Tag Archives: Baek-Young Choi

SCE student/faculty researchers win prestigious award for mobile app, WiFi-Honk

With all judges agreeing, the mobile app, WiFi-Honk, developed by SCE faculty and student researchers received the Best Video Award at the ACM Mobisys 2014 conference, a highly selective and premiere conference in mobile computing.  The committee included renowned researchers from academia and industries such as Google and Microsoft Research.

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Four SCE Women Graduate Students Receive GAF Awards

Four talented UMKC SCE women graduate students have been selected to receive UMKC Women’s Council Graduate Assistant Fund (GAF) Awards.  These competitive awards are based on the merits of their proposed projects and/or scholarly activities. Lean more about how their efforts will be making a difference.   

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SCE Faculty Host Regional Security Workshop


Drs. Baek-Young Choi and Deep Medhi, professors at the UMKC School of Computing and Engineering, recently hosted KanSec, a regional security workshop, on Saturday, Nov 2nd at Pierson Auditorium on UMKC’s campus.

The workshop brought together 65 researchers and practitioners from 18 institutions and 7 states. Participants were able to share new developments and discuss ideas pertaining to computer and communication security.  The program also included two keynote speeches, nine paper presentations, an industry panel, and a poster session.

During the workshop, several research projects on cloud and smartphone security were presented, and a panel discussion provided insightful perspectives on preventing next generation DoS (Denial of Service) attacks.

SCE Students Winners in Poster Contest at MINK WIC Conference

UMKC School of Computing and Engineering students Xinjie Guan and Victoria Wu recently received awards for their research posters at the Missouri, Iowa, Nebraska and Kansas Women in Computing (MINK WIC) Conference.

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Kaustubh Dhondge Receives 1st Place Outstanding Graduate Poster Presentation Award at GPN 2013 Annual Meeting

SCE’s Kaustubh Dhondge showcased his research paper, FUEL: Fast, Ubiquitous, Easy-to-use, and Low-cost Authentication for Smartphones, a “scheme for authenticating users by leveraging existing ambient light sensors on smartphones”, at the May 29-31, 2013 GPN (Great Plains Network) 2013 Annual Meeting. His research, conducted with Hyungbae Park and his advisor Dr. Baek-Young Choi, has resulted in a prototype that “utilizes a light sensor available on smartphones and a low-cost hardware token in order to authenticate a user of a smartphone to unlock it or to allow access to web and cloud services.” Continue reading

Ph.D. Student Xinjie Guan selected for GHC Research Scholarship

Selected from a competitive pool of over 1000 applicants, SCE Computer Science Ph.D. student Xinjie Guan has been awarded an ISOC (the Internet Society) scholarship to present her research at the 2012 Grace Hopper Celebration of Women in Computing (GHC) being held October 3-6, 2012 in Baltimore, MD. Xinjie Guan’s poster session, “Push or Pull?: Toward Optimal Content Delivery using Cloud Storage”, will showcase the novel distributed algorithm, named Bandwidth-Latency-Minimization (BLM), which she developed under the direction of her faculty advisor, Dr. Baek-Young Choi. Real experiments as well as simulations have shown that the BLM significantly optimizes content delivery using cloud storage for video-over-IP applications. Academic achievement, potential in the field, need and thoughtful, creative, well-written essays were part of the selection criteria used by GHC to determine this year’s poster session participants. Congratulations Xinjie!


Abstract: Cloud computing and ‘Storage As A Service’ (SaaS) are experiencing a momentous popularity increase due to its flexible, and scalable access to resources. Especially, cloud storage is becoming an economical alternative to traditional content delivery networks (CDNs) such as Akamai and Limelight Networks for moderate-size content providers. Previous research on content distribution mainly focuses on reducing latency experienced by content customers. A few recent studies address the issue of bandwidth usage in CDNs, as the bandwidth consumption is an important issue due to its relevance to the cost of content providers. However, few works consider both bandwidth consumption and delay performance for the content providers that use cloud storage with limited budgets, which is the focus of this paper. We develop an efficient light-weight approximation algorithm toward the joint optimization problem of content placement. We also conduct the analysis of its theoretical complexities. The performance bound of the proposed approximation algorithm exhibits a much better worst case than those in previous studies. We further extend the approximate algorithm into a distributed version that allows it to promptly react to dynamic changes in users’ interests. The extensive results from both simulations and Planetlab experiments exhibit that the performance is near optimal for most of the practical conditions.

Significance: Video-over-IP applications are experiencing a momentous popularity increase via crowd-acceleration. Content delivery using distributed caching on cloud storage, such as Amazon Simple Storage Services, can alleviate high bandwidth demands of such applications and can significantly cut down the costs in building and maintaining servers comparing with traditional Content delivery networks. However, the latency experienced by content users and the cost of provisioning VoIP services including bandwidth and storage space are heavily depended on content placement and delivery strategies. Few prior researchers have considered saving bandwidth consumption together with latency performance in neither traditional CDNs nor cloud storage. Our work aims to optimize the content delivery using cloud storage.

Publications: A preliminary version of this work was published in International Conference on Communication (ICC) 2011. It has now been extended with a novel distributed algorithm for cloud storage; and the scheme has been extensively evaluated using Planetlab testbed.

