Decred (DCR) Upgrade Adds Privacy Feature

September 4, 2019 / by Crypto.IQ

Decred, the project focused on governance, has added privacy features to its cryptocurrency DCR.

Decred unveiled the privacy feature in a blog post, stating that developers have been working on it since 2017. According to the blog post, Decred has found a middle ground between two extremes – Bitcoin and other privacy coins – offering the “right amount of privacy.”

Project-lead Jaky Yocom-Piatt shared some details on the new implementation, stating that it’s more effective than other privacy coins like Monero (XMR) or Zcash (ZEC). Developers aimed for simplicity, building the implementation with a few hundred lines of code, unlike the tens of thousands for other privacy implementations.

Decred’s privacy implementation is based upon the CoinShuffle++ paper “P2P Mixing and Unlinkable Bitcoin Transactions” by Ruffing, Moreno-Sanchez, and Kate from August 2016, which was a follow-up to these same authors’ 2014 CoinShuffle paper. ChoinShuffle++ has been integrated into Decred such that it offers opt-in privacy on all transactions, including stakeholders buying tickets, along with non-staking coin holders.

According to Yocom-Piatt, Decred can take advantage of the transactions that take place during its staking process via ticket purchases, making it relatively easier to obfuscate the identity of the senders. Other privacy coins, on the other hand, have to do all the heavy lifting during the mixing process. While privacy-centered coins hide both the sender and the amount sent, Decred only hides the sender’s identity in this current iteration.

 “Decred’s approach to hiding transactions leverages its steady substantial volume of ticket transactions, which makes it easier and more effective to hide the sender’s identity within the shuffle of governance participation,” said Yocom-Piatt. “Decred’s initial implementation addresses who is sending money to whom, meaning that for the initial implementation, privacy will be similar with that of Monero pre-confidential transactions.”

By leveraging its ticketing system, Decred does not require any additional cryptographic algorithms like ring signatures or zero-knowledge proofs. Another hard requirement for privacy coins is whether the total amount of coins can be audited at any time, which according to Yocom-Piatt is the case for Decred.

Decred’s project lead encouraged the community to test out the DCR code, which is available on GitHub. After some additional testing, the code implementation will become part of the master branch and will be included in the 1.5.0 release, adding:

“While the work already completed is substantive, there is still much to do.”

Looking forward, Yocom-Piatt stated that Decred plans to build an implementation for hiding transaction amounts as well, with Confidential Transactions (bulletproofs) being the preferred method to integrate it.