--- 1/draft-ietf-p2psip-self-tuning-13.txt 2014-06-16 12:14:29.779603837 -0700 +++ 2/draft-ietf-p2psip-self-tuning-14.txt 2014-06-16 12:14:29.827604995 -0700 @@ -1,19 +1,19 @@ P2PSIP Working Group J. Maenpaa Internet-Draft G. Camarillo Intended status: Standards Track Ericsson -Expires: December 16, 2014 June 14, 2014 +Expires: December 18, 2014 June 16, 2014 Self-tuning Distributed Hash Table (DHT) for REsource LOcation And Discovery (RELOAD) - draft-ietf-p2psip-self-tuning-13.txt + draft-ietf-p2psip-self-tuning-14.txt Abstract REsource LOcation And Discovery (RELOAD) is a peer-to-peer (P2P) signaling protocol that provides an overlay network service. Peers in a RELOAD overlay network collectively run an overlay algorithm to organize the overlay, and to store and retrieve data. This document describes how the default topology plugin of RELOAD can be extended to support self-tuning, that is, to adapt to changing operating conditions such as churn and network size. @@ -26,21 +26,21 @@ Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at http://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." - This Internet-Draft will expire on December 16, 2014. + This Internet-Draft will expire on December 18, 2014. Copyright Notice Copyright (c) 2014 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents @@ -50,28 +50,28 @@ the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 3. Introduction to Stabilization in DHTs . . . . . . . . . . . . 5 3.1. Reactive vs. Periodic Stabilization . . . . . . . . . . . 5 3.2. Configuring Periodic Stabilization . . . . . . . . . . . 6 - 3.3. Adaptive Stabilization . . . . . . . . . . . . . . . . . 7 + 3.3. Adaptive Stabilization . . . . . . . . . . . . . . . . . 8 4. Introduction to Chord . . . . . . . . . . . . . . . . . . . . 8 5. Extending Chord-reload to Support Self-tuning . . . . . . . . 9 5.1. Update Requests . . . . . . . . . . . . . . . . . . . . . 10 - 5.2. Neighbor Stabilization . . . . . . . . . . . . . . . . . 10 + 5.2. Neighbor Stabilization . . . . . . . . . . . . . . . . . 11 5.3. Finger Stabilization . . . . . . . . . . . . . . . . . . 11 5.4. Adjusting Finger Table Size . . . . . . . . . . . . . . . 11 - 5.5. Detecting Partitioning . . . . . . . . . . . . . . . . . 11 + 5.5. Detecting Partitioning . . . . . . . . . . . . . . . . . 12 5.6. Leaving the Overlay . . . . . . . . . . . . . . . . . . . 12 6. Self-tuning Chord Parameters . . . . . . . . . . . . . . . . 12 6.1. Estimating Overlay Size . . . . . . . . . . . . . . . . . 12 6.2. Determining Routing Table Size . . . . . . . . . . . . . 13 6.3. Estimating Failure Rate . . . . . . . . . . . . . . . . . 13 6.3.1. Detecting Failures . . . . . . . . . . . . . . . . . 14 6.4. Estimating Join Rate . . . . . . . . . . . . . . . . . . 15 6.5. Estimate Sharing . . . . . . . . . . . . . . . . . . . . 15 6.6. Calculating the Stabilization Interval . . . . . . . . . 17 7. Overlay Configuration Document Extension . . . . . . . . . . 18 @@ -102,25 +102,29 @@ routine to counter the undesirable effects of churn on routing. To configure the parameters of a DHT, some characteristics such as churn rate and network size need to be known in advance. These characteristics are then used to configure the DHT in a static fashion by using fixed values for parameters such as the size of the successor set, size of the routing table, and rate of maintenance messages. The problem with this approach is that it is not possible to achieve a low failure rate and a low communication overhead by using fixed parameters. Instead, a better approach is to allow the system to take into account the evolution of network conditions and - adapt to them. This document extends the mandatory-to-implement - chord-reload algorithm by making it self-tuning. Two main advantages - of self-tuning are that users no longer need to tune every DHT - parameter correctly for a given operating environment and that the - system adapts to changing operating conditions. + adapt to them. + + This document extends the mandatory-to-implement chord-reload + algorithm by making it self-tuning. The use of the self-tuning + feature is optional. However, when used, it needs to be supported by + all peers in the RELOAD overlay network. Two main advantages of + self-tuning are that users no longer need to tune every DHT parameter + correctly for a given operating environment and that the system + adapts to changing operating conditions. The remainder of this document is structured as follows: Section 2 provides definitions of terms used in this document. Section 3 discusses alternative approaches to stabilization operations in DHTs, including reactive stabilization, periodic stabilization, and adaptive stabilization. Section 4 gives an introduction to the Chord DHT algorithm. Section 5 describes how this document extends the stabilization routine of the chord-reload algorithm. Section 6 describes how the stabilization rate and routing table size are calculated in an adaptive fashion.