Skip Tree Graph: a Distributed and Balanced Search Tree for Peer-to-Peer Networks

Abstract

Skip Tree Graph is a novel, distributed, data structure for peer-to-peer systems that supports exact-match and order-based queries such as range queries efficiently. It is based on skip trees, which are randomised balanced search trees equivalent to skip lists and designed to provide improved concurrency. Skip tree graphs constitute an extension of skip graphs enhancing their performance in both, exact-match and range queries. Moreover, skip tree graph maintains the underlying balanced tree structures using randomisation and local operations, which provides a greater degree of concurrency and scalability.

An Efficient Routing Method for Range Queries in Skip Graph

“…Note that another method called Tree-based in [9] is out of the scope of this paper. This is because it uses additional links, being particular to Skip Tree Graph [13] and requiring a commensurate maintenance cost; we are focusing on handling range queries in a normal topology of Skip Graph for versatility. The sequential traversing method can deliver a range query to all corresponding nodes with the minimum number of messages, without any duplicate transmission.…”

Fault tolerance on improved distributed spanning tree structure

“…Another branch of the skip list is the skip tree, based on which the skip tree graph [7] was proposed and it provides similar performance with rainbow skip graph. Besides, O. Angel, et al [3] discussed the complexity of routing in faulty network, both for hypercube and n-dimensional mesh.…”

“…Peers can selforganize networks that are overlaid the existing network to provide symmetric communication and distributed control. Several data structures, such as hash tables, tries, binary search tree, 2-3 trees, AVL trees, skip list and B-trees, were used to organize peers and manage the resources [7]. As the unreliable peers and connections, the original data structures are not reliable.…”

“…string prefix searching, range queries. In order to resolve this problem, other structures such as skip graph [1], SkipNet [12] and skip tree graph [7] are presented. They are based on the skip list and provide similar performance to the DHT.…”

Multi-level reconfigurable self-organization in overlay services

“…Based on this concept, overlay networks can be organized in various complex indexing structures such as skip graphs [Aspnes and Shah, 2007] or skip tree graphs [Beltran et al, 2007] providing flexibility and e ciency in applications of distributed databases and storage management systems. Nevertheless, an overlay network based on skip lists requires a complex building and maintenance in a distributed context.…”