Mobile Computing       


Mobile Computing - Seminars

Title: Push and Pull Flows with Content-Based Addresses In Information-Centric Networks
Speaker: Antonio Carzaniga (Associate Professor, University of Lugano, Switzerland)
Host: Bongjun Ko (
Time: 11:00 AM, Monday, January 7th, 2013
Location: YKT 40-200


An information-centric network addresses data rather then hosts. This is a more natural way to access information for many applications, and it also leads to a more effective use of network resources since it seamlessly incorporates caching into the network. I have argued that an information-centric network should natively support content-based publish/subscribe event notification in addition to on-demand named-content delivery. I have also argued that both primitives could use the same forwarding information base and, furthermore, that both primitives can easily support content-based addresses that are more expressive than simple hierarchical names. In this talk, I will present a routing scheme that demonstrates this: "push" as well as "pull" communication; anycast as well as multicast; and true content-based (as opposed to name-based) addressing. The scheme is founded on multiple tree covers that can be arranged and composed hierarchically following the structure of network domains. On each tree, the scheme combines content-based addresses so as to reduce forwarding state. Starting from this particular routing scheme, I will then discuss the fundamental issue of address aggregation and more generally of the scalability of routing and forwarding state in information-centric networks.

Title: Fully Decentralized Estimation of Some Global Properties of a Network
Speaker: Antonio Carzaniga (Associate Professor, University of Lugano, Switzerland)
Host: Ting He (
Time: 10:00 AM, Monday, January 7th, 2013
Location: YKT 40-100


It is often beneficial to architect networks and overlays as fully decentralized systems, in the sense that any computation (e.g., routing or search) would use only local information, and no single node would have a complete view or control over the whole network. Yet it might still be necessary to compute global properties of the network. In this talk, I will present a fully decentralized algorithm to compute some global properties of a network that can be derived from the spectrum of the network. More specifically, the algorithm computes the most significant eigenvalues of a descriptive matrix closely related to the adjacency matrix of the network graph. Such spectral properties can then lead to, for example, the "mixing time" of the network, which is an important parameter of random walks and related search algorithms. The key insight is to view the network as a linear dynamic system whose impulse response can be computed efficiently and locally by each node. This impulse response can then be used to identify the spectral properties of the network. This algorithm is completely decentralized and requires only minimal local state and local communication. I will present experimental results that show that the algorithm works well on different kinds of networks and also in the presence of network instability.
Mobile PIC Seminar: Envisioning Tomorrow's Apps
Time: 10am-11am, THU, 29 NOV 2012
Location: Yorktown 20-043
Call-in: TBD
Envisioning Tomorrow's Apps

Mobile devices are becoming a convergent platform for sensing, computing, and communications. This talk will describe our attempts to jointly harness these capabilities, thereby enabling new classes of personal and collaborative applications. We will specifically focus on the opportunities and challenges at the intersection of multi-modal sensing, cloud computing, and data analytics, and describe how carefully fusing them can lead to powerful apps. We will close not only with challenges we are struggling with, but will also discuss new kinds of problems that will gain relevance in the days to come.

Romit Roy Choudhury is an Associate Professor of ECE and CS at Duke University. He joined Duke in Fall 2006, after completing his PhD from UIUC. His research interests are in wireless protocol design mainly at the PHY/MAC layer, and in mobile computing at the application layer. Along with his students, he received a few research awards, including the NSF CAREER Award, the best paper at Personal Wireless Communications conference, Hoffmann Krippner Award for Engineering Innovations, MobiCom Student Research Contest, etc. Visit Romit's Systems Networking Research Group (SyNRG), at
OS/Mobile PIC Seminar
Speaker: Professor Kang G. Shin Keving & Nancy O'Conor Professor of Computer Science, University of Michigan, Ann Arbor
Host: Kyung Ryu (Exascale System Software Research Group)
Date/Time: Friday, November 2, 2012, 11:00 AM - 12:00 PM
Room: Yorktown 20-001 (Dial-in: 1-888-426-6840, passcode: 76498553)
* If you would like to have a one-on-one meeting with the speaker on Friday, please contact the host.

