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arXiv · 1408.3079

A Lightweight Approach for Improving the Lookup Performance in Kademlia-type Systems

Abstract

Discovery of nodes and content in large-scale distributed systems is generally based on Kademlia, today. Understanding Kademlia-type systems to improve their performance is essential for maintaining a high service quality for an increased number of participants, particularly when those systems are adopted by latency-sensitive applications. This paper contributes to the understanding of Kademlia by studying the impact of \emph{diversifying} neighbours' identifiers within each routing table bucket on the lookup performance. We propose a new, yet backward-compatible, neighbour selection scheme that attempts to maximize the aforementioned diversity. The scheme does not cause additional overhead except negligible computations for comparing the diversity of identifiers. We present a theoretical model for the actual impact of the new scheme on the lookup's hop count and validate it against simulations of three exemplary Kademlia-type systems. We also measure the performance gain enabled by a partial deployment for the scheme in the real KAD system. The results confirm the superiority of the systems that incorporate our scheme.

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BibTeXRIS

Hani Salah, Stefanie Roos, Thorsten Strufe. 2014-07-27. A Lightweight Approach for Improving the Lookup Performance in Kademlia-type Systems. https://arxiv.org/abs/1408.3079

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