NOTE: The Center for Mobile Computing is no longer active, and this web site represents a historical view of its activities from 1996-2008. Although there is still mobile-computing research underway at Dartmouth, we no longer update this web site. Please contact David Kotz with any inquiries about the CMC.
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Congratulations to Udayan Deshpande, Kimo Johnson, Zhengyi Le, Ming Li, Soumandra Nanda, Yi Ouyang, Anna Shubina, Libo Song, and Yurong Xu (alphabetically ordered by last names) for receiving their Ph.D.s on June 8th, 2008!
Minho Shin recently earned his Ph.D degree in Computer Science from the University of Maryland in November 2007. His graduate research focused on the performance and the security of wireless networks. He received a B.S. degree in Computer Science and Statistics from the Seoul National University, Korea, in 1998 and a M.S. degree in Computer Science from the University of Maryland at College Park in 2003. He joins us as a Post-Doctoral Research Fellow with David Kotz in the ISTS-sponsored MetroSense project.
We expect that wearable, portable, and even embeddable medical sensors will enable long-term continuous medical monitoring for many purposes, such as patients with chronic medical conditions (such as the recently announced blood-sugar sensors for diabetics), people seeking to change behavior (e.g., losing weight, or quitting smoking), or athletes wishing to monitor their condition and performance. The resulting data may be used directly by the person, or shared with others: with a physician for treatment, with an insurance company for coverage, or by a trainer or coach. Such systems have huge potential benefit to the quality of healthcare and quality of life for many people.
Since the sensor data may be gathered through a patient's mobile device (such as a mobile phone), a wireless network, and the Internet, there are many opportunities for the sensor data to be tampered or otherwise inaccurate. How can we assess confidence in sensor data? How can we present that level of confidence, in context, with the sensor data? This project will develop methods to assess confidence in medical sensor data.
Funded by Intel University Research Council.
People: David Kotz, and students TBD.
All our best wishes to Dr. Libo Song, who defended his Ph.D thesis last month and days later started his new job at Bloomberg in NYC. Good luck, Libo!
Libo's dissertation will be added to the CMC web site once final revisions are complete, in a month or so. Below is the abstract of his dissertation: Evaluating Mobility Predictors in Wireless Networks
Handoff prediction in wireless networks has long been considered as a mechanism to improve the quality of service provided to mobile wireless usages. Most prior studies for the performance of prediction techniques, however, were based on theoretical analysis, simulation with synthetic mobility models, or small wireless network traces.
We tackle the problem by using traces collected at a large production wireless net-work to evaluate several major families of handoff-location prediction techniques (Markov, LZ-based, PPM and SPM predictors), a set of handoff-time predictors (Markov, Moving Average and CDF predictors), and a predictor that jointly predicts handoff location and time. We also propose a fallback mechanism, which uses a lower-order predictor whenever a higher-order predictor fail to predict.
We found that low-order Markov predictors, with our proposed fallback mechanisms, performed as well or better than the more complex and more space-consuming compression-based handoff-location predictors. Although our handoff-time predictor had modest prediction accuracy, in the context of mobile voice applications we found that bandwidth reservation strategies can benefit from the combined location and time handoff predictor for significantly reducing call-drop rate without significantly increasing the call-block rate.
We also developed a prediction-based routing protocol for mobile opportunistic net-works. We evaluated and compared our protocol's performance to five existing routing protocols, by simulations driven by real mobility traces. We found that the basic routing protocols are not practical for large-scale opportunistic networks. Prediction-based routing protocols trade off message delivery ratio against resource usage and performed well and comparable to each other.
All our best wishes to Dr. Yong Sheng, who received his Ph.D under George Cybenko at the Thayer School of Engineering and then joined the CMC's MAP project for a year-long postdoctoral fellowship. Yong starts next month in the China division of Google, based in Seattle. We will all miss his cheerful disposition and his many contributions to research in the CMC lab. Good luck, Yong!
