Solana: A New Architecture for High-Performance Blockchain

Abstract

This white paper introduces Solana's innovative blockchain architecture built on Proof of History (PoH)—a cryptographic method for verifying event order and time passage without trust. When combined with consensus mechanisms like Proof of Stake (PoS), PoH minimizes messaging overhead in Byzantine Fault Tolerant systems, enabling sub-second finality. The paper also presents:

• A PoS algorithm resilient to network partitions.
• An efficient streaming Proof of Replication (PoRep) for storage verification.

Benchmarked on a 1 Gbps network, Solana achieves 710,000 transactions per second (TPS) with current hardware.

Key Innovations

1. Proof of History (PoH)
   Encodes time passage into a tamper-proof ledger, enabling verifiable event ordering.
2. Optimized Consensus
   Reduces latency by leveraging PoH’s timekeeping for PoS voting.
3. Streaming PoRep
   Combines with PoH to defend against ledger forgery in time and storage.

1. Introduction

Traditional blockchains lack a trusted time source, relying on local clocks that may disagree. PoH solves this by creating a cryptographic record of time that all nodes can verify independently.

2. System Design

Network Components

• Leader: Generates PoH sequences and orders transactions.
• Verifiers: Replicate state and validate transactions.
• Validators: Participate in PoS consensus.

Performance Highlights

• Throughput: 710k TPS (1 Gbps network).
• Finality: Sub-second via PoH + PoS synergy.

3. Proof of History (PoH)

How It Works

1. Sequential Hashing:
   A cryptographic hash function (e.g., SHA-256) runs iteratively, with each output becoming the next input.

   Example:
   - Hash1 = SHA256("seed")
   - Hash2 = SHA256(Hash1)
   - HashN = SHA256(HashN-1)

2. Timestamping:
   Data (e.g., transactions) is appended to the sequence, altering future hashes to prove its existence before subsequent events.

Verification

• Parallelized across multicore systems (e.g., GPUs) for efficiency.
• Horizontal scaling possible via synchronized PoH generators.

4. Proof of Stake Consensus

Key Features

• Bonding: Validators stake tokens as collateral.
• Slashing: Malicious votes result in lost stakes.
• Elections: Leader rotation based on stake weight.

Attack Mitigations

• Long-Range Attacks: PoH’s time-bound ledger prevents historical rewriting.
• Censorship: Dynamic bond unstaking penalizes partitions.

5. Streaming Proof of Replication (PoRep)

Algorithm

1. CBC Encryption: Data encrypted sequentially (each block depends on the prior).
2. Merkle Proofs: Random block segments hashed with PoH-derived seeds.
3. Key Rotation: Periodic re-encryption to prevent replay attacks.

Verification

• GPU-accelerated for scalability (~3500 cores).
• Hash Selection: PoH-published hashes ensure unbiased randomness.

6. System Architecture

Components

• Leader: Orders transactions into PoH sequences.
• State: Optimized hash table (10B accounts in 640GB RAM).
• Verifiers: High-availability replication nodes.

Limits

• Network: 710k TPS (176-byte tx size).
• Compute: 900k ECDSA verifications/sec (GPU).

FAQ

Q1: How does PoH improve blockchain performance?

PoH eliminates redundant messaging in consensus by providing a trusted time source, reducing latency and enabling high throughput.

Q2: What prevents validators from approving invalid states?

Random invalid hashes injected by the Leader trigger slashing if approved, ensuring active validation.

Q3: How does Solana handle network partitions?

Dynamic bond unstaking favors larger partitions, enabling recovery while penalizing malicious actors.

Q4: Is Solana resistant to ASIC attacks?

PoH’s sequential work requirement and slow unstaking rates make ASIC gains marginal.

Q5: What’s the role of PoRep?

PoRep ensures storage integrity by requiring nodes to prove they retain encrypted data, validated via PoH-tied proofs.

👉 Explore Solana’s Whitepaper for technical details.
👉 Learn about PoH’s cryptographic guarantees.