/112 =25%

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• TCAM Razor: A Systematic Approach Towards Minimizing Packet Classifiers in TCAMs [PDF][BibTex]
  Chad R. Meiners, Alex X. Liu, and Eric Torng
  in Proceedings of the 15th IEEE International Conference on Network Protocols (ICNP), pages 226-275, Beijing, China, October 2007.
  Acceptance rate: 32/220=14.5%
  

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• Change-Impact Analysis of Firewall Policies [PDF][BibTex]
  Alex X. Liu
  in Proceedings of the 12th European Symposium Research Computer Security (ESORICS), pages 155-170, Dresden, Germany, September 2007.
  Acceptance rate: 39/164=23.7%
  

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• A Model of Stateful Firewalls and its Properties [PDF][BibTex]
  Mohamed G. Gouda and Alex X. Liu
  in Proceedings of the IEEE International Conference on Dependable Systems and Networks (DSN), pages 128-137, Yokohama, Japan, June 2005.
  Acceptance rate: 78/319=24.5%
  

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• Diverse Firewall Design [PDF][BibTex]
  Alex X. Liu and Mohamed G. Gouda
  in Proceedings of the IEEE International Conference on Dependable Systems and Networks (DSN), pages 595-604, Florence, Italy, June 2004.
  Acceptance rate: 83/377=22.0%
  William C. Carter Award

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• Firewall Design: Consistency, Completeness and Compactness [PDF][BibTex]
  Mohamed G. Gouda and Alex X. Liu
  in Proceedings ofthe 24th IEEE International Conference on Distributed Computing Systems (ICDCS), pages 320-327, Tokyo, Japan, March 2004.
  Acceptance rate: 72/406=17.7%
  

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Selected Journal Publications:

• Fast Regular Expression Matching Using Small TCAM
  Chad R. Meiners, Jignesh Patel, Eric Norige, Alex X. Liu, and Eric Torng.
  IEEE/ACM Transactions on Networking (ToN), in press, 2013.
  

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• Identifying Leaders and Followers in Online Social Networks
  M. Zubair Shafiq, Muhammad U. Ilyas, Alex X. Liu, and Hayder Radha.
  IEEE Journal on Selected Areas in Communications (JSAC), in press, 2012.
  

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• A Distributed Algorithm for Identifying Information Hubs in Social Networks
  Muhammad U. Ilyas, M. Zubair Shafiq, Alex X. Liu, and Hayder Radha.
  IEEE Journal on Selected Areas in Communications (JSAC), in press, 2012.
  

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• An Information Theoretical Approach to High-Speed Flow Nature Identification
  Amir R. Khakpour and Alex X. Liu.
  IEEE/ACM Transactions on Networking (ToN), in press, 2012.
  

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• Cross-Domain Privacy-Preserving Cooperative Firewall Optimization
  Fei Chen, Bezawada Bruhadeshwar, and Alex X. Liu.
  IEEE/ACM Transactions on Networking (ToN), in press, 2012.
  

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• Quantifying and Verifying Reachability for Access Controlled Networks
  Alex X. Liu and Amir R. Khakpour.
  IEEE/ACM Transactions on Networking (ToN), in press, 2012.
  

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• Privacy and Integrity Preserving Range Queries in Sensor Networks [PDF]
  Fei Chen and Alex X. Liu.
  IEEE/ACM Transactions on Networking (ToN), in press, 2012.
  

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• A Secure Cookie Scheme [PDF]
  Alex X. Liu, Jason M. Kovacs, and Mohamed G. Gouda
  Journal of Computer Networks (COMNET) (Elsevier), Vol. 56, No. 6, pages 1723-1730, January 2012.
  Note: The web security scheme proposed in this paper has been used by Wordpress since version 2.4. Wordpress is a widely used open source content management system. The adoption of our scheme was announced by Ryan Boren, a lead developer of WordPress, in 2007 in his article "Secure Cookies and Passwords". Our paper was also selected as part of the course material in Stanford Computer Science Course CS259 "Security Modeling and Analysis" in 2012.

