流体公证：并发编辑的结构化文档的可验证演化
Fluid Notarization: Verifiable Evolution of Concurrently Edited Structured Documents
- University of Applied Sciences and Arts of Southern Switzerland (SUPSI)（南方瑞士应用科学与艺术学院）
机构由 AI 辅助整理，请以论文原文为准。
中文总结 AI 辅助
本文提出流体公证范式，通过JSON原生delta-CRDT生成因果演化图并链上记录标识符，实现并发编辑文档的确定性收敛与可审计存在性证明，优于传统快照公证。
中文摘要 AI 辅助
传统的基于区块链的文档公证遵循快照导向模型，其中每个文档修订版被表示为通过密码学引用锚定在链上的独立状态。虽然这种方法对不可变工件有效，但当文档通过协作编辑演化时，这种方法变得不足。并发修改会产生分叉的文档版本，这些版本必须在公证层之外进行协调，而即使是微小的更改也需要生成和分发新的文档快照。相反，诸如CRDT之类的协作复制框架提供了并发更新的确定性协调，但本身并不提供关于贡献何时发布的独立可验证证据。本文介绍了流体公证，一种公证范式，其中文档演化本身成为公证的对象。流体公证不是认证孤立的状态，而是认证由JSON原生的delta-CRDT生成的因果相关演化工件图。所提出的模型建立在Melda之上，Melda将文档更改表示为通过因果依赖链接的紧凑的、内容寻址的增量。区块链公证被简化为记录这些演化工件的标识符，而同步、重建和冲突解决完全保持在链下。由此产生的架构结合了两种互补的保证：由CRDT提供的确定性收敛和由区块链提供的独立可审计的存在性证明、来源和发布证据。基于协作编辑的电子健康记录的原型实现和验证场景证明了该方法的可行性，并突出了公证文档演化而非连续文档快照的优势。
英文摘要
Traditional blockchain-based document notarization follows a snapshot-oriented model in which each document revision is represented as an independent state anchored on-chain through a cryptographic reference. While effective for immutable artifacts, this approach becomes inadequate when documents evolve through collaborative editing. Concurrent modifications create divergent document versions that must be reconciled outside the notarization layer, while even minor changes require generating and distributing new document snapshots. Conversely, collaborative replication frameworks such as CRDTs provide deterministic reconciliation of concurrent updates, but do not inherently provide independently verifiable evidence of when contributions were published. This paper introduces Fluid Notarization, a notarization paradigm in which document evolution itself becomes the object of notarization. Rather than certifying isolated states, Fluid Notarization certifies a graph of causally related evolution artifacts generated by a JSON-native delta-CRDT. The proposed model builds upon Melda, which represents document changes as compact, content-addressed deltas linked through causal dependencies. Blockchain notarization is reduced to recording identifiers of these evolution artifacts, while synchronization, reconstruction, and conflict resolution remain entirely off-chain. The resulting architecture combines two complementary guarantees: deterministic convergence provided by the CRDT and independently auditable proof-of-existence, provenance, and publication evidence provided by the blockchain. A prototype implementation and validation scenario based on collaboratively edited electronic health records demonstrate the feasibility of the approach and highlight the advantages of notarizing document evolution rather than successive document snapshots.
