Summary: Profiling a Million User DHT
Jarret Falkner Michael Piatek John P. John Arvind Krishnamurthy Thomas Anderson
University of Washington
Distributed hash tables (DHTs) provide scalable, key-based
lookup of objects in dynamic network environments. Al-
though DHTs have been studied extensively from an an-
alytical perspective, only recently have wide deployments
enabled empirical examination. This paper reports mea-
surements of the Azureus BitTorrent client's DHT, which is
in active use by more than 1 million nodes on a daily basis.
The Azureus DHT operates on untrusted, unreliable end-
hosts, offering a glimpse into the implementation challenges
associated with making structured overlays work in practice.
Our measurements provide characterizations of churn, over-
head, and performance in this environment. We leverage
these measurements to drive the design of a modified DHT
lookup algorithm that reduces median DHT lookup time by
an order of magnitude for a nominal increase in overhead.
Categories and Subject Descriptors