A year ago, the Bitcoin Core project announced a new process for disclosing security vulnerabilities, noting: “The project has historically done a poor job at publicly disclosing security-critical bugs, whether externally reported or found by contributors. This has led to a

In the fourth episode of the Privacy Series, filmed at @btcplusplus in Riga earlier this year, I sit down with @fjahr to discuss Cross Input Signature Aggregation, where one signature can validate spending multiple inputs, and its implications on Bitcoin Privacy.

For example if people have been running Tor but don't see many knots nodes that might change things, but that would be unrelated to ASmap.

So the clearnet knots nodes don't look suspicious to me based on their ASNs alone and for the Tor nodes a deeper analysis (fingerprinting) would be needed to tell if they are sybils or not. Happy to look at more data tomorrow if people disagree with these findings.

Top 5 ASNs of knots clearnet nodes belong to AT&T, Verizon, Spectrum, Deutsche Telekom, Cox representing 15% together; Top 5 ASNs of all other nodes: Hetzner, OVH, Amazon, Digital Ocean, GCP representing 27% together (obviously this nothing new)

So, without knowing what the people are running who report seeing very little knots nodes, it might be that they are just not using Tor. Looking at the small number of non-Tor knots IPs (872) they seem to mostly be running in ISPs and not the typical cloud providers.

While I am very happy to see people running ASmap, so far I can't confirm the that it filters (pun intended) knots nodes. The following numbers are all based on a bitnodes snapshot from today that I ran some basic analysis on: Knots nodes are 86% Tor, all others are 62% Tor.

Excited to share "Provable Cryptography for Bitcoin: An Introduction" - a comprehensive workbook that teaches formal security definitions and proofs through hands-on exercises. Solutions included!

🔥 Our jedi Master General Kenobi is connecting through holo-comm to the @BerlinBitDevs happening today! Join in to hear some real talk about SLICE, decentralization, and what it means to build the first fully @StratumV2 Bitcoin mining pool.

A statement on Bitcoin Core development and transaction relay policy -

Bitcoin Core developer @fjahr discusses Cross-Input Signature Aggregation (CISA), a proposed Bitcoin upgrade that could lower the cost of privacy-protecting collaborative transactions, benefitting activists, nonprofits, and businesses. Read the report: https://t.co/AEh65KohQK

Running DahLIAS (and secp256k1lab) 😎 https://t.co/O2D8eyodt2

Announcing DahLIAS! 🎉 The first crypto protocol for full cross-input signature aggregation that allows reusing Bitcoin's curve secp256k1. ✅ 64B sigs ✅ Verify is ~2x faster than half-agg'd Schnorr sigs ✅ 2-round signing Kudos to the team: @real_or_random @yannickseurin! 👇

*Before* using Bitcoin Core, don’t forget these two steps after downloading: 1. Verify the downloaded files. 2. Run `test_bitcoin` or `test_bitcoin.exe` on *your* machine.

After years of contributing to Bitcoin nights and weekends, Sebastian Falbesoner (@theStack) has left his job to focus 100% of his time on Bitcoin open source development.

We are excited to announce that Eugene Siegel has joined Brink as an open source engineer working on fuzz testing and Bitcoin Core development!

Here is one simple thing you can do that would be very helpful to test the Bitcoin Core release candidate. At home, start bitcoind with the -natpmp option. Let it start and stop it. Check if it could successfully open a port on your router. You can check this by looking at the

Thanks a lot to @HRF for supporting my work and initiating this report. I hope it helps people understand the potential that a CISA softfork could bring to Bitcoin and why we are excited about it.

NEW: @fjahr's long-awaited research into Cross-Input Signature Aggregation This is an extremely detailed and well-written exploration of CISA as a potential next step in Bitcoin development CISA's incentive alignment between privacy and cost-savings is mind-blowing

Brink renews our financial support for all of our 8 Bitcoin Core engineers through 2025! Thank you to @fanquake @glozow @hhebasto @theStack @dergoegge @stphnvlstk @fjahr and @marcofleon for your amazing work on Bitcoin and we are proud to support you. 🙏