Borromean Ring Signature and Privacy-Aware Transactions

In two days’ time, Bitcoin will be 15 years old. Overall, Satoshi imagined a peer-to-peer trading system which could not be stopped or compromised in any way. This new world would not involve intermediaries to determine if Bob could trade with Alice but involved miners checking every transaction. Rather than bank account details and IBAN strings, this new digital currency would use elliptic curve signing methods (ECDSA) and allow anyone to create a digital wallet without the interference of corporations. It would allow those without bank accounts to trade without any interference.

But, while it has worked well for those 15 years, it is far from perfect, and for blockchain, it can be likened to the Ford T of digital trust. For one thing, it consumes lots of energy and is slow; for another, it only uses pseudo anonymisation, and once the mapping of a wallet identifier to a person is known, users can be tracked for their purchases.

Monero

For this, the Monero cryptocurrency uses a ring-signing approach, where we can bring together a number of public keys and sign a message with just one of the private keys. This makes it difficult to find the signer of a transaction, as any of the signers could be the one who signed the transaction. Let’s say we have Alice, Bob, Carol and Dave then each will apply…