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• Dynamic Camouflage Event Based Malicious Node Detection Architecture [PDF]
  Kanthakumar Pongaliur, Li Xiao, and Alex X. Liu.
  Journal of Supercomputing (Springer), in press, 2012.
  

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• TCAMChecker: A Software Approach to the Error Detection and Correction of TCAM-based Networking Systems[PDF]
  Kanthakumar Pongaliur, Li Xiao, and Alex X. Liu.
  Journal of Network and Systems Management (JNSM) (Springer), May 2012.
  

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• Bit Weaving: A Non-prefix Approach to Compressing Packet Classifiers in TCAMs [PDF]
  Chad R. Meiners, Alex X. Liu, and Eric Torng.
  IEEE/ACM Transactions on Networking (ToN), Vol. 20, No. 2, pages 488-500, April 2012.
  

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• Systematic Structural Testing of Firewall Policies [PDF]
  Jeehyun Hwang, Tao Xie, Fei Chen, and Alex X. Liu.
  IEEE Transactions on Network and Service Management (TNSM), Vol. 9, No. 1, pages 1-11, March 2012.
  

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• Firewall Policy Change-Impact Analysis [PDF]
  Alex X. Liu
  ACM Transactions on Internet Technology (TOIT), Vol. 11, No. 4, pages 15:1-15:24, March 2012.
  Note: This paper was selected as the course material in Purdue's Computer Science Course CS 590N ``Logical Methods for Information Security''.

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• First Step Towards Automatic Correction of Firewall Policy Faults [PDF]
  Fei Chen, Alex X. Liu, JeeHyun Hwang, and Tao Xie.
  ACM Transactions on Autonomous and Adaptive Systems (TAAS), Vol. 7, No. 2, 2012.
  

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• Towards High Performance Security Policy Evaluation [PDF]
  Zheng Qin, Fei Chen, Qiang Wang, Alex X. Liu, Zhiguang Qin.
  Journal of Supercomputing (Springer), Vol. 59, No. 3, pages 1577-1595, March, 2012.
  

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• Genome-scale NCRNA homology search using a Hamming distance-based filtration strategy [PDF]
  Yanni Sun, Osama Aljawad, Jikai Lei, Alex Liu.
  BMC Bioinformatics, Vol. 13, No. 3, pages 1-13, March, 2012.
  

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• Compressing Network Access Control Lists [PDF]
  Alex X. Liu, Eric Torng, and Chad R. Meiners
  IEEE Transactions on Parallel and Distributed Systems (TPDS), Vol. 22, No. 12, pages 1969 - 1977, December 2011.
  

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• Designing Fast and Scalable XACML Policy Evaluation Engines [PDF]
  Alex X. Liu, Fei Chen, JeeHyun Hwang, and Tao Xie
  IEEE Transactions on Computers (TC), Vol. 60, No. 12, pages 1802 - 1817, December 2011.
  

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• Privacy Preserving Collaborative Enforcement of Firewall Policies in Virtual Private Networks [PDF]
  Alex X. Liu and Fei Chen
  IEEE Transactions on Parallel and Distributed Systems (TPDS), Vol. 22, No. 5, pages 887 - 895, May 2011.
  

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• Symmetric Key Approaches to Securing BGP -- A Little Bit Trust is Enough [PDF]
  Bezawada Bruhadeshwar, Sandeep S. Kulkarni, and Alex X. Liu
  IEEE Transactions on Parallel and Distributed Systems (TPDS), Vol. 22, No. 2, pages 1536-1549, January 2011.
  

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• TCAM Razor: A Systematic Approach Towards Minimizing Packet Classifiers in TCAMs [PDF]
  Alex X. Liu, Chad R. Meiners, and Eric Torng
  IEEE/ACM Transactions on Networking (ToN), Vol. 18, No. 2, pages 490 - 500, April 2010.

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• Complete Redundancy Removal for Packet Classifiers in TCAMs [PDF]
  Alex X. Liu and Mohamed G. Gouda
  IEEE Transactions on Parallel and Distributed Systems (TPDS), Vol. 21, No. 4, pages 424-437, April 2010.
  Note: This paper was selected as the course material in Purdue's Computer Science Course CS 590N ``Logical Methods for Information Security''.