WiFi interface is known to be a primary energy consumer in mobile devices, and idle listening (IL) is the dominant source of energy consumption in WiFi. Most existing protocols, such as the 802.11 power-saving mode (PSM), attempt to reduce the time spent in IL by sleep scheduling. However, through an extensive analysis of real-world traffic, we found more than 60% of energy is consumed in IL, even with PSM enabled.
To remedy this problem, we propose E-MiLi (Energy-Minimizing idle Listening) that reduces the power consumption in IL, given that the time spent in IL has already been optimized by sleep scheduling. Observing that radio power consumption decreases proportionally to its clock-rate, E-MiLi adaptively downclocks the radio during IL, and reverts to full clock-rate when an incoming packet is detected or a packet has to be transmitted. E-MiLi incorporates sampling rate invariant detection (SRID), ensuring accurate packet detection and address filtering even when the receiver's sampling clock-rate is much lower than the signal bandwidth. Further, it employs an opportunistic downclocking mechanism tooptimize the efficiency of switching clock-rate, based on a simple interface to existing MAC-layer scheduling protocols. We have implemented E-MiLi on the USRP software radio platform. Our experimental evaluation shows that E-MiLi can detect packets with close to 100% accuracy even with downclocking by a factor of 16. When integrated with 802.11, E-MiLi can reduce energy consumption by around 44% for 92% of users in real-world wireless networks.

Professor Kang G. Shin:
KANG G. SHIN is the Kevin & Nancy O'Connor Professor of Computer Science in the Department of Electrical Engineering and Computer Science, The University of Michigan, Ann Arbor. His current research focuses on computing systems and networks as well as on embedded real-time and cyber-physical systems, all with emphasis on timeliness, security, and dependability. He has supervised the completion of 73 PhDs, and authored/coauthored about 800 technical articles (about 300 of these are in archival journals), one textbook and more than 20 patents or invention disclosures, and received numerous best paper awards, including the Best Paper Awards from the 2011 ACM International Conference on Mobile Computing and Networking (MobiCom’11), the 2011 IEEE International Conference on Autonomic Computing, the 2010 and 2000 USENIX Annual Technical Conferences, as well as the 2003 IEEE Communications Society William R. Bennett Prize Paper Award and the 1987 Outstanding IEEE Transactions of Automatic Control Paper Award. He has also received several institutional awards, including the Research Excellence Award in 1989, Outstanding Achievement Award in 1999, Distinguished Faculty Achievement Award in 2001, and Stephen Attwood Award in 2004 from The University of Michigan (the highest honor bestowed to Michigan Engineering faculty); a Distinguished Alumni Award of the College of Engineering, Seoul National University in 2002; 2003 IEEE RTC Technical Achievement Award; and 2006 Ho-Am Prize in Engineering (the highest honor bestowed to Korean-origin engineers).
Mobile PIC Seminar: Human Mobility Characterization from Cellular Network Data
Time: 10am, Wednesday, 21 March 2012
Location: Hawthorne 1S-F40
Call-in: 888-426-6840 or 215-861-6239
Passcode: 3629497

An improved understanding of human mobility patterns would yield insights into a variety of important societal and urban planning issues. Location information from cellular wireless networks has great potential as a tool for studying these patterns. In this talk, I describe how we used anonymous and aggregate location data to study people's daily commutes, identify important places people visit, calculate people's carbon footprints and infer relative traffic volumes on city roads.

Alexander Varshavsky is a Senior Member of Technical Staff at AT&T Labs. His research interests include mobile and ubiquitous computing, context-awareness and security in mobile systems. He holds a Ph.D. in Computer Science from the University of Toronto, Canada.

