PhD Defense: Morgan Vigil-Hayes, "Community-Based Networks for Challenged Environments"

Wednesday, June 14, 2017 - 10:00am
1132 Harold Frank Hall
Community-Based Networks for Challenged Environments
Morgan Vigil-Hayes
Elizabeth Belding (Chair), Amr El Abbadi, Ben Zhao, and Ellen Zegura


The Internet as a networked system has been rendered more complex than ever before as human endpoints are grafted into the system via increasingly pervasive and personalized networked devices. According to the United Nations, the Internet is a transnational enabler of a number of human rights, and as such, access to the Internet has been proclaimed to be a basic right unto itself. Unfortunately, even as networked devices have become ubiquitous, access to the Internet has not. In many cases, the reasons behind this digital divide involve contextual challenges such as limited infrastructure, limited economic viability, and rugged terrain. In this dissertation, we seek to ameliorate these challenges by designing data-driven, community-based network infrastructure. 

In order to extend Internet connectivity to communities located in some of the most challenging contexts, we start by understanding how Internet connectivity is used when communities receive initial Internet access. We do this by partnering with two ISPs (Internet service providers) that brought initial Internet connectivity to two geographic regions in Indian Country. The data we have collected from these two ISPs totals to 115 TB generated over a combined three years of partnerships. Our ISP collaborators serve a total of 1,300 subscribers who represent residents of 14 different Native American reservations representing 18 different tribes. The service areas of these ISPs include predominantly rural communities located on mountainous and forested terrain. Key findings from our analysis of data generated by these ISPs include: the prevalence of social media and streaming content, the locality of interest with respect to social media content, and the similarity of Web browsing preferences between households and the aggregate communities to which they belong. Based on the results our analyses as well as findings in related work, we design four community-based network technologies that address the network challenges associated with rural and developing contexts.

First, we introduce a social media content distribution system that operates over FM radio. In order to provide content over a 1.2 Kbps technology (the Radio Broadcast Data System), we create a graph-based metric, the cumulative clustering coe cient, to filter content based on its total audience size and the diversity of its audience scope. Next, we introduce FiDO, a community-based Web browsing agent and content delivery system that enables users from disconnected households to collect relevant content for themselves and members of their households opportunistically from content caches co-located with cellular base stations.

We then describe some of the challenges associated with content creation and data collection in rural and developing contexts and introduce Open Development Kit (ODK) Submit and VillageShare for rural schools. ODK Submit is a smartphone-based platform that seeks to ease the burden of navigating heterogeneous network conditions for application developers, data collectors, and data processors. VillageShare enables schools in poorly-connected, rural areas to create and share culturally relevant curricula and empowers students to work collaboratively on “local cloud-based” projects despite their lack of access to network connectivity at home.

We conclude with an overview of our key findings as well as a discussion of future research directions inspired by the work in this dissertation. 

Everyone welcome!