mirror of
https://github.com/luxfi/consensus.git
synced 2026-10-30 14:45:53 +00:00
zeekay
897e87538d
New: nebula, prism, horizon, focus, chain, formal-verification pages Updated index.mdx with full protocol listing Author: Woo Bin, Lux Network
64 lines
2.3 KiB
Plaintext
64 lines
2.3 KiB
Plaintext
---
|
|
title: Focus Consensus
|
|
description: Confidence tracking and convergence acceleration for consensus protocols
|
|
---
|
|
|
|
# Focus Consensus
|
|
|
|
Focus provides confidence tracking for consensus decisions, enabling protocols to monitor convergence progress and trigger finalization when thresholds are met.
|
|
|
|
## Overview
|
|
|
|
Focus implements a generic confidence counter system used by other consensus protocols. It tracks how many consecutive rounds a particular item has maintained majority support, enabling efficient finalization decisions.
|
|
|
|
## Core Types
|
|
|
|
```go
|
|
type Tracker[ID comparable] struct {
|
|
counts map[ID]int
|
|
}
|
|
|
|
func NewTracker[ID comparable]() *Tracker[ID]
|
|
func (t *Tracker[ID]) Incr(id ID)
|
|
func (t *Tracker[ID]) Count(id ID) int
|
|
func (t *Tracker[ID]) Reset(id ID)
|
|
func (t *Tracker[ID]) Decided(id ID, beta uint32) bool
|
|
```
|
|
|
|
## How It Works
|
|
|
|
1. **Increment**: Each round a validator confirms its preference, the confidence counter increments
|
|
2. **Reset**: If the preference changes, the counter resets to zero
|
|
3. **Decision**: When the counter reaches the beta threshold, the item is considered decided
|
|
4. **Thread Safety**: All operations are protected by read-write locks for concurrent access
|
|
|
|
## Light Metaphor
|
|
|
|
"Focus" represents the process of bringing consensus into sharp clarity — like adjusting the focus on a lens until the image becomes clear. Each round of agreement sharpens the focus until the decision crystallizes.
|
|
|
|
## Usage by Other Protocols
|
|
|
|
Focus trackers are used by:
|
|
- **Wave** — Tracks confidence in preferred transaction
|
|
- **Flare** — Monitors certificate chain confidence
|
|
- **Ray** — Confidence in DAG vertex preferences
|
|
|
|
## Configuration
|
|
|
|
| Parameter | Description |
|
|
|-----------|-------------|
|
|
| `Beta` | Confidence threshold for finalization (typically 20-30) |
|
|
|
|
## Formal Verification
|
|
|
|
Focus confidence properties are verified through Wave protocol proofs:
|
|
- **Confidence monotonicity** — proven in `Protocol/Wave.lean` (confidence_monotone)
|
|
- **Decided stability** — proven in `Protocol/Wave.lean` (decided_stable)
|
|
- See [Formal Verification](/docs/formal-verification) for full details
|
|
|
|
## References
|
|
|
|
- [Wave Protocol](/docs/wave) — Primary user of Focus tracking
|
|
- [Flare Protocol](/docs/flare) — Uses Focus for certificate confidence
|
|
- [Formal Proofs](https://github.com/luxfi/formal/blob/main/lean/Protocol/Wave.lean)
|