  Digital equity in Internet access is often measured along three axes:
availability, affordability, and adoption. Most prior work focuses on
availability; the other two aspects have received little attention. In this
paper, we study broadband affordability in the US. Specifically, we focus on
the nature of broadband plans offered by major ISPs across the US. To this end,
we develop a broadband plan querying tool (BQT) that obtains broadband plans
(upload/download speed and price) offered by seven major ISPs for any street
address in the US. We then use this tool to curate a dataset, querying
broadband plans for over 837k street addresses in thirty cities for seven major
wireline broadband ISPs. We use a plan's carriage value, the Mbps of a user's
traffic that an ISP carries for one dollar, to compare plans. Our analysis
provides us with the following new insights: (1) ISP plans vary inter-city.
Specifically, the fraction of census block groups that receive high and low
carriage value plans varies widely by city; (2) ISP plans intra-city are
spatially clustered, and the carriage value can vary as much as 600% within a
city; (3) Cable-based ISPs offer up to 30% more carriage value to users when
competing with fiber-based ISPs in a block group; and (4) Average income in a
block group plays a critical role in dictating who gets a fiber deployment
(i.e., a better carriage value) in the US. While we hope our tool, dataset, and
analysis in their current form are helpful for policymakers at different levels
(city, county, state), they are only a small step toward understanding digital
equity. Based on our learnings, we conclude with recommendations to continue to
advance our understanding of broadband affordability.
