Adamastor: a New Low Latency and Scalable Decentralized Anonymous Payment System
This paper presents Adamastor, a new low latency and scalable decentralized anonymous payment system, which is an extension of Ring Confidential Transactions (RingCT) that is compatible with consensus algorithms that use Delegated Proof of Stake (DPoS) as a defense mechanism against Sybil attacks. Adamastor also includes a new Decoy Selection Algorithm (DSA) that can be of independent interest, called SimpleDSA, a crucial aspect of protocols that use ring signatures to anonymize the sender. SimpleDSA offers security against homogeneity attacks and chain analysis. Moreover, it enables the pruning of spent outputs, addressing the issue of perpetual output growth commonly associated with such schemes. Adamastor is implemented and evaluated using the Narwhal consensus algorithm, demonstrating significantly lower latency compared to Proof of Work based cryptocurrencies. Adamastor also exhibits ample scalability, making it suitable for a decentralized and anonymous payment network.