Analytical study of consistency and performance of DHTs under churn
(English)Manuscript (preprint) (Other academic)
In this paper, we present a complete analytical study of dynamic membership (aka churn) in structured peer-to-peer networks. We use a master-equation-based approach, which is used traditionally in non-equilibrium statistical mechanics to describe steady-state or transient phenomena. We demonstrate that this methodology is infact also well suited to describing structured overlay networks by an application to the Chord system. For any rate of churn and stabilization rates, and any system size, we accurately account for the functional form of: the distribution of inter-node distances, the probability of network disconnection, the fraction of failed or incorrect successor and finger pointers and show how we can use these quantities to predict both the performance and consistency of lookups under churn. Additionally, we also discuss how churn may actually be of different ’types’ and the implications this will have for structured overlays in general. All theoretical predictions match simulation results to a high extent. The analysis includes details that are applicable to a generic structured overlay deploying a ring as well as Chord-specific details that can act as guidelines for analyzing other systems.
Peer-To-Peer, Structured Overlays, Distributed Hash Tables, Dynamic Membership in Large- scale Distributed Systems, Analytical Modeling, Master Equations
IdentifiersURN: urn:nbn:se:kth:diva-25104OAI: oai:DiVA.org:kth-25104DiVA: diva2:355831
QC 20101008. The work was reported in the following two publications: Sameh El-Ansary, Supriya Krishnamurthy, Erik Aurell and Seif Haridi, An Analytical Study of Consistentcy and Performance of DHTs under Churn. Technical Report TR-2004-12, SICS, October 2004.
Supriya Krishnamurthy, Sameh El-Ansary, Erik Aurell and Seif Haridi, A Statistical Theory of Chord under Churn. In the 4th Annual InternationalWorkshop on Peer-To-Peer Systems (IPTPS 05), Ithaca, NY, USA, February 2005