Jay Chen - Projects

Jay Chen - Projects - Publications
RuralCafe RuralCafe is a platform for web search and browsing over extremely slow or intermittent networks or when no connection is available at all. RuralCafe has a variety of deployment configurations depending on the physical resources and permissions available.	Contextual Information Portal Generator A Contextual Information Portal is an offline repository of web pages tailored to the particular context in which it is to be used. A CIP is intended to be paired with some server software (e.g. RuralCafe) and a user interface (e.g. a web browser) so that users can reliably interact with large amounts of context appropriate web content while being completely offline or behind a slow/intermittent connection.
SMS Find SMS Find is a SMS-based search service that gives users immediate access to information on their mobile phone without subscription to a data plan. SMS Find is targeted at people who for whatever reason do not have access to a WAP enabled phone or a data plan.	Event Logger for Firefox (ELF) Event Logger for Firefox (ELF) is a Firefox extension that logs various browsing statistics and reports them back to a central server for analysis. It is an easily deployable client-side logging tool for researchers to understand search and browsing behavior.
TCP Behavior in Sub-Packet Regimes Many network links in developing regions operate in the subpacket regime, an environment where the typical per-flow throughput is less than 1 packet per round-trip time. TCP and other common congestion control protocols break down in the sub-packet regime, resulting in severe unfairness, high packet loss rates, and flow silences due to repetitive timeouts. To understand TCP's behavior in this regime, we propose a model particularly tailored to high packet loss-rates and relatively small congestion window sizes. Learn more: SIGMETRICS 2011 Poster (pdf) Note: The bulk of this work has not yet been published. We implemented a prototype to address the issues we identified and validate the model under a variety of network conditions. Please email me directly if you have specific questions.	Epothecary An anti-counterfeiting track and trace system which uses built-in functionality in midlevel mobile telephones including cameras, SMS, and optionally GPS to construct a robust system for tracking and verifying the pedigrees of pharmaceutical products at every point in the distribution chain. Pilot deployment coming soon. Learn more: Mobiheld 2009 Paper (pdf)
UjU A mobile application platform that simplies the design of new SMS-based mobile applications. We have successful deployments with clients in Ghana, Mexico, and India. Learn more: DEV 2010 Paper (pdf) Note: I am the chief architect of this work, we have since spun this out into a small startup. Please contact me directly if you are interested in using our solution for extremely low-cost data collection. I would also be happy to discuss whether UjU is the appropriate technology for your projects.	Data Transmission over Unknown Voice Channels (Hermes) A physical layer modulation/demodulation protocol that enables data communication over unknown acoustic voice channels. Hermes provides 1.5 Kbps data connectivity over a narrowband 3 Khz GSM voice channel. Learn more: MobiCom 2010 Paper (pdf)