He has 12 publications and 3 posters in the areas of intrusion detection for wireless sensor networks, localization, security and privacy. He was an honorable mention at a student research poster competition held at 7th Annual Information Security Symposium (by CERIAS at Purdue University). He was an honorable mention for an excellence in research award at the Department of Computer Science, Western Michigan University for two years 2004-2005 and 2005-2006.
He did internships at ABN Amro (Mumbai), Crompton Greaves (Mumbai) and Manatron (Portage, MI).
He is a member of UPE and served as a vice president of the local chapter at Western Michigan University in 2003-2004.
At the invitation of the Air Force Information Operations Center, and coordinated by HSARPA in the Department of Homeland Security, the MAP team took their demo on their road. The MAP project - "Measure, Analyze, Protect" aims to detect and respond to attacks on a production Wi-Fi wireless network on an enterprise scale. Since the MAP system is currently deployed throughout Sudikoff Lab for Computer Science, involving 20 wireless access points and two rack-mounted servers, it was no easy feat to make the demo portable! In the end, six laptops, four access points, and countless cables and accessories were shipped to San Antonio and set up at the host site - the Southwest Research Institute. Key researchers from the Air Force Information Operations Center, and guests from the Naval Research Lab (in Washington DC) attended. This demo was possible because of the tireless efforts of Yong Sheng, Keren Tan, Bennet Vance, and Udayan Deshpande. In February the MAP team demonstrated MAP to the US Secret Service in Miami, Florida.
Yong's thesis, entitled "The Theory of Trackability and Robustness for Process Detection," is available online athttp://www.dartmouth.edu/~ysheng/thesis/ysthesis.web.pdf
CALL FOR PARTICIPATION
CRAWDAD Workshop 2006
Community Resource for Archiving Wireless Data At Dartmouth
In Cooperation with ACM
SIGMOBILE
http://crawdad.cs.dartmouth.edu/workshop2006
September 25th, 1:30pm-6:00pm
Co-located with MobiCom in Los Angeles, CA, USA
CRAWDAD Workshop 2005 held at Mobicom
September 1, 2005
Auguest 11,2005
The CMC just launched a major new effort at Dartmouth College, a Community Resource for Archiving Wireless Data at Dartmouth (CRAWDAD).
NSF has funded this effort to build a community resource, an archive with the capacity to store wireless trace data from many contributing locations, with the staff to develop better tools for collecting, anonymizing, and analyzing the data. This Community Resource for Archiving Wireless Data At Dartmouth, CRAWDAD, will work with community leaders to ensure that the archive meets the needs of the research community, work with the other leading centers that develop network tracing tools and metadata, and work with research organizations and corporations to ensure continuing support for the archive after NSF's funding ends.
July 2, 2005
After several years on the
faculty at Columbia University, Andrew Campbell is moving to
Dartmouth College as an Associate Professor of Computer Science.
Andrew brings to the CMC his long track record in mobile
computing and wireless networking, and looks forward to working
with CMC faculty and students on a variety of new projects.
Andrew is investigating the synthesis between the demands of highly dynamic systems (e.g., mobile and wireless systems), the need to embed better service creation engines into the network infrastructure, and the development of quantitative and scalable resource provisioning models for such environments. His work tends to connect the theoretical with the practical, architecting new networking systems that contribute to the development of the wireless Internet. In his research on QoS (quality of service), he developed a new approach to delivering service differentiation based in wireless networks based on economic theory supporting the notion of incentive engineering in wireless packet networks. And, in the area of programmable networks, Andrew has designed, developed and implemented one of the first programmable mobile networking platforms (Mobiware) with an emphasis on service creation in wireless networks.
One of Andrew's current projects is Armstrong, which is focused on resilient transport and control mechanisms for sensor networks. This project is developing new technologies for wireless sensor and ad hoc networks. This project is developing a new congestion control framework for wireless sensor networks, a new reliable transport protocol for wireless sensor networks, and a new routing scheme for wireless ad hoc networks that is based on dynamic variable transmission range power control.
