In order to formalize Distributed Ledger Technologies and their interconnections, a recent line of research work has formulated the notion of Distributed Ledger Object (DLO), which is a concurrent object that maintains a totally ordered sequence of records, abstracting blockchains and distributed ledgers. Through DLO, the Atomic Appends problem, intended as the need of a primitive able to append multiple records to distinct ledgers in an atomic way, is studied as a basic interconnection problem among ledgers. In this work, we propose the Distributed Grow-only Set object (DSO), which instead of maintaining a sequence of records, as in a DLO, maintains a set of records in an immutable way: only Add and Get operations are provided. This object is inspired by the Grow-only Set (G-Set) data type which is part of the Conflict-free Replicated Data Types. We formally specify the object and we provide a consensus-free Byzantine-tolerant implementation that guarantees eventual consistency. We then use our Byzantine-tolerant DSO (BDSO) implementation to provide consensus-free algorithmic solutions to the Atomic Appends and Atomic Adds (the analogous problem of atomic appends applied on G-Sets) problems, as well as to construct consensus-free Single-Writer BDLOs. We believe that the BDSO has applications beyond the above-mentioned problems.
翻译:为了正式确定分布式Ledger技术及其相互联系,最近一行的研究工作提出了分配式Ledger 对象的概念,这是一个同时维持完全有序的记录序列、抽象的块链和分布式分类账的物品。通过 DLO,原子附加问题,即一个能够以原子方式将多种记录附加到不同分类账的原始需要,作为分类账之间一个基本的互联问题进行研究。在这项工作中,我们提议“分配式只增长式天体(DSO)”,该天体不是像 DLO那样维持记录序列,而是以不可改变的方式维持一套记录:只提供添加和获取操作。这个目标受到“只增长式”数据类型(G-Set)的启发,这是无冲突复制数据类型的一部分。我们正式指定该对象,我们提供一种没有共识的Byzantine-容忍性执行方式,以保证最终的一致性。我们随后使用我们的Byzant-容忍式 DSO(BDSO) 来提供一套不可更改式的算法应用方法,作为B-SAP-S-SAP-S-Atols reflistal Anolistal Ann Atolsmals-st Applistal-stal Applistal Applistels-tols) 问题,我们将无核应用了B-tols-tob-tols-tols-tols-tols-tols-tob-tols-tols-tols-tols-tols-tols-tols-tols-to-to-to-tob-toal-tols-tols