Query Processing in Super-Peer Networks with Languages Based on Information Retrieval: The P2P-DIET Approach

Abstract

Abstract. This paper presents P2P-DIET, an implemented resource sharing system that unifies one-time and continuous query processing in super-peer networks. P2P-DIET offers a simple data model for the description of network resources based on attributes with values of type text and a query language based on concepts from Information Retrieval. The focus of this paper is on the main modelling concepts of P2P-DIET (metadata, advertisements and queries), the routing algorithms (inspired by the publish/subscibe system SIENA) and the scalable indexing of resource metadata and queries.

Self-organising Applications Using Lightweight Agents

“…The DIET platform has also been used to implement the extensible P2P service P2P-DIET [19,20,22,34]. P2P-DIET is a super-peer system and has two kinds of nodes: super-peers and clients (see Fig.…”

P2p-Diet

“…In addition, the following data structures are exploited at each super-peer: (i) a resource index (an inverted file) for answering queries about local resources, (ii) a query index that is used by al-gorithm BestFitTrie [6] to find efficiently which continuous queries are matched by an incoming notification, and (iii) a poset that keeps track of subsumption relations among the continuous queries posted to a super-peer by its clients or forwarded by other super-peers (as in SIENA [1]). …”

Designing Semantic Publish/Subscribe Networks Using Super-Peers

“…For example, the super-peers may form an unstructured overlay like in P2P-DIET [21]. P2P-DIET does not force any kind of structure between super-peers.…”

“…We use two kinds of indices, namely the super-peer/super-peer indices (SP/SP indices) that handle communication in the super-peer backbone and the super-peer/peer indices (SP/P indices) that handle communication between a super-peer and all peers connected to it. These indices draw upon our previous work for query routing, as discussed in [29], as well as further extensions and modifications necessary for publish/subscribe services based on [24,21]. Except for the functionality they employ, both indices use the same data structures, have the same update process, etc.…”

“…SIENA servers additionally utilize partially ordered sets encoding subscription and advertisement subsumption to minimize network traffic. The core ideas of SIENA have recently been used in the pub/sub systems DIAS [23] and P2P-DIET [2,24,21] but now the data models utilized were inspired from Information Retrieval. DIAS and P2P-DIET have also emphasized the use of sophisticated subscription indexing at each server to facilitate efficient forwarding of notifications [42].…”