Andrew is perhaps best known for his work on Cellular IP, which provided an alternative approach to that found in mobile telecommunications (e.g., General Packet Radio Service) and in IP networking (Mobile IP). Cellular IP represents a new mobile host protocol that is optimized to provide access to a Mobile IP enabled Internet in support of fast-moving wireless hosts. Cellular IP incorporates a number of important cellular principles but remains firmly based on IP design principles allowing Cellular IP to scale from pico- to metropolitan-area installations.
Andrew received a prestigious NSF CAREER award in 1999, and his other research grants come from a wide variety of federal and corporate sources.
Andrew has extensively served our scientific community through conference program committees and journal editorial boards. Most recently he was program co-chair for ACM MobiHoc 2005.
The CMC is pleased to have Andrew on the team.
July 2, 2005
With the rise of Voice over wireless LAN (VoWLAN), any complete WiFi security solution must address denial of service attacks, such as kicking off other clients, consuming excessive bandwidth, or spoofing access points, to the detriment of legitimate clients. Even authorized clients may be able to sufficiently disrupt service quality to make the network ineffective for legitimate clients. Our approach provides a new foundation for wireless network security, able to dynamically measure, analyze and protect a WiFi network against existing and novel threats, including rogue clients and access points, with a focus on VoWLAN use cases. Our goal is to support thousands of APs and clients, quickly recognize most new attacks, and generate few false alarms.
funded by HSARPA
Post-Doctoral RESEARCH FELLOW POSITION in SOCIOLOGY
AVAILABLE
(PDF format)
ISTS/CMC postdoctoral fellowships available
Arnab Paul
Minkyong
KimVirtual, moving fences controlled from a laptop could one day
herd cattle to fresh fields for grazing, a Dartmouth roboticist
told the MobiSys 2004 conference in Boston, Massachusetts, on
Sunday. A farmer would control multiple herds from a single
server at home as if they were playing a video game, said Zack
Butler, of Dartmouth College in Hanover, New Hampshire.Although
static virtual fences already keep dogs inside yards in affluent
US neighbourhoods, no-one has attempted a moving virtual fence
before, nor attempted to apply the idea to large herds of
animals. "Basically we download the fences to the cows," says
Butler. "We say: 'Today stay here, tomorrow go somewhere else.
Butler and his colleagues have written software that transmits
the chosen GPS co-ordinates of a virtual fence to head-collars
worn by the cows in the field. The entire article can be found
here.
Dartmouth College recently won the 2004 EDUCAUSE Excellence in
Networking award based on our wireless network. A representative
of the college will be making a presentation about our wireless
network at the EDUCAUSE national conference (19-22 October,
reception 19 October, presentation on 21 October, Denver). The
awards committee was especially struck that in addition to having
a robust and pervasive wireless network for so long, we were also
making innovative use of it in teaching, and in research that
involved students and that inspired a variety of student projects
(tools, applications, services), research or otherwise.
Network World Fusion magazine has named Brad as 44th on the
list of most powerful and influential individuals in networking.
Brad's name appears on a list which includes many illustrious
CEOs and industry leaders such as Steve Ballmer, John Chambers,
Bill Gates and Michael Dell. The entire
list can be viewed here. Network World Fusion had also run
an article on the Dartmouth Network earlier in November.
Congratulations to Sean Smith and his PKI team for receiving a
$100,000 cash donation from Cisco Systems to launch the Greenpass
project in the Center for Mobile Computing and the PKI lab. This
is the largest corporate grant yet to the CMC.
The goal of the Greenpass project is to apply PKI technology to
the challenge of authenticating users of WiFi wireless networks,
and specifically make it to make it possible to allow users to
delegate limited network access to visitors. With Greenpass, we
would be able to close Dartmouth's WiFi networks from the
drive-by spam artists and yet easily grant full network access to
a visiting colleague. There is significant corporate interest in
finding a solution to the "guest access" problem that is secure,
easy to use, cross plastform, and based on widely adopted
standards.
WBUR (Boston NPR radio station) ran a 5-minute story on
Dartmouth VoIP on wireless.
