Logo
ScienceStack
Table of Contents
Fetching ...
Sign In

A Fully Local Last-Generated Rule in a Blockchain

Akira Sakurai, Kazuyuki Shudo

TL;DR

This paper proposes a locally applicable last-generated rule based on a relative time reference that reduces the proportion of honest miners following the attacker during chain ties by more than 40% compared to existing local methods.

Abstract

An effective method for suppressing intentional forks in a blockchain is the last-generated rule, which selects the most recent chain as the main chain in the event of a chain tie. This rule helps invalidate blocks that are withheld by adversaries for a certain period. However, existing last-generated rules face an issue in that their applications to the system are not fully localized. In conservative cryptocurrency systems such as Bitcoin, it is desirable for methods to be applied in a fully local manner. In this paper, we propose a locally applicable last-generated rule. Our method is straightforward and is based on a relative time reference. By conservatively setting the upper bound for the clock skews $Δ_{O_i}$ to 200 s, our proposed method reduces the proportion $γ$ of honest miners following the attacker during chain ties by more than 40% compared to existing local methods.

A Fully Local Last-Generated Rule in a Blockchain

TL;DR

This paper proposes a locally applicable last-generated rule based on a relative time reference that reduces the proportion of honest miners following the attacker during chain ties by more than 40% compared to existing local methods.

Abstract

An effective method for suppressing intentional forks in a blockchain is the last-generated rule, which selects the most recent chain as the main chain in the event of a chain tie. This rule helps invalidate blocks that are withheld by adversaries for a certain period. However, existing last-generated rules face an issue in that their applications to the system are not fully localized. In conservative cryptocurrency systems such as Bitcoin, it is desirable for methods to be applied in a fully local manner. In this paper, we propose a locally applicable last-generated rule. Our method is straightforward and is based on a relative time reference. By conservatively setting the upper bound for the clock skews to 200 s, our proposed method reduces the proportion of honest miners following the attacker during chain ties by more than 40% compared to existing local methods.

Paper Structure

This paper contains 11 sections, 2 theorems, 6 equations, 2 figures, 1 algorithm.

Table of Contents

  1. Introduction
  2. Related Work
  3. Proposed Method
  4. Model
  5. Details
  6. Evaluation
  7. Theoretical Analysis
  8. Simulation Experiments
  9. Simulation Settings
  10. Simulation Result
  11. Conclusion

Key Result

Theorem 1

Let $t_B$ denote the timestamp of a block, and let $a_l$ represent the reception time of that block. If the following condition holds, then the creator of the block is an adversary:

Figures (2)

  • Figure 1: Simulation results for $\gamma$ when $\Delta_{O_i} = 20$ s.
  • Figure 2: Simulation results for $\gamma$ when $\Delta_{O_i} = 200$ s.

Theorems & Definitions (4)

  • Theorem 1
  • proof
  • Theorem 2
  • proof