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Firo Blockchain Architecture

A hybrid Proof-of-Work and masternode system that delivers fast confirmations, strong security, and decentralized governance.

Hybrid PoW + Masternode Consensus

Firo uses a two-layer consensus model that combines the strengths of Proof-of-Work mining with a masternode network:

Layer 1: FiroPoW Mining

GPU miners run the FiroPoW algorithm (a modified ProgPoW) to produce blocks. This ensures decentralized block production resistant to ASICs. The DAG size exceeds 7 GB, requiring modern GPUs with 8+ GB VRAM.

Layer 2: LLMQ Masternodes

Over 3,900 masternodes (each requiring 1,000 FIRO collateral) form Long Living Masternode Quorums (LLMQs). They provide ChainLocks for instant finality and protect against 51% attacks and chain reorganizations.

ChainLocks (Instant Finality)

ChainLocks is one of Firo's most important security features. Here's how it works:

  1. A miner produces a new block and broadcasts it to the network
  2. A quorum of masternodes evaluates and signs the block using BLS threshold signatures
  3. Once a supermajority of the quorum signs, the block is "locked" — it becomes the definitive chain tip
  4. Any competing chain (even with more cumulative work) is rejected, preventing 51% attacks

Why This Matters

Traditional PoW chains like Bitcoin can theoretically be attacked if someone controls 51% of hash power, leading to double-spends. ChainLocks makes this impossible on Firo — an attacker would need to control both the majority of mining power AND the majority of masternodes simultaneously.

Network Specifications

Block Time
~5 minutes
Mining Algorithm
FiroPoW (GPU)
DAG Size
> 7 GB
Masternodes
3,900+
Masternode Collateral
1,000 FIRO
Instant Finality
ChainLocks (LLMQ)
Total Supply
21.4 million
Privacy Protocol
Lelantus Spark
51% Protection
ChainLocks

Network-Level Privacy

Beyond protocol-level privacy (Lelantus Spark), Firo also implements Dandelion++ for network-level protection. This protocol obscures the IP origin of transactions by first routing them through a random series of nodes before broadcasting to the wider network.

This prevents network observers from determining which node originated a transaction, providing an additional layer of privacy that complements Spark's on-chain protections.

Participate in the Network

Help secure the Firo blockchain by mining or running a masternode.