Bitcoin Core suggested improved Confidential Transactions

According to Gregory Maxwell, Bitcoin Core developer, using the Confidential Transactions, the size of a typical bitcoin transaction can be reduced by 20 times
15 November 2017   1340

The Confidential Transactions  technology received a new development impulse.

The technology, which was first announced in 2015 by Dr. Adam Beck, uses the so-called "Pederson's obligations" and assumes that it is possible to make the transferable amount visible only to the direct participants of the transaction or the third party assigned to them.

However, such transactions are not in themselves a universal solution, since they hide only the amount of the transfer, and not the address of the sender and the recipient.

A new approach to the issue was suggested by Bitcoin Core developer Gregory Maxwell. His model involves using the CoinJoin method to combine transaction outputs into one large transaction, which will hide the links between users from outside observers.

As Maxwell says, in this case the amount of payment will be available only to the "sender, recipient and those to whom they will provide special keys for viewing information."

In addition to increased privacy, the proposed method solves another important task related to the issue of scaling. In particular, it allows you to significantly optimize the weight of transaction confirmation.

It is necessary to understand that the technology of Confidential Transactions, in the background of all its advantages, is rather resource-intensive. It is this problem that Maxwell decided, optimizing a number of indicators.

The primary advantage of this approach is that it can be constructed without any substantial new cryptographic assumptions (e.g., only discrete log security in our existing curve), that it can be high performance compared to alternatives, that it has no trusted setup, and that it doesn't involve the creation of any forever-growing unprunable accumulators. All major alternative schemes fail multiple of these criteria (e.g., arguably Zcash's scheme fails every one of them).

Gregory Maxwell
Developer, Bitcoin Core

Charlie Lee, creator of Litecoin, found this technology very interesting.

According to Maxwell, the size of a typical bitcoin transaction using the advanced technology of Confidential Transactions can be reduced by about 20 times.

1st Alternative Zcash Client to be Created by Parity

The responsibility for the continued development and support of the new client called Zebra will be with the Zcash Foundation
18 June 2019   126

The leading developer of solutions for the Ethereum ecosystem, Parity Technologies, presented the first alternative client for cryptocurrency Zcash.

A new client called Zebra is designed to improve the security of the Zcash network. So, if the original Zcashd client will not be able to operate for some reason, the blockchain will be supported by nodes on Zebra.

In addition, with the help of an alternative client, developers will be able to identify bugs and eliminate defects in consensus.

The community wins across the board, as there are now more core developers working on clients, with more interests represented and clients taking different approaches on how to build apps on top. Zcash can now boast a more diversified community that can effectively tailor experiences for Layer 2 developers as well as end-users.

Fredrik Harryson
CTO, Parity Technologies

The responsibility for the continued development and support of the Zebra will be with the Zcash Foundation.