Things I need to read:
P2P MetaData Search Layers

The abstract:
"Distributed Hashtables (DHTs) provide a scalable method of
associating file-hashes with a particular location in a distributed network
environment. Modifying DHTs directly to support meta-data is difficult, and
meta-data search systems such as flooding tend to scale poorly. However, a
number of more scalable distributed meta-data search systems have recently
been developed that could be deployed in tandem with DHTs, and several are
discussed here along with some novel simulation results that concern the
scalability and resource limitations of a meta-data search layer that employs
semantic routing. Semantic routing is a method of pruning a flooding search
such that queries are preferentially forwarded to nodes that can answer those