In just two days, on Wednesday, April 7th, a select group of Bitcoin Core developers will showcase a demonstration featuring “attack blocks” that are designed to significantly prolong verification times on the Signet network.
The event is scheduled for 10 AM EST (2 PM UTC). Anyone interested in joining can operate a Bitcoin Core node on Signet and observe the mining and processing of these blocks in real-time through their own node.
For those looking to participate, detailed instructions are available to help set up a node and track the verification times for these attack blocks via your node’s logs.
This demonstration will not reveal the most extreme scenario of the attack (the specific script and transaction structure have been kept confidential to prevent providing additional insights to potential malicious actors), but it will generate blocks that require significantly more time for verification compared to standard blocks.
The primary goal of this demonstration is to highlight one of four critical consensus vulnerabilities that the Great Consensus Cleanup initiative seeks to address with BIP 54.
Additionally, two more demonstrations are planned: one at 6 PM EST (10 PM UTC) on April 8th, and another at 5 AM EST (9 AM UTC) on April 9th. This scheduling aims to accommodate Bitcoin users across various global time zones so they can engage directly as well.
The current size of the Signet blockchain is approximately 32-33 GB. Therefore, if you possess any device with sufficient storage capacity, feel free to set up a Signet node and take part in this event.
Please note that this software patch was quickly assembled for this demonstration without thorough auditing (although it functions as a basic terminal-based GUI). If you’re launching an entirely new Signet node specifically for this demo on an unfunded machine, you should be safe even if you tend toward paranoia like I do.
If you’d prefer not just sifting through log files manually, AJ Towns has contributed a patch for the “bitcoin-tui” project—a terminal-based GUI designed for Bitcoin Core—to visualize attack blocks during the demonstration. The creator of this project is working towards an official release before the event; however, compiling it yourself is also an option.
You can execute these commands in Linux (git commands should work across other operating systems too; equivalent CLI commands can easily be found online):
git clone https://github.com/ajtowns/bitcoin-tui.git cd bitcoin-tui git switch 202604-bip54blocks
Afterward, simply follow the build instructions provided in their repository. Once compiled successfully, ensure your bitcoind configuration file includes “server=1,” then launch bitcoin-tui. You should see a “Slow Blocks” tab located at the top right corner of your interface.
This article titled “Demonstration of ‘Attack Blocks’ On Bitcoin’s Signet Test Network” was originally published by Shinobi in Bitcoin Magazine.