If you would like to meet with Alex after the talk, please contact the host, Paul Castro.
Title: Real-time Mobile Sensing/Analytics and the LiveLabs Experimentation Platform
Speaker: Prof. Archan Misra, School of Information Systems, Singapore Management University
Host:Arup Acharya, IBM Research
When: Thursday March 8, 2012 11 am - noon ET
Where:Room GN-K35, Hawthorne

Abstract: This talk will introduce the LiveLabs Experimentation Platform, a unique 5-year “urban behavioral testbed” project starting at SMU. LiveLabs combines innovations in wireless networks, mobile sensing and Apps to enable an ecosystem of industry partners to test next-generation context-based applications on approx. 30,000 real-life users in urban spaces, including as the SMU campus, 2 major shopping malls and a resort theme park. LiveLabs’ research thrusts include the enablement of fine-grained continuous mobile sensing, real-time network adaptation for traffic hotspots in urban spaces and a software infrastructure for automated deployment, monitoring and measurement of mobile applications/experiments. I will briefly review ongoing projects around the energy-efficient sensing of such rich context and the use of such context to: a) optimize the delivery of mobile advertising and b) real-time adaptation of femto-cellular indoor networks.

Short Bio: Archan Misra is currently an Associate Professor of Information Systems at Singapore Management University (SMU) and also has administrative responsibilities for two major research centers/projects: the CMU-SMU Living Analytics Research Center (LARC) and the LiveLabs National Innovation Platform. His current research interests are in pervasive computing & mobile systems, with specific focus on energy-efficient analytics for mobile sensing, advanced indoor localization and hybrid cloud+P2P middleware for context-based mobile applications. Over the past 11 years (as part of his previous employment with IBM Research and Telcordia Technologies), he has worked in the areas of wireless networks, pervasive computing and sensor stream data management and is a co-author on papers that received the Best Paper awards in EUC 2008, ACM WOWMOM 2002 and IEEE MILCOM 2001. Archan received his Ph.D. in Electrical and Computer Engineering from the University of Maryland at College Park and his B.Tech in Electronics and Communication Engineering from IIT Kharagpur, India.

Call-in : 1-888-426-6840 Passcode : 8037019 Lotuslive:
Title: PhoneLab: A Large-Scale Participatory Smartphone Testbed
Speaker: Prof. Steve Ko (University of Buffalo)
Host: Kang-Won Lee, Manager, Wireless Networking Department, IBM Research
When: Monday March 12, 2012
Where:10:00 - 11:30 am ET Room 1S-F40, Hawthorne
Dial-in : USA Toll-Free: 888-426-6840
For Other Countries:
Participant Code: 81887305

The expanding capabilities and growing number of smartphones are†producing a new computing paradigm integrating phones, users, and the†cloud. Users now expect their phones to locate friends; identify the†song playing at a restaurant; provide instant access to music, video,†and other information; and help document their lives all in addition†to placing phone calls and sending text messages. Meeting these†expectations requires addressing multiple challenges: efficiently†utilizing multiple radio technologies and integrated sensors,†harnessing powerful processors to support demanding applications, and†leveraging distributed storage to move data closer to users. Yet,†despite the challenges and transformative nature of the phone cloud,†no public testbed exists enabling large-scale realistic smartphone†experimentation.

In this talk, I will talk about PhoneLab, a new testbed enabling smartphone†operating system and mobile application research in a realistic†environment at a scale not previously possible. PhoneLab will†eventually consist of 1,000 reprogrammable Android devices deployed†into the hands of students and staff at SUNY at Buffalo, providing the†flexibility, scale, and realism necessary to enable mobile computing†research.

In addition, I will also talk about a few projects I am doing in the domain of smartphones including security and privacy, location tracking, and networking.

