Secure data record distribution

I. Short answer questions

What is blockchain? What are its characteristics in data storage?

What privacy issues exist in traditional Bitcoin transactions? How to solve them?

How does CoinJoin transactions improve the anonymity of Bitcoin? What are its limitations?

For which data record distribution scenarios has it been improved?

What do "input node" and "output node" refer to in?

Briefly describe the role of the elliptic curve digital signature algorithm (ECDSA) in blockchain.

What is a threshold signature scheme? How does it enhance data security?

Explain the concept and role of "Secret Share Joining".

What role does "stealth address" play in in?

Briefly describe the two stages of data record distribution in in.

II. Answers

Blockchain is a decentralized distributed ledger technology that is composed of blocks. Its characteristics include decentralization, transparency, security and immutability, which ensures the safe and reliable storage of data.

Traditional Bitcoin transactions publicly record all transaction information, including the addresses of both parties to the transaction, which can be easily tracked and analyzed, resulting in privacy leaks. Solutions include using methods such as currency mixing technology and stealth addresses.

CoinJoin transactions mix the transaction inputs and outputs of multiple users, making it more difficult to track transactions and improving anonymity. However, its limitation is that some participants still know part of the input-output relationship, and security is limited.

For scenarios where data records need to be distributed securely and immutably, such as exams or document submissions, anonymous crime reports, anonymous questionnaires, etc.

"Input nodes" refer to participants who provide data records, while "output nodes" refer to participants who receive data records. They participate in the data distribution process by controlling their respective blockchain addresses.

ECDSA is an encrypted digital signature algorithm used to ensure that only legitimate owners can use the value associated with UTXO. It ensures transaction security through private key signatures and public key verification.

The threshold signature scheme divides the key into multiple parts and distributes them to multiple participants. Only when a predetermined number of participants work together can the key be reconstructed and the signing operation be performed to enhance data security.

"Secret sharing participation" refers to multiple participants jointly calculating a value based on a shared secret without revealing their respective key shares. This technology is often used in threshold signature schemes.

"Stealth address" is a temporary address generated by the receiver and used by the sender to hide the real receiving address, prevent transactions from being linked, and improve the anonymity of transactions.

In the first stage, the input node sends the data record to a jointly determined stealth address; in the second stage, the output node extracts the data record from the stealth address and distributes it to their respective output addresses.

III. Discussion Questions

Compare and contrast the advantages and disadvantages of the traditional centralized data record distribution system and the blockchain-based distribution system.

Explain in detail how to use threshold signature schemes and stealth address technology to achieve secure data record distribution.

Analyze the advantages of privacy protection compared to CoinJoin transactions.

What specific real-world scenarios can the data record distribution method mentioned be applied to? And discuss its potential social impact.

For the data record distribution method mentioned in, explore its improvement direction in terms of efficiency and security.

IV. Glossary

Term Definition Blockchain (Blockchain) is a decentralized distributed ledger technology that records transaction information in the form of blocks, with the characteristics of transparency, security, and non-tamperability. Stealth Address is a temporary address generated by the receiver and used by the sender to hide the real receiving address and improve the anonymity of the transaction. Threshold Signature Scheme is a key that is divided into multiple parts and distributed to multiple participants. Only when a predetermined number of participants work together can the key be reconstructed and the signature operation be performed. Secret Share Joining is a value based on a shared secret that is jointly calculated by multiple participants without revealing their respective key shares. Elliptic Curve Digital Signature Algorithm (ECDSA) is an encrypted digital signature algorithm used to ensure that only the legitimate owner can use the value associated with UTXO. Input Node is a participant who provides data records and participates in data distribution by controlling its blockchain address. Output Node is a participant who receives data records and participates in data distribution by controlling its blockchain address. Data Record refers to any type of data that needs to be distributed securely and tamper-proof, such as test answers, documents, anonymous reports, etc. Non-Transaction Code is a special code used to mark non-transaction data in blockchain transactions, such as OP_RETURN in the Bitcoin protocol. Shared Secret is a part of secret information held by multiple participants, which can be used to generate stealth addresses or perform threshold signature operations.