Proxima. A DAG based cooperative distributed ledger
Evaldas Drasutis
TL;DR
Proxima introduces a DAG-based cooperative distributed ledger that uses a UTXO-tangle to achieve high throughput without miners or staking. By tying consensus to a biggest ledger coverage rule and leveraging incentives such as inflation, tagging-along, and delegation, token holders jointly drive forward the ledger while maintaining openness and energy efficiency. The architecture supports parallel validation, branch-based committed states, and VRF-driven randomness to mitigate bottlenecks and meta-stability, with a probabilistic safety-and-liveness framework that addresses partitions and finality. Overall, Proxima aims to combine Nakamoto-style liveness with social consensus dynamics to scale permissionless ledgers while preserving decentralization and robust security.
Abstract
This paper introduces a novel architecture for a distributed ledger, commonly referred to as a "blockchain", which is organized in the form of directed acyclic graph (DAG) with UTXO transactions as vertices, rather than as a chain of blocks. Consensus on the state of ledger assets is achieved through the cooperative consensus: an profit-driven behavior of token holders themselves, which is viable only when they cooperate by following the "biggest ledger coverage rule", akin the "longest chain rule" of Bitcoin. The cooperative behavior is facilitated by enforcing purposefully designed UTXO transaction validity constraints. Token holders are the sole category of participants authorized to make amendments to the ledger, making participation completely permissionless - without miners, validators, committees or staking - and without any need of knowledge about the composition of the set of all participants in the consensus. The setup allows to achieve high throughput and scalability alongside with low transaction costs, while preserving key aspects of high decentralization, open participation, and asynchronicity found in Bitcoin and other proof-of-work blockchains, but without huge energy consumption. Sybil protection is achieved similarly to proof-of-stake blockchains, using tokens native to the ledger, yet the architecture operates in a leaderless manner without block proposers and committee selection.