Short Bio: Prof. Steve Ko is an Assistant Professor at University of Buffalo, The State†University of New York.†He received his†Ph.D. from the University of Illinois at Urbana-Champaign in 2009†under the guidance of Prof. Indranil Gupta.†Before joining UB, He spent a year as a†Postdoctoral Research Associate at Princeton University working with†Prof. Jennifer Rexford and Prof. Michael Freedman. †He is generally interested†in distributed systems and networking, with an emphasis on data center†technologies and smartphones. His current research focuses on the†intersection between cloud computing and smartphones including†security and privacy issues, testbed design, and storage. In the past,†he has worked on storage support for fault-tolerant MapReduce, data†center monitoring, Grid scheduling algorithms, and fault-tolerant†peer-to-peer algorithms.

Date: 11/11/2011, Fri
Time: 10-11:00 AM ET
Location: 1N F28
Host: Fan Ye
USA Toll-Free: 888-426-6840
Participant Code: 56865775

Title: "Localization for Sensornets"


Wireless Sensor Network (WSN) systems have been used in many promising applications including military surveillance, habitat monitoring and wildlife tracking. While many middleware services to support these applications have been designed and implemented successfully, node localization - finding the position of a sensor node -remains one of the most difficult and important research challenges to be solved in practical settings. In this talk, we explain first why the existing range-based and range-free localization methods are inadequate to meet low-cost and high accuracy requirement simultaneously. To address this limitation, we present several localization techniques which achieves high accuracy with low cost. The limitations and advantages of these new technologies shall be discussed during the talk.


Dr. Tian He is currently an associate professor in the Department of Computer Science and Engineering at the University of Minnesota-Twin City. He received the Ph.D. degree under Professor John A. Stankovic from the University of Virginia, Virginia in 2004. Dr. He is the author and co-author of over 100 papers in premier sensor network journals and conferences with over 7000 citations. His publications have been selected as graduate-level course materials by over 50 universities in the United States and other countries. Dr. He has received a number of research awards in the area of sensor networking, including four best paper awards. Dr. He is also the recipient of the NSF CAREER Award 2009 and McKnight Land-Grant Professorship. Dr. He served a few program chair positions in international conferences and on many program committees, and also currently serves as an editorial board member for four international journals including ACM Transactions on Sensor Networks. His research includes wireless sensor networks, intelligent transportation systems, real-time embedded systems and distributed systems, supported by National Science Foundation, IBM, Microsoft and other agencies.
Date: Tuesday Aug.23 2011
Time: 10 AM
Location: GN-K35
Host: James Christensen

Title: Crowdsourced Sensing and Collaboration using Smartphones and Social Networks

Abstract: While smartphones and social networks provide a suitable platform for ubiquitous communication and computation, the state-of-the-art fail short of the ubiquitous computing vision. We argue that this gap is due to the lack of a framework to utilize these tools for crowdsourced collaboration and social coordination. In this talk, I'll explain how smartphones and social networks can help to fulfill the ubiquitous computing vision. The talk will illustrate the three projects that I've been worked/working on: CrowdReply: which investigates the feasibility of answering location-based queries by crowdsourcing over Twitter. TrendSensing: which presents a passive sensing framework for identifying trends via Twitter. UBUpdates: which is a social crowdsourcing platform on smartphones.

Bio: Muhammed Fatih Bulut is a 2nd year PhD student in Ubiquitous Computing Lab at University at Buffalo (UB). Prior to coming to UB, he took his B.S. from Bilkent University in Turkey with high honor degree. His research interest are broadly on Crowdsourcing, Social Networks and Smartphones.

