Blockchain Access Control System Study Guide

Authentication Confidential Data Collaboration System for Blockchain

Short Answer Question

Describe some inefficiencies in confidential collaboration in the prior art.

Why is static trust chain unsuitable for confidential collaboration?

Explain the concept of dynamic trust chain and how it addresses the limitations of static trust chain.

What role does C-forward (authenticated forward) play in multi-party confidential transactions?

How does authentication thread support the concept of versioned entities, such as orders or wills?

Explain the purpose of C-ReadAck (authenticated read confirmation) and provide a use case example.

How does smart template differ from smart contract?

Describe the role of fat twin and thin twin in authentication thread.

What is the purpose of QQCoin token in this invention?

Explain how the proxy re-encryption scheme is used to achieve end-to-end encryption in this invention.

Short Answer Question

Confidential collaboration in the prior art suffers from lack of visibility, deniability, data fragmentation, and data inconsistency. For example, in the healthcare industry, prescription sharing between patients, doctors, and pharmacies can be inefficient and error-prone.

Static trust chains are unsuitable for confidential collaboration because they require trust relationships to be established in advance and do not consider the context of the information. For example, in the prescription example, the pharmacy cannot trust every patient to forward the doctor's prescription without tampering.

A dynamic trust chain relies on pre-established trust that does not rely on any intermediaries. In blockchain terms, this chain consists of "trustless" intermediaries, meaning that trust is not established in advance but cryptographically guaranteed at the time of each transaction.

C-forward (certified forward) enables a second level of decentralization in multi-party confidential transactions by allowing one party to share a certified copy of a certification thread with another party. This allows the parties to verify the transaction without having to trust an intermediary.

Certified threads support versioned entities by storing an immutable, append-only record of all changes. Each change becomes a new version of the thread state, ensuring that all parties have access to the latest certified state and complete history.

C-ReadAck (certified read acknowledgement) allows a party to authentically confirm that they have read a specific message or set of changes in a certification thread. For example, in a contract negotiation, both parties can use C-ReadAck to prove that they have reviewed the latest version.

Smart templates are defined declaratively by business people to automate structured and unstructured collaboration, while smart contracts are created by software developers in an imperative coding style for permission-based code contracts.

Fat twins contain the complete confidential information of the authentication thread and are maintained off-chain by the regulator. Thin twins are stored on the public blockchain and contain publicly verifiable information used to verify transactions and enable authentication proofs.

QQCoin tokens are designed to create an incentive mechanism to promote the smooth operation of. They are used as a means to pay regulator service fees, smart template instantiation fees, and various value-added service fees.

Proxy re-encryption schemes allow senders to encrypt information so that only authorized receivers can decrypt, ensuring that even regulators cannot access the underlying data. The sender generates a changeset key that is used to encrypt the specified content. This key is then re-encrypted with the receiver's public key, allowing them to decrypt the content when they access the thread.

Key Glossary

Term Definitions Authentication Thread A tamper-proof communication or collaboration thread where the content, timestamps, and identities are cryptographically verified. Changeset An update to an authentication thread that creates a new version of the thread state. C-forwardThe operation of creating an authenticated copy of an authentication thread, preserving its history and establishing a dynamic chain of trust. Smart TemplatesInstantiable templates for defining reusable authentication thread patterns (such as orders, contracts, or forms). Fat TwinA complete confidential representation of an authentication thread maintained off-chain by a regulator. Thin TwinA publicly verifiable representation of an authentication thread stored on a public blockchain, containing hash information for verification. A regulator is a semi-trusted party responsible for verifying transactions, maintaining fat twins, and synchronizing on-chain and off-chain information. QQCoin TokenA protocol token used to facilitate incentives and payments within the ecosystem. Proxy Re-encryptionAn encryption scheme that allows one party to re-encrypt encrypted data so that another party can decrypt it without decrypting it. Dynamic Trust ChainA trust model in which trust is not established in advance but is cryptographically guaranteed at the time of each transaction.