Bitcoin Thunderbolt Protocol: Reshaping Bitcoin Off-Chain Interaction Paradigm

1. The Transaction Efficiency Dilemma of Bitcoin

Although Bitcoin is known for its decentralization and immutability, it faces serious efficiency issues in everyday payment scenarios. Factors such as long transaction confirmation times and high fees make small payments using Bitcoin impractical. The liquidity of assets on Bitcoin is limited, making it difficult to achieve flexible financial operations. These limitations mainly stem from Bitcoin's conservative script structure design, which cannot meet the demands of high-frequency payments.

2. Lightning Network: A Solution That Has Not Fully Solved the Problem

The Lightning Network aims to enhance the transaction efficiency of Bitcoin by establishing off-chain payment channels. It transfers a large number of small transactions off-chain, synchronizing with the main chain only when the channels are opened and closed. This model is similar to friends accumulating multiple expenses and settling once.

However, the Lightning Network has exposed several issues in practice:

1. The threshold for establishing a channel is high, requiring funds to be locked in advance.
2. Complex routing issues, indirect payments are prone to failure.
3. High security risks, requiring users to remain online.

These structural flaws have resulted in the limited scale of applications for the Lightning Network. Currently, the total amount of funds locked in the entire network is only about 100 million dollars, which is negligible compared to the total market value of the Bitcoin system.

3. Innovation of the Thunderbolt protocol

The Thunderbolt protocol is a soft fork upgrade to the underlying Bitcoin, which directly enhances the scalability, performance, and programmability of the main chain.

Main innovations include:

1. UTXO Bundling technology: Aggregating multiple UTXOs to improve transaction speed by about 10 times.

2. Extended OP_CAT opcode: Enhances scripting capabilities to support more complex smart contract logic.

3. Goldinals Unified Asset Standard: A native token issuance framework based on zero-knowledge proof.

4. BitMM on-chain automated market maker: Integrates various protocol assets.

5. BitVisa Decentralized Identity System: Provides verifiable credential services.

Thunderbolt adopts the "main chain native expansion" approach, with all functions implemented directly on the Bitcoin main chain, without relying on side chains or cross-chain bridges.

4. Core Mechanism Analysis

The core mechanism of Thunderbolt includes:

1. Flexible and adjustable multi-signature: Split the signature into user parts and committee parts, achieving non-interactive transfer through secret sharing.

2. Asynchronous fault-tolerant committee ledger: A service group composed of multiple nodes is responsible for bookkeeping, ensuring decentralization and security.

3. Atomic Swap Finalization: Ensure the consistency of off-chain reconstruction and on-chain redemption through a three-step atomic swap process.

Main technological innovations:

• Non-interactive, recursive signature delegation
• Update signature for each transfer
• Minimize on-chain operations
• Offline Security Guarantee
• The security of formal verification

5. Comparison with Existing Lightning Network Solutions

Advantages of Thunderbolt compared to existing solutions:

• It can be theoretically proven to be secure.
• Prevent malicious users from profiting unilaterally

Disadvantages:

• Deployment is complex and requires running a complete protocol stack.
• Limited main chain compatibility
• The ecological support is still not完善.

6. The Potential Impact and Development Path of Thunderbolt

Thunderbolt is considered the theoretically optimal solution in the BTCFi field, but it is still in the early stages. Its possible development paths include:

1. Integrated into the Bitcoin L2 solution
2. Form an independent standard ecosystem
3. Replaced by simpler technical solutions

The greatest significance of Thunderbolt lies in bringing off-chain contract composability to Bitcoin assets, which may become the key to the explosion of the Bitcoin DeFi ecosystem. However, there is still a long way to go from theoretical design to practical application.