Date: 6/2/11, Thu
Time: 11-12PM
Location: 4S K21
Host: Fan Ye

Speaker: Prof. Yingying Chen, ECE, Stevens Institute of Technology

Title: Performing Joint Learning for Passive Intrusion Detection in Pervasive Wireless Environments

Recent years have witnessed increasing interests in passive intrusion detection for wireless environments, e.g., asset protection in industrial facilities and emergency rescue of trapped people. Most previous studies have focused primarily on exploiting a single intrusion indicator, such as moving variance, for capturing an intrusion pattern at a time. However, in real-world, there are many intrusion patterns which may be only detectable by combining different intrusion indicators and performing detection jointly. To this end, we propose a joint intrusion learning approach, which has the ability in combining the detection power of several complementary intrusion indicators and detects different intrusion patterns at the same time. Our algorithm grounded on grid-based clustering over K-neighborhood can effectively diagnose the presence of intrusions. Further, we show that the performance of intrusion detection can be enhanced by utilizing the collaborative detecting efforts among multiple transmitter-receiver pairs. To validate the effectiveness of the joint intrusion learning method, we conducted experiments in a real-office environment using an IEEE 802.15.4 (Zigbee) network. Our experimental results provide strong evidence of the effectiveness of our joint learning approach in performing passive intrusion detection with a minimized false positive rate.

Yingying Chen received her Ph.D. degree in Computer Science from Rutgers University. She is currently an assistant professor in the Department of Electrical and Computer Engineering at Stevens Institute of Technology. Her research interests include information security and privacy, wireless and sensor networks, and mobile social networks. She has coauthored the book Securing Emerging Wireless Systems and published extensively in journal and conference papers. Prior to joining Stevens Institute of Technology, she was with Bell Laboratories and the Optical Networking Group, Lucent Technologies. She received the IEEE Outstanding Contribution Award from IEEE New Jersey Coast Section each year 2005-2009. She is the recipient of the NSF CAREER award. She received Google Research Award 2010. She is also the recipient of the Best Technological Innovation Award from the International TinyOS Technology Exchange in 2006, as well as the Best Paper Award from the International Conference on Wireless On-demand Network Systems and Services (WONS) in 2009.

Date: 1/28/11, Fri
Time: 10-11AM
Location: 4S K21
Host: Raghu Ganti

Professor John A. Stankovic, Department of Computer Science, University of Virginia
Abstract: Wireless sensor networks (WSN) composed of large numbers of small devices (called motes or dust) can self-organize and be used for a wide variety of applications. In particular, these systems can be used to improve the quality of health care, be applied in the home or in large-scale assisted living facilities, and significantly contribute to longitudinal studies. I will present, AlarmNet, a novel system for assisted living and residential monitoring that uses front-end body networks, intermediate environmental sensing and communication networks, and back-end context aware protocols that are tailored to residents’ individual living patterns. In the back-end, a program has been implemented to infer behaviors and use that information for improved health care. For example, these programs infer medical issues such as depression. In this talk I will describe the overall AlarmNet architecture, various front-end body networks, the intermediate sensor network, and the back-end databases and analysis. Key issues addressed include: flexible and evolvable heterogeneous configurations, privacy, robustly detecting falls, measuring sleep motion and quality, and a real-time query system.

Brief Bio: Professor John A. Stankovic is the BP America Professor in the Computer Science Department at the University of Virginia. He served as Chair of the department, completing two terms (8 years). He is a Fellow of both the IEEE and the ACM. He won the IEEE Real-Time Systems Technical Committee's Award for Outstanding Technical Contributions and Leadership. He also won the IEEE Distributed Processing Technical Committee’s Award for Distinguished Achievement (inaugural winner). He has won four best paper awards in wireless sensor networks research. Professor Stankovic also served on the Board of Directors of the Computer Research Association for 9 years. Recently, he won the University of Virginia, School of Engineering Distinguished Faculty Award. Before joining the University of Virginia, Professor Stankovic taught at the University of Massachusetts where he won an outstanding scholar award. He was the Editor-in-Chief for the IEEE Transactions on Distributed and Parallel Systems and was a founder and co-editor-in-chief for the Real-Time Systems Journal for 18 years. His research interests are in wireless sensor networks, cyber physical systems, distributed computing, and real-time systems. Prof. Stankovic received his PhD from Brown University.