Bitcoin Developers Publish BIP For 'Dandelion' Privacy Project

Researchers looking to beef up bitcoin’s privacy features have released a new proposal on GitHub.

AccessTimeIconJun 13, 2017 at 5:35 p.m. UTC
Updated Sep 11, 2021 at 1:26 p.m. UTC

Researchers looking to beef up bitcoin’s privacy features have released a new proposal on GitHub.

Dubbed ‘Dandelion’, the project has been pitched as a privacy-enhancing modification to bitcoin's transaction propagation mechanism. First launched in January this year, Dandelion is currently running on the bitcoin testnet for trial and feedback. More information can be found in the official Bitcoin Improvement Proposal here.

According to an email on the bitcoin development mailing list written by Zcash advisor and University of Illinois assistant professor Andrew Miller, the project is aimed at obscuring the original source IP of each bitcoin transaction by breaking the transaction proceeds into two phases: "stem" and "fluff".

As Miller explained:

"During the stem phase, each node relays the transaction to a single peer. After a random number of hops along the stem, the transaction enters the fluff phase, which behaves just like ordinary transaction flooding/diffusion. Even when an attacker can identify the location of the fluff phase, it is much more difficult to identify the source of the stem."

According to the letter, Dandelion's backers also include a faculty member from University of Illinois, Pramod Viswanath; two graduate students, Surya Bakshi, Shaileshh Bojja Venkatakrishnan; and one post-doctoral student, Giulia Fanti.

The work has taken place amidst the wider backdrop of development around privacy improvements, a goal to which projects such as MimbleWimble have advanced in recent months.

Image via Shutterstock

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