  Distributed securities exchanges may become de facto fragmented if they span
geographical regions with asymmetric computer infrastructure. First, we build
an economic model of a decentralized exchange with two miner clusters, standing
in for compact areas of economic activity (e.g., cities). "Local" miners in the
area with relatively higher trading activity only join a decentralized exchange
if they enjoy a large speed advantage over "long-distance" competitors. This is
due to a transfer of economic value across miners, specifically from high- to
low-activity clusters. Second, we estimate the speed advantage of "local" over
"long-distance" miners in a series of Monte Carlo experiments over a
two-cluster, unstructured peer-to-peer network simulated in C. We find that the
speed advantage increases in the level of infrastructure asymmetry between
clusters. Cross-region DEX blockchains are feasible as long as the asymmetry
levels in trading activity and infrastructure availability across regions are
positively correlated.
