  The distribution of files using decentralized, peer-to-peer (P2P) systems,
has significant advantages over centralized approaches. It is however more
difficult to settle on the best approach for file sharing. Most file sharing
systems are based on query string searches, leading to a relatively simple but
inefficient broadcast or to an efficient but relatively complicated index in a
structured environment. In this paper we use a browsable peer-to-peer file
index consisting of files which serve as directory nodes, interconnecting to
form a directory network. We implemented the system based on BitTorrent and
Kademlia. The directory network inherits all of the advantages of
decentralization and provides browsable, efficient searching. To avoid conflict
between users in the P2P system while also imposing no additional restrictions,
we allow multiple versions of each directory node to simultaneously exist --
using popularity as the basis for default browsing behavior. Users can freely
add files and directory nodes to the network. We show, using a simulation of
user behavior and file quality, that the popularity based system consistently
leads users to a high quality directory network; above the average quality of
user updates. Q
