Research

Research interests

Internet measurement technologies, Large-scale network performance monitoring and diagnosis, Mobile and Wi-Fi network performance monitoring, Crowdsourcing for QoE and QoS measurement, Internet video QoE measurement, big data analytics and visualization for network traffic.

"Design and Implementation of a Unified Box for Offering Network Path Measurement as a Service," Funded by the Innovation and Technology Commission (under the Guangdong-Hong Kong Technology Cooperation Funding Scheme, Platform Research), June 2012 to May 2014 (total project cost: HKD $4,963,700).
"Reliable and Accurate Bandwidth Measurement of Asymmetric Network Paths," Funded by the Innovation and Technology Commission (under the ITSP tier-three programme), March 2010 - August 2011 (total project cost: HKD $967,150).
"Performance Monitoring and Measurement of HARNET," Funded by the The Joint Universities Computer Centre, January 2009 to December 2011.
"Uncooperative Measurement and Monitoring of Internet Path Quality with Applications," Funded by the Innovation and Technology Commission (under the ITSP tier-three programme), September 2008 to February 2010 (total project cost: HKD $999,350).
"Area of Excellence in Information Technology." Funded by the University Grants Council of Hong Kong, December 2004 to December 2005.
"Toward a General Approach to Per-queue Stability Problems with Applications in Wireless Communications." Funded by the Competitive Earmarked Research Grant, December 2001 to November 2004.

"Practical Monitoring and Troubleshooting Cross-domain Network Paths with a Single Monitor," Funded by The Hong Kong Polytechnic University Central Research Grant, October 2014 - November 2016 (total project cost: HKD $105,000).
"BGP-based Inbound Traffic Engineering for Multihomed Autonomous Systems: A Measurement-based Analysis." Funded by The Hong Kong Polytechnic University Central Research Grant, September 2004 to August 2006.
"Early Detection of Flash Crowds: A Nonparametric Approach." Funded by The Hong Kong Polytechnic University Central Research Grant, September 2003 to August 2005.

Ricky Mok, Rocky K. C. Chang, and Weichao Li, "Detecting low-quality workers in QoE crowdtesting: A worker behavior based approach," To appear in IEEE Trans. Multimedia.
Weichao Li, Daoyuan Wu, Rocky K. C. Chang, and Ricky Mok, "Demystifying and Puncturing the Inflated Delay in Smartphone-based WiFi Network Measurement," Proc. ACM CoNEXT, Dec. 2016.
Peter Membrey, Darryl Veitch, and Rocky K. C. Chang, "Time to Measure the Pi," Proc. ACM IMC, Oct. 2016. [Paper]
Ricky K. P. Mok, Weichao Li, and Rocky K. C. Chang, "IRate: Initial Video Bitrate Selection System for HTTP Streaming," IEEE JSAC (SI on Measuring and Troubleshooting the Internet: Algorithms, Tools and Applications), June 2016. [Paper]

"Network Measurement Research in a Complex Networked World (在複雜網絡世界中的網絡測量研究)" A keynote speech at Internet Conference of China (第二届中国互联网学术年会), 10 July 2013. [ppt]
"My Research Students and I," School of Computer, National University of Defense Technology, 9 July 2013. [ppt]