TeleSym, Inc. announced that its SymPhone System software for
voice calling on wireless networks has been selected for
campus-wide use at Dartmouth College, Hanover, NH. The
announcement coincides with the opening of the college's
conference titled Unleashed: The Summit on Wireless and Mobile
Computing.
SymPhone adds cordless-phone capability to mobile computers.
Under the Dartmouth contract, TeleSym will be supporting
thousands of users on one of the world's largest wireless IP
telephony installations, expected to eventually serve a community
of 13,000 students, faculty and staff.
Dartmouth has been the scene of many 'firsts' in organizational
computing, as the first Ivy League institution to be fully wired,
then fully wireless. By year-end, it will also be the first
college to fully deploy voice-over-IP (VoIP) on its wireless
networks. When you call from computer to computer, the quality
can be indistinguishable from wired phones and noticeably better
than cell phones.
More information can be found at this
page.
The CMC joins with Intel and Cisco to present a workshop to help leaders understand and plan for wireless networking.
Brad
Noblet, Director of Computing Techinical ServiceS, is the seventh
and newest member to join the CMC team. Brad, a veteran computer
industry manager, will be Dartmouth's new director of computing
technical services, with responsibility for Dartmouth's
data,telephone and cable TV networks, central machine room
operations and software development. A 1982 graduate of Indiana
University at Bloomington in computer science, Brad was that
school's manager of data communications, with responsibility for
the institution's statewide data network. He then left for
private industry, working in product development for a number of
hardware manufacturers. At Ungerman-Bass,Brad served as director
of engineering and general manager overseeing development of the
world's first smart hub -- a device that allows computers to
share a single network connection.
As vice president of product development at Cayman Systems, Brad led efforts to move that firm away from its dependence on Apple products. He was soon promoted to president by the Cayman board in order to continue the move away from dependency on Apple. He joined Wellfleet, a predecessor of Bay Networks, in 1995 to manage its router products division -- delivering 40 percent of Bay's profit and $600 million in annual revenue. Since leaving Bay Networks in 1998, Brad has been involved in a number of start-up ventures. Brad has responsibility for the campus data, telephone and cable TV networks; the operations of the central computer facility in Berry Library; and the software development group.
Sean Smith, Assistant Professor of
Computer Science, is now one of six faculty associated with the
CMC. His work increasingly addresses the authorization and
authentication issues involved with wireless networks and mobile
computing.
Sean has been working in information security---attacks and defenses, for industry and government---for over a decade. In graduate school, he worked with the US Postal Inspection Service on postal meter fraud; as a post-doc and staff member at Los Alamos National Laboratory, he performed security reviews, designs, analyses, and briefings for a wide variety of public-sector clients; at IBM T.J. Watson Research Center, he designed the security architecture for (and helped code and test) the IBM 4758 secure coprocessor, and then led the formal modeling and verification work that earned it the world's first FIPS 140-1 Level 4 security validation. Dr. Smith has published numerous refereed papers; given numerous invited talks; and been granted nine patents. His security architecture is used in thousands of financial, e-commerce, and rights managements installations world-wide.
In July 2000, Sean left IBM for Dartmouth since he was convinced that the academic education and research environment is a better venue for changing the world. His current work, as PI of the Dartmouth PKI Lab, investigates how to build trustable systems in the real world.
Sean was educated at Princeton (B.A., Mathematics) and CMU
(M.S., Ph.D., Computer Science).
Intel became the latest partner
of the CMC, primarily through the research labs in Hillsboro,
Oregon.
Les
Vadasz, Executive Vice President of Intel Corporation, and
President of Intel Capital, spoke on campus on May 16, 2003.
Mr. Vadasz is the #3 employee at Intel. He was visiting
Dartmouth and Tuck to review the College's research and
development efforts in mobile computing. Intel Capital has been
one of the most active strategic technology investors worldwide
during the past several years.