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• Topological Transformation Approaches to TCAM-Based Packet Classification [PDF]
  Chad R. Meiners, Alex X. Liu, and Eric Torng
  IEEE/ACM Transactions on Networking (ToN), Vol. 19, No. 1, pages 237-250, February 2010..
  

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• Firewall Policy Verification and Troubleshooting [PDF]
  Alex X. Liu
  Journal of Computer Networks (COMNET) (Elsevier), Vol. 53, No. 16, pages 2800-2809, November 2009.
  

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• Firewall Policy Queries [PDF] [BibTex]
  Alex X. Liu and Mohamed G. Gouda
  IEEE Transactions on Parallel and Distributed Systems (TPDS), Vol. 20, No. 6, pages 766-777, June 2009.
  

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• PAP: A Privacy and Authentication Protocol for Passive RFID Tags [PDF][BibTex]
  Alex X. Liu and LeRoy Bailey
  Journal of Computer Communications (COMCOM) (Elsevier), Vol. 32, Issues 7-10, Pages 1194-1199, May 2009.

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• Diverse Firewall Design [PDF][BibTex]
  Alex X. Liu and Mohamed G. Gouda
  IEEE Transactions on Parallel and Distributed Systems (TPDS), Vol. 19, No. 8. August 2008 (Conference version appeared in DSN-2004 and won William C. Carter Award)
  

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• SPP: An Anti-phishing Single Password Protocol [PDF][BibTex]
  Mohamed G. Gouda, Alex X. Liu, Lok M. Leung, and Mohamed A. Alam
  Journal of Computer Networks (COMNET) (Elsevier), Vol. 51, No. 13, pages 1389-1286, September, 2007
  

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• Structured Firewall Design [PDF][BibTex]
  Mohamed G. Gouda and Alex X. Liu
  Journal of Computer Networks (COMNET) (Elsevier), Vol. 51, No. 4, pages 1106-1120, March 2007
  

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• Key Bundles and Parcels: Secure Communication in Many Groups [PDF][BibTex]
  Eunjin Jung, Alex X. Liu, and Mohamed G. Gouda
  Journal of Computer Networks (COMNET) (Elsevier), Vol. 50, No. 11, pages 1781-1798, August 2006
  

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Selected Recent Professional Activities

• Journal Editorship:
• Associate Editor, IEEE/ACM Transactions on Networking (ToN)
• Area Editor, Journal of Computer Communications (COMCOM) (Elsevier)
• Conference/Workshop Organization:
• TPC CO-Chair, the 7th workshop on Secure Network Protocols (NPSec 2012)
• Finance chair: SIGMETRICS 2010.
• Publication chair: SIGMETRICS 2009.
• Regional Arrangements Committee Member: CCS 2009.
• TPC Membership:
• SIGMETRICS: 2013.
• ICNP: 2012, 2007.
• INFOCOM: 2010, 2009.
• ICDCS: 2008, 2007.
• WWW: 2007.

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Graduated Ph.D. Students:
I owe all I have achieved to the people that I have worked with, especially my intelligent and diligent students. My students graduated all have excellent publication records and excellent job placement with high salary (starting salary ranging from $110+K to $150+K).
(1) Chad Meiners (2010, employment upon graduation: MIT Licoln Laboratory): 1 SIGMETRICS, 1 USENIX Security, 1 VLDB, 2 ICNP, 3 INFOCOM, 1 ANCS, 3 ToN, 1 TPDS.
(2) Fei Chen (2011, employment upon graduation: VMware): 1 SIGMETRICS, 1 PODC, 1 ICNP, 2 INFOCOM, 1 USENIX LISA Best Student Paper, 2 ToN, 1 TC, 1 TPDS, 1 TAAS, 1 TNSM.
(3) Amir R. Khakpour (2012, employment upon graduation: EdgeCast): 2 ICDCS, 1 INFOCOM, 1 SRDS Best Paper, 1 INFOCOM Mini, 2 ToN.

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