A minimal reimplementation of the Tendermint BFT consensus protocol in Rust.
Dependencies:
- tokio - for async runtime.
- secp256k1 - for cryptographic identities.
- serde - for message serialisation.
- warp/reqwest - for HTTP server/clients (for node RPC).
- hex.
A consensus protocol consists of a set of processes, which communicate by sending messages to each other in order to agree on a value. Processes may crash, run at arbitrary speeds, and display byzantine failures. The challenge of consensus is building a protocol which can finalise and does so safely and consistently given these assumptions.
The basic Tendermint algorithm is implemented as Process. Each Process communicates via abstract channels - there is an implementation using just local communication (examples/standalone-channels), and an implementation using RPC over HTTP servers (examples/standalone-http). Processes emit consensus events via tokio async streams - consumers can subscribe to the process and receive callbacks for new values agreed on by the network (called "decisions"). Each node has an ECDSA keypair it uses to sign messages.
Protocol runs and achieves consensus, with rounds, epochs.
See PLAN for the backlog.
cargo build
cargo run --example standalone-channels
cargo run --example standalone-httpRust Tendermint can be used to build a consistent and partition-tolerant network, with a custom value that is agreed per epoch, and event streams which allow you to consume different events (such agreement - referred to as a decision, and intermediate stages).
use tendermint::Process;
fn example() {
// Setup networking substrate between nodes.
let node = Process::new();
// Pass a get_value callback to get the next candidate value for proposal.
// Subscribe and listen to Decision events to process them.
}See examples/.