Mr. Vadasz's visit was sponsored by: the Center for Mobile Computing, the Dartmouth Entrepreneurial Network, the Department of Computer Science, the Foster Center for Private Equity, the Tuck School of Business, and the Thayer School of Engineering.
April 14, 2003 - Imagine a student entering a research lab and immediately receiving information on his or her laptop about current projects or equipment and safety updates. Or think about a professor keeping tabs on a reference book that a group of students keeps misplacing. These personalized services, which change depending on their location, are now being developed and tested on Dartmouth's wireless campus.
Discovery Channel Canada broadcast a three-part story about the campus wireless network: one, two, three [be sure to click the image to see the video]
Sensor networks, tracking stolen wireless devices, and off-campus wireless repeaters...
Ayorkor Mills-Tettey and Prof. David Kotz won the best student
paper award at the 21st IEEE International Performance,
Computing, and Communications Conference for their paper entitled
"Mobile Voice Over IP (MVOIP): An Application-level Protocol for
Call Hand-off in Real Time Applications".
Kobby
helped to deploy all of the hardware and software necessary
to trace the activity of the wireless network over the fall
term, and then to write the software necessary to crunch the
data. He went on to complete a senior thesis in computational
biology, and Fall 2002 he begins a Ph.D program in
bioengineering at the University of Pennsylvania.
Chris was awarded High Honors for
his work in the Solar project, in which he developed a small
language and run-time system that can define "roles" in terms
of the changing context. A role is a set of users who should
be granted certain access rights associated with that role.
For example, one might define a role called "room213" whose
membership should be defined to be any user currently located
in room 213. Then services, such as the projector, the room
lights, and the sound system, might grant access only to
users in role "room213".
Kazuhiro Minami presented his thesis proposal this spring.
His research will focus on the security and privacy issues
related to our Solar system for context-aware mobile
computing. He will solve two problems: first, controlling
access to context information produced by sensors and other
information sources, which is critical to protect the privacy
of people who are being monitored. Second, using context
information to make decisions about access to other services
in the environment.
Abe was awarded High Honors for his
work in the Solar project, in which he studied the
fundamental performance of Solar's event-distribution
mechanism, and added an extensible framework to allow events
to be distributed in a variety of formats, particularly XML.
Abe has founded his own company to develop and market his
Java persistence software tools.
We
are pleased to have Versus Technology as a new Partner of the
CMC. Their technology forms the cornerstone of the sensor
information used our context-aware application research. Versus
Technology, Inc. develops and sells leading-edge technology used
for process improvement in the health care, security, government,
and corporate markets. VIS (Versus Information System), a
real-time locating system based on patented dual infrared and
radio frequency technology, can be used to locate people and
equipment, manage assets, and control access.
In Sudikoff Lab, the home of the Department of Computer Science, electricians just installed a building-wide location-tracking system provided by Versus Technologies. The system allows us to track the location of asset tags attached to equipment, or badges attached to people, as they move about the building. The tags periodically emit an infrared (IR) (pulse, which is detected by a ceiling-mounted sensor. The system has one sensor per office, and a few sensors in larger labs and classrooms, so we can tell in which room a person or device is located. The sensors are all wired to a central collection system, which we will integrate into our Solar system so that applications can receive events about the location of people or devices of interest.
As a back-up mechanism, the mobile badges also emit a periodic radio frequency (RF) pulse that can be detected by an RF sensor. In our building we need one IR sensor for each room, and a few RF sensors for the whole building. As a result, if the IR system is unable to detect a badge, perhaps because it is in a pocket or obscured by other objects, the system can at least know whether the badge is still in the building.
Although we are intrigued by the approach in some of the prototype systems produced by research groups, such as the Cricket group at MIT, we chose Versus largely because it was able to provide a working system on a building-size scale, today, at a reasonable cost. (A typical Versus installation covers an entire hospital, to track staff and large mobile equipment.) We look forward to evaluating the success of an IR/RF approach to location tracking, and to the potential for using location data in applications.
Applications of this sort are "context-aware" in the sense that they base their behavior on the context in which they execute. Context information includes the location of the user and of relevant devices, the computational capabilities of the users device(s) and the network, the presence of other people, the traffic or weather conditions, and so forth.
