and semanticbased service discovery on the Grid. We argue that these two models can benefit from each other in the sense that SONs can be constructed by exploiting DHTs mechanisms thus enlightening the way to the semantics-free content publishing and retrieval mechanisms of the latter. In particular, ERGOT allows

and SONs to enable semantic-based service discovery in distributed infrastructures such as Grids and Clouds. ERGOT uses semantic annotations that enrich service specifications in two ways: (i) services are advertised in the DHT on the basis of their annotations, thus allow-ing us to establish a SON between

the inherent scalability and fault-tolerance of DHTs. The Scalaris key/value store supports strong data con-sistency and atomic transactions. It uses an enhanced Paxos Commit protocol with only four communication steps rather than six. This improvement was possible by exploiting information from the replica

-scale grids. In particular, we propose a distributed semantics-based discovery framework. We show how this framework can be used to address the discovery problem in such grids and improve three aspects of performance: expressiveness, scalability, and efficiency.

Distributed Hash Tables (DHTs) are scalable, self-organizing, and adaptive to underlying topology changes, thus being a promising infrastructure for hosting large-scale distributed applications. The ever-wider use of DHT infrastructures has found more and more applications that require support

to organize large amounts of information and make computa-tions. What they can not do is to “understand ” the information and hence, can not easily aid us in our reasoning tasks. The Semantic Web (SW) is an effort towards enabling computers to better interpret the information. The SW is based on having both

content based on term overlap and systems that map both the content and queries on a shared semantic data structure. In this paper we present the pNear system that combines DHTs with clustering via term overlap and show that we are able to tackle some important disadvantages that hold for the individual

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To address privacy concerns over Online Social Networks (OSNs), we propose a distributed, peer-to-peer approach coupled with encryption. Extending the distributed approach by direct data exchange between user devices removes the strict connectivity requirements of web-based OSNs. In order to verify