Design Overview

This design augments the existing Zcash Proof-of-Work (PoW) network with a new consensus layer which provides trailing finality, called the Trailing Finality Layer (TFL).

This layer enables blocks produced via PoW to become final which ensures they may never be rolled back. This enables safer and simpler wallets and other infrastructure, and aids trust-minimized cross-chain bridges.

This consensus layer uses a finalizing Proof-of-Stake (PoS) consensus protocol, and enables ZEC holders to earn protocol rewards for contributing to the security of the Zcash network. By integrating a PoS layer with the current PoW Zcash protocol, this design specifies a hybrid consensus protocol.

The integration of the current PoW consensus with the TFL produces a new top-level consensus protocol referred to as PoW+TFL.

In the following subchapters we introduce the Design at a Glance, then provide an overview of the major components of the design.

Following this overview chapter, we proceed into a detailed Protocol Specification (TODO).