Tian Bu  Member of Technical Staff Wireless Network Elements Research Department Bell Labs, Lucent Technologies 4G-518  101 Crawfords Corner Road Holmdel, New Jersey 07733-3030 (732) 949-8848 (Office) email: tbu AT bell-labs DOT com

Education

I obtained my Ph.D. from the Computer Networks Research Group in the Computer Science Department at the University of Massachusetts at Amherst. 

Research Interests

• Wireless Network
• Network Security
• Network Modeling and Performance Evaluation

Selected Projects

• 3G Wireless Security
  
  In this project, our goal is to identify the vulnerabilities in current 3G wireless networks (both CDMA and UMTS) for better protection against a variety of threat such as wireless specific DoS. We have demonstrated through extensive real world experiments and simulations that the 3G networks not only share all kinds of wireline network vulnerabilities but also have their specific vulnerabilities. This makes the 3G network even more fragile than the traditional wireline network. Moreover, the wireless specific vulnerabilities cannot be protected using any existing defense mechanism. We have proposed and evaluated a set of architecture enhancements, protocols, and algorithms for better protecting 3G network. We are in the process of incorporating some of our defense mechanism in to 3G standard.
  
• VoIP/IMS Security
  
  Although more and more service providers have rolled out their VoIP network, the fundamental challenge of securing the VoIP  is not well addressed. VoIP is vulnerable to attacks targeting both IP network and the traditional phone network. Malicious packets may be injected and sensitive packets snooped in IP networks from a distance. DoS attacks can be launched by botnets of hundreds of thousands of infected machines belonging to innocent individuals. In this project, we are proposing a comprehensive set of measures from hardening boxes, guarding the border, to mitigating denial of service for a more secure VoIP network. 
  
  As more wireless access technologies such as EV-DO become prevalent, efficiently securing VoIP over these links is essential. This is due to the limited resources such as bandwidth, processing power, and energy in a wireless network. In addition, wireless networks are also more vulnerable to new VoIP specific DoS attacks such as SIP floods. Furthermore, security may degrade wireless performance and interfere with wireless performance enhancements such as Robust Header Compression (ROHC). We are proposing  a secure IMS-based VoIP architecture for EV-DO/UMTS that trades off  the performance and security. This includes optimizing the performance of security protocols such as TLS, SRTP and IPsec and minimizing the impact of security on performance enhancements.
  

Selected Publications  

Design and Evaluation of a Fast and Robust Worm Detection Algorithm
Tian Bu,  Aiyou Chen,  Scott Vander Wiel,  Thomas Woo
To appear in Proceedings of INFOCOM 2006

On the TCP-Friendliness of VoIP Traffic
Tian Bu,  Yong Liu,  and Don Towsley
To appear in Proceedings of INFOCOM 2006

 Generalized Proportional Fair Scheduling in Third Generation Wireless Data Networks
Tian Bu,  Li Li, Ramachandran Ramjee
To appear in Proceedings of INFOCOM 2006

Designing Wireless Radio Access Networks for Third Generation Cellular Networks
Tian Bu, Mun Choon Chan and Ram Ramjee
Proceedings of INFOCOM 2005

Connectivity, Performance, and Resiliency of IP-Based CDMA Radio Access Network
Tian Bu, Mun Choon Chan and Ram Ramjee
Proceedings of INFOCOM 2004

Trading Resiliency for Security: Model and Algorithms
Tian Bu, Samphel Norden, and Thomas Woo
Proceedings of ICNP 2004 

Defending against novel DoS attacks in 3G Wireless Networks, 
Tian Bu, Samphel Norden, and Thomas Woo
Accepted at 3rd ACM Workshop on Wireless Security (WiSe), October 2004.

Network Tomography on General Topology
Tian Bu, Nick Duffield, Francesco Lo Presti, and Don Towsley
Proceedings of ACM SIGMETRICS 2002 

On Distinguishing between Internet Power Law Topology Generators
Tian Bu and Don Towsley
Proceedings of INFOCOM 2002 

On Routing Table Growth
Tian Bu, Lixin Gao, and Don Towsley
To appear in Proceedings of Globe Internet 2002 

Fixed Point Approximation for TCP behavior in an AQM Network
Tian Bu and Don Towsley
Proceedings of ACM SIGMETRICS 2001

Tree Layout for Internal Network Characterizations in Multicast Networks
Micah Adler, Tian Bu, Ramesh K. Sitaraman, Don Towsley
Proceedings of Third International Workshop on Networked Group Communication. London, Nov. 2001

The Use of End-to-end Multicast Measurements for Characterizing Internal Network Behavior
A. Adams, T. Bu, T.Friedman, J. Horowitz, D. Towsley, R. Caceres, N. Duffield, F. Lo Presti,S.B. Moon, V. Paxson.
IEEE Communications Magazine May 2000.

Multicast-Based Inference of Network-Internal Characteristics: Accuracy of Packet Loss Estimation
R. Caceres, N.G., Duffield, J. Horowitz, D. Towsley and T. Bu
Proceedings of INFOCOM'99.
* drop me a line if google cannot find you a copy of any of these papers  

Last updated 01/06