Ray Kong Lam

R. C. Lee Centenary Scholar Ph.D. Student
Personal Homepage Curriculum Vitae
Address	Department of Computer Science Siebel Center for Computer Science 201 N Goodwin Ave Urbana, IL 61801-2302 USA
Office	SIEBL 3111
E-mail	konglam2 at uiuc.edu

Biography

Ray Kong Lam is an R. C. Lee Centenary Scholar and a Ph.D. student of Computer Science at the University of Illinois at Urbana-Champaign (UIUC). He obtained his B.Eng. in Internet Engineering and M.Phil. in Computer Science & Engineering from the Chinese University of Hong Kong (CUHK) in 2004 and 2006 respectively. He is now starting his Ph.D. research on wireless networks with his advisor Prof. Jennifer C. Hou, and is investigating topics such as the modeling, topology control, and multi-channel assignment of IEEE 802.11-based wireless mesh networks. He is also working on a project for supporting MAC/PHY parameter tuning in network devices and studying a course on communication network analysis. He is a member of the Illinois Network Design and Experimentation (INDEX) Group.

Publications

Refereed Conference Papers

• R. K. Lam, D.-M. Chiu and J. C. S. Lui,
  "On the access pricing issues of wireless mesh networks,"
  in Proc. IEEE ICDCS'06, Lisboa, Portugal, June 4-7, 2006.
  • Acceptance ratio: 14%
  • Paper | Slides

Theses

• K. Lam,
  "On the access pricing and network scaling issues of wireless mesh networks,"
  M.Phil. thesis, The Chinese Univ. of Hong Kong, Hong Kong, September 2006.
  
  
• K. Lam and S. L. Wong,
  "Distributed denial-of-service (DDoS) attack: from understanding to creation to defending your territory,"
  B.Eng. thesis, The Chinese Univ. of Hong Kong, Hong Kong, May 2004.
  • Paper | Slides

Honors

• The R C Lee Centenary Scholarship, 2006
  
• The Best Teaching Assistant Award, The Chinese University of Hong Kong, 2006
  
• Merit for Excellent Teaching Assistantship, The Chinese University of Hong Kong, 2006
  
• Merit for Excellent Teaching Assistantship, The Chinese University of Hong Kong, 2005
  
• Distinguished Academic Scholarship, The Chinese University of Hong Kong, 2004
  
• Dean's List, three years, The Chinese University of Hong Kong, 2004, 2003, 2002
  
• Yu To Sang Memorial Scholarship, two years, 2004, 2002
  
• Department/Programme Scholarship, two years, The Chinese University of Hong Kong, 2003, 2002
  
• Chiap Hua Cheng's Foundation Scholarship, 2003
  
• Youth Leadership Award, Global Young Leaders Conference, 2000

Research

Research Interests

• Wireless mesh networks
• Network analysis and performance evaluation
• Information theory
• Game theory
• Network economics

Wireless Mesh Networks Project (Current Project)

Wireless mesh network is an emerging network architecture for the next-generation wireless Internet. While the current IEEE 802.11 wireless networks require every wireless client to connect the access point directly in order to access the Internet, wireless mesh networks employ multi-hop routing, i.e. a wireless client may route through numerous wireless relaying nodes to reach the access point. The new architecture is promising on solving the "last mile" problem for broadband access:

• it is more cost effective as Internet service providers need not install a wireline connection to each subscriber;
• it is more reliable as each wireless client has redundant wireless paths to the Internet;
• it can achieve higher throughput compared to existing IEEE 802.11 wireless networks through the use of multiple bandwidth-abundant paths;
• it is more scalable as the network coverage can be extended by installing additional wireless relaying nodes.

In this project, we strive toward the following research thrusts, covering both theoretical and system aspects:

• How to model the channel activities in IEEE 802.11-based wireless mesh networks? Existing works by Bianchi and Kumar et al. give account to the performance of IEEE 802.11 single-cell networks. How can we extend and apply their models in multi-hop wireless mesh networks? In particular, we need to incorporate the effect of PHY/MAC attributes, such as transmission power and carrier sense threshold, which is not an issue in single-cell networks but is of significance in the new architecture. With an analytical model, we are able to develop distributed algorithms to adjust transmission power, carrier sense threshold, etc. to optimize the performance of the network.
• Topology control is another important topic in wireless mesh networks. The key idea of topology control is that, instead of using the maximum transmission power, nodes in the network collaboratively determine the (individual) power they use, so that a neighbor relation is determined, maintaining network connectivity while improving network capacity. Current topology control algorithms often ignore the effect of physical signal interference. In this work, we investigate topology control in wireless mesh networks under appropriate physical models. A recent work by Moscibroda et al. addresses the issue with a focus on bounding the scheduling complexity.
• To further improve the capacity of wireless mesh networks, people propose to exploit wireless channel diversity, i.e. wireless nodes are to be equipped with multiple radios and communicate on multiple channels simultaneously. The problem is then the channel assignment of each node's multiple interfaces. To develop a channel assignment algorithm to optimize the throughput of the network, factors such as the positions of nodes, the number of nodes with multiple radios, the nodes' transmission power, etc. will have to be considered.
• To verify theoretical research results on wireless mesh networks, extensive experimentation is needed. Yet it is often difficult to test a new algorithm on existing wireless devices, due to the lack of control on fine PHY/MAC attributes. We collaborate with the Champaign-Urbana Community Wireless Network (CUWiN) to substantially extend its mesh networking software, such that new APIs are defined, allowing upper-layer protocols to gain control of PHY/MAC attributes, including transmission power, data rate, contention window, and wireless channel, at different granularities such as per interface, per neighbor and per packet.

For more information on this project, please visit the Dynamic Ad-hoc Wireless Networks (DAWN) Project page in the INDEX Group website.

Study Group 2005 Summer at CUHK

• Access Pricing and Scaling for Wireless Mesh Networks | Reference paper

Study Group 2004 at CUHK

• WiFi Access Pricing as a Dynamic Game | Reference paper
• Dynamic Clustering for Acoustic Target Tracking in Wireless Sensor Network | Slides | Reference paper

Study Group 2003 Summer at CUHK

• The k-server Problem | Slides
• An Introduction to DDoS and the Trinoo Attack Tool | Slides

Coursework

My undergraduate major is Internet Engineering, which is an interdisplinary study involving Computer Science and Electrical Engineering, with a focus on computer networks.

My graduate coursework is listed as follows:

2006 Fall at UIUC

• CS 423-S4 Operating Systems Design
• ECE 567-C Communication Network Analysis

2005 Fall at CUHK

• CSC5420 Computer System Performance Evaluation

2005 Spring at CUHK

• CSC6200 Advanced Topics in Artificial Intelligence
  

2004 Fall at CUHK

• CSC5350 Game Theory in Computer Science
• CSC5480 Distributed Multimedia & Networks

Teaching

I was a teaching assistant at CUHK from 2004 to 2006. During my service, I was conferred the Merit for Excellent Teaching Assistantship for three semesters and was named the Best Teaching Assistant in 2006.

Here lists the courses that I have been the tutor of :

Professional Activities

• Reviewer, IEEE PerCom, 2007
• Web Editor, INDEX Group, UIUC, 2006