Dong Han
Network Systems Laboratory
Department of Computer Science
University of Houston

donny at cs dot uh dot edu

Recent Research Projects:

Revealing Protocol Information and Activity from Energy Instrumentation in Wireless Sensor Network
We trying to propose a novel approach to study and reveal network and protocol information from energy instrumentation in wireless sensor network. Unlike prior approaches which focused on analyzing the aggregate statistics of energy efficiency of a network or a protocol, our approach aims at revealing network protocols, application workloads, and topology information by fine-grained energy instrumentation on the nodes. We design a set of features based on various aspects of energy data and use those features to classify and reveal network activity. Results from experiments on two testbeds indicate that our approach can achieve up to 95% accuracy to identify the routing protocols, and infer the network topology with 80% accuracy on average.

Performance Evaluation/Analysis of RPL in environment with High Noise.
Smart homes and environments will consist of a large number of low power wireless devices such as sensors and actuators. Recently IETF standardized a network protocol called RPL that is designed to run on these nodes. In this article, we study the performance of RPL on a variety of scenarios that these nodes will encounter when they are deployed in practice. We deploy a network of 23 sensor nodes in a computer lab to monitor energy use by each computer across the applications and users. We subject the network to four different levels of interference that are representative of the types and levels of interference that these networks might encounter in deployment. Our study finds that RPL’s reliability degrades even with an access point in overlapping channel under normal network traffic. With high interference, the packet delivery reliability goes down to 10%. The scenario that resulted in this performance is not unimaginable in smart home or environment. This performance degradation is partly due to lack of coordination across the layers of the protocol stack: RPL is unaware of the changes in the wireless environment underneath and proceeds as usual. As other research has shown, coordination across the network stack is essential for network protocols to work reliably in the presence of interference. This will require a more coordinated approach to standards across the bodies.

Power measurement academic laboratory.
In this project, we present results from our measurement and analysis of energy use and user behavior in an academic computer lab. We use wireless power sensors to collect power readings from 22 computers in the lab. We use software monitor to log various user activities in the computer. We collected a total of 59.6 million power readings and 220.3 million user activity logs over one month. We analyze the data collected from this instrumentation to not only understand how much energy is used but to also drill down and reveal a detailed understanding of which machines, processes, and users contribute the most to computing energy footprint of the lab. Our results show the power draw on different machines in the lab are different despite the identical hardware and software settings. Our study attributes this difference to different users presenting different types and lengths of load to the computers, preferring specific physical computers, which leads to some computer being used more than others. The results show that the majority of energy was wasted while the computer was left in idle mode, and individual user behavior affects the energy consumption.

List of Publications


Abhishek Murthy, Dong Han, Dan Jiang, Talmai B Oliveira; Lighting-Enabled Smart City Applications Ecosystems Based on the IoT, In Proceedings of the 2015 IEEE 2nd World Forum on Internet of Things (WF-IoT), Dec. 2015.

Dong Han, Omprakash Gnawali, and Abhishek Sharma; Revealing Protocol Information and Activity from Energy Instrumentation in Wireless Sensor Network, In Proceedings of the 12th European conference on Wireless sensor networks (EWSN 2015), Feb. 2015.

Muhammad Hamad Alizai, Muhammad Moosa, Dong Han, Omprakash Gnawali, and Affan Syed; Recycling Corrupt Packets over Multiple Hops, In Proceedings of the 12th European conference on Wireless sensor networks (EWSN 2015), Feb. 2015.

Dong Han, Omprakash Gnawali; Performance of RPL Under Wireless Interference. IEEE Communications Magazine, vol. 51, no. 12, December 2013. Magazine Impact Factor: 4.46

Dong Han, Omprakash Gnawali; Understanding Desktop Energy Footprint in an Academic Computer Lab . The IEEE International Conference on Green Computing and Communications (GreenCom 2012), 2012.

Guanbo Zheng, Dong Han, Rong Zheng; Schmitz, C., Xiaojing Yuan; A Link Quality Inference Model for IEEE 802.15.4 Low-Rate WPANs . IEEE Global Telecommunications Conference (GlobeCom), 2011

Wei Sun, Xiaojing Yuan, Jianping Wang, Dong Han, Chongwei Zhang; Quality of Service Networking for Smart Grid Distribution Monitoring . First IEEE International Conference on Smart Grid Communications (SmartGridComm), 2011

Balakrishnan, M., Dong Han, Benhaddou, D., Xiaojing Yuan; End-to-end QoS in integrated wireless and sensor network: System implementation . 7th International Symposium on Communication Systems Networks and Digital Signal Processing (CSNDSP), 2010

Book Chapter

Xiaojing Yuan, Wei Sun, Dong Han, Jianping Wang, Chongwei Zhang, Xiaohui Yuan; Quality of Service in Networking for Smart Grid , Chapter 10 in Communication and Networking in Smart Grids, edited by Yang Xiao, CRC Press, 2012

Poster / Demo

Dong Han, Omprakash Gnawali, Abhishek Sharma; Understanding Radio Activity Signature of Wireless Sensor Network Protocols. In ACM Conference on Embedded Networked Sensor Systems (SenSys 2014), November 2014. (Poster)

Qiang Li, Dong Han, Omprakash Gnawali, Philipp Sommer, Branislav Kusy; Twonet - Large-Scale Wireless Sensor Network Testbed with Dual-Radio Nodes. In ACM Conference on Embedded Networked Sensor Systems (SenSys 2013), November 2013. (Demo)

Pervious Teaching Assistant:

COSC 4377: Introduction to Computer Networks
ELET 3404: Sensors and Applications
ELET 4300: Unix Operating System
ELET 6318: Analysis of Data Networks