At Dartmouth, the Solar system project investigates these ideas.
Guanling
defended his thesis proposal in which he outlined his plans
to develop the Solar system, an infrastructure that will
provide context information to mobile context-aware
applications. His innovative approach uses a network of
"operator" objects to filter and transform data collected
from sensors and distribute it to subscribing applications.
He plans to complete his Ph.D. in 2003.
Here at the CMC we immediately took advantage of this new network to enable several undergraduate research projects. Pablo Stern and Kobby Essien tracked the activity of every access point on campus, to capture a detailed picture of how the wireless network is used, who uses it, what they do with the network, and how they roam around campus. We'll repeat the study in the summer and fall when the network is more complete and more wireless devices are in place.
Dartmouth deployed its wireless access points in the existing building subnets, so a mobile user will switch subnets when roaming from building to building. Senior Ayorkor Mills-Tettey developed an extension to the H.323 telephony protocol that allows a voice-over-IP conversation to continue even when the mobile computer changes its IP address several times during the conversation. Senior Ammar Khalid developed a secure directory service to allow callers to initiate calls with mobile users, knowing only their name.
With wireless networking, computing devices become much more mobile. The CMC's "Solar" project aims to provide mobile applications information about their current context, such as location, so that they can adapt to the changing situation of their user. Ph.D. candidate Guanling Chen is developing the Solar infrastructure, and Senior Arun Mathias developed the first Solar application, a location-aware reminder program called SmartReminder.
The course on Computer Networks was excited to be a part of the action this Spring. In addition to the regular material, they were treated to a weekly seminar series on wireless networks and mobile computing. As a result several of their final projects were developed on Palm computers, and several took good advantage of IP multicast.
These are just a few of the exciting things that happened here this spring. You can find further details about the above projects in CMC papers, described within.
Cisco's University Research Program has generously donated a set of Aironet 802.11 access points and PC cards for use in CMC research. We are excited by this opportunity and look forward to working with them. One of our first planned projects is to instrument the campus wireless network to gather information about how our population uses the network: what protocols do they use? what sorts of applications do they use? how often do they roam between base stations? between buildings? and so forth. Other projects involved voice-over IP, location-sensitive content, and context-aware applications.
MERL is the US research laboratory for Mitsubishi Electric. Their charter is to conduct problem-driven basic research in computers and their uses, exploring entirely new categories of possibility rather than merely making incremental improvements to what is now possible. We look forward to working with them on fundamental challenges in mobile computing.
Nuance is a leading developer of speech-recognition software. Indeed, their technology is used in GM's OnStar network. In many mobile applications we believe that speech will be a more effective interface than keyboard or pen input, particularly in environments where the hands are busy elsewhere, such as when driving a car! Nuance has generously donated a license to their software for use in our teaching and research.
Research Engineer Bob Gray has assembled a large cluster of 50 Linux laptops, each with a WaveLAN Gold card (11 Mbps 802.11 wireless ethernet) and a GPS device. The cluster lives on several shelves in our lab, for development and testing, but will be taken out around campus for experiments involving wireless routing algorithms, mobile-agent applications, and so forth.
Apple Computer recently donated 10 iBooks with Airport wireless cards, an iMac DV, and an Airport base station. They are also the newest partner in the CMC. We are excited by the potential projects for these laptops and look forward to a fruitful partnership with Apple!
Microsoft Research joined CMC recently, and also generously donated a dozen PocketPC and WindowsCE portables, several RangeLAN wireless devices, and books and software about Windows CE programming. We have been using the devices in several undergraduate projects.
Clayton Okino is an assistant professor at the Thayer School of Engineering. His primary research interest is the performance of communication systems and wireless networks. Some of his current work focuses on statistical multiplexing schemes and smart sensor networks.
Ph.D: Jon Howell, Brian Brewington
B.A.: Jay Artz, Debbie Chyi, Ned Holbrook, Flora Wan