A survey on self‐organized semantic storage <s> Edutella <s> Metadata for the World Wide Web is important, but metadata for Peer-to-Peer (P2P) networks is absolutely crucial. In this paper we discuss the open source project Edutella which builds upon metadata standards defined for the WWW and aims to provide an RDF-based metadata infrastructure for P2P applications, building on the recently announced JXTA Framework. We describe the goals and main services this infrastructure will provide and the architecture to connect Edutella Peers based on exchange of RDF metadata. As the query service is one of the core services of Edutella, upon which other services are built, we specify in detail the Edutella Common Data Model (ECDM) as basis for the Edutella query exchange language (RDF-QEL-i) and format implementing distributed queries over the Edutella network. Finally, we shortly discuss registration and mediation services, and introduce the prototype and application scenario for our current Edutella aware peers. <s> BIB001 </s> A survey on self‐organized semantic storage <s> Edutella <s> We present Tapestry, a peer-to-peer overlay routing infrastructure offering efficient, scalable, location-independent routing of messages directly to nearby copies of an object or service using only localized resources. Tapestry supports a generic decentralized object location and routing applications programming interface using a self-repairing, soft-state-based routing layer. The paper presents the Tapestry architecture, algorithms, and implementation. It explores the behavior of a Tapestry deployment on PlanetLab, a global testbed of approximately 100 machines. Experimental results show that Tapestry exhibits stable behavior and performance as an overlay, despite the instability of the underlying network layers. Several widely distributed applications have been implemented on Tapestry, illustrating its utility as a deployment infrastructure. <s> BIB002
The Edutella system proposes an RDF-based P2P network infrastructure designed from a use case for improved networking between educational institutions BIB001 . Even though the name suggests a conceptual relationship to the unstructured Gnutella protocol, Edutella uses the JXTA framework developed by Sun Microsystems as its networking layer. JXTA in turn is based on the Tapestry concept of a distributed hash table (DHT) in the particular form of a prefix tree (trie)  ). Tapestry provides de-centralized object location using a hash function to map stored objects and participating nodes to an opaque identifier BIB002 . Each node is responsible for resolving a certain hash prefix based on its node identifier. In order to route requests, each node also keeps a list of neighboring nodes and their prefixes.