Baek-Young Choi Spends Summer at Air Force Research Laboratory

Dr. Baek-Young Choi worked on an energy-efficient cooperative and opportunistic positioning system for heterogeneous mobile devices at the United States Air Force Research Laboratory (AFRL) located in Rome, NY during the 2012 summer break. She has also been working on a book titled ‘High Performance Semantic Cloud Auditing’ with collaborators at the AFRL. The fast growing popularity of smartphones and tablets enables us the use of various intelligent mobile applications. Many of those applications require position information which smart mobile devices provide using positioning methods such as GPS, WiFi, or Cell-ID based positioning services. These positioning methods have different characteristics of energy efficiency, accuracy, and service availability. Her work is to combine those positioning methods for resource-constrained environments. While at the AFRL, Dr. Choi gave a couple presentations on site and at an Air Force bi-annual conference, the Cyber and Information Challenges Conference, in Utica, NY.

Kaustubh Dhondge & Hyungbae Park win poster award at GPN conference

Kaustubh Dhondge & Hyungbae Park won the second place student poster award for their poster, “Energy-Efficient Cooperative Opportunistic Positioning for Heterogeneous Mobile Devices”, presented at the Great Plains Network (GPN) Conference, held in Kansas City, Missouri from May 30 to June 1, 2012. Kaustubh Dhondge also presented the paper at the Graduate Student Networking Research Summit. Both Mr. Dhondge and Mr. Park are Ph.D students at UMKC SCE studying computer science, telecommunications and networking disciplines. They have developed an energy-efficient system for mobile devices to obtain their geographic location information. This work (ECOPS) was developed for and tested on Android powered mobile devices. In ECOPS, unlike any other existing approaches the mobile devices cooperate with each other autonomously to know their actual geographic location without any dependence on infrastructure. The experiments to validate its energy efficiency and location accuracy were done at the UMKC soccer field and found that ECOPS provides location accuracy as good as 5 m, and with significantly more energy efficiency than a GPS only scheme, while overcoming various service limitations.

Their research and resulting applications are helping remove universal limitation of smart devices– poor battery life. When smart devices are used in mission critical environments like battlefields, mountaineering expeditions and disaster area assistance, the need for judicious battery usage becomes even more compounded. Kaustubh Dhondge’s & Hyungbae Park’s goal in doing this research was to design a system for these smart devices that provides highly accurate location information while significantly using less energy consumption versus the traditional approach of each device using their own inbuilt GPS. For example, in a battlefield environment this approach will increase the operational time of devices in the network which can make a difference between the success and failure of a mission and help protect soldier’s lives. The research was conducted under the guidance of their Ph.D. adviser, Professor Baek-Young Choi. The other faculty involved and guiding them in the work is Dr. Sejun Song who is with Texas A&M University.

Xinjie Guan & Xili Wan Awarded GENI Summer Camp Scholarships

Xinjie Guan and Xili Wan are two of ten students in the nation to win the first annual GENI (Global Environment for Network Innovations) summer camp scholarships. Ms. Guan, a third year telecommunications and networking Ph.D. student at UMKC SCE, and Mr. Wan, a fourth year telecommunications and networking Ph.D. student at UMKC SCE, spent May 29, 2012 – June 2, 2012 at the Rochester Institute of Technology in New York learning how to use the GENI resources/tools such as ProtoGENI, Flack, Instools, and OpenFlow. They gained hands-on lab experience with those resources and developed a team-based project that established certain network topology and investigated the impact of new flow attack to OpenFlow switch.

Attending the GENI summer camp greatly improved Ms. Guan’s and Ms. Wan’s skill in using GENI resources/tools. Furthermore, they obtained many significant suggestions from GENI experts on how to design and begin their next research projects. GENI infrastructure is becoming a mature virtual lab for networking related researches and compared to traditional simulation, GENI resources and tools provide more convincible results as they support experimentation on real nodes throughout the network. Xinjie Guan’s faculty advisor is Professor Baek-Young Choi and Xili Wan’s faculty advisor is Professor Xiaojun Shen. SCE heartily congrats Ms. Guan and Mr. Wan on their awards and knows the experience they have gained will benefit them greatly. For more detail about the camp download the file – GENI.

Deep Medhi & Baek-Young Choi local hosts for GEC12 Conference

UMKC is proud to host The 12th NSF Global Environment for Network Innovations (GENI) Engineering Conference (GEC12) that will take place November 2-4, 2011, in Kansas City, Missouri, at the Student Union Building The GEC is the National Science Foundation’s GENI Project Office’s (GPO) regular working meeting where researchers, developers, industrial & international partners and the GPO meet to advance infrastructure planning and prototyping for the GENI project on future networking. At this event, researchers from around the country will demonstrate their latest work on future networking prototypes. Pre-registration is required.

Evolving technological and social networks, intertwined and worldwide in scope, are rapidly transforming societies and economies. GENI is a project sponsored by the National Science Foundation, is open and broadly inclusive, providing collaborative and exploratory environments for academia, industry and the public to catalyze groundbreaking discoveries and innovation in these emerging global networks.

GENI is a virtual laboratory at the frontiers of network science and engineering for exploring future internets at scale. GENI creates major opportunities to understand, innovate and transform global networks and their interactions with society. Understand. Innovate. Transform – Make an Impact on Global Networks.

UMKC is involved in Great Plains Environment for Network Innovation (GpENI), one of the GENI funded projects. UMKC is partnering in the GpENI project with University of Kansas, Kansas State University, and University of Nebraska-Lincoln to set up an international research testbed for future network research. Deep Medhi, Curators’ Professor, and Baek-Young Choi, Associate Professor, are leading the effort at the UMKC end.