# Comparing Blockchain Standards and Recommendations
## 2 Background & Related Work  
### Related Concepts  
During our research, we found a couple examples of work focusing on standardization of distributed ledgers. Starting with the first one, _Permissioned Distributed Ledger (PDL); Landscape of Standards and Technologies_[8], a group report from ETSI. It is part of an Industry Specification Group working on distributed ledgers which is not limited to standardization activities and therefore includes research activities and initiatives concerning blockchain and the distributed ledger as well. The document states that distributed ledger technology could have great potential, underlined with a selection of possible fields of usage in various domains. Its core, however, is the discussion of current standardization and research activities. Since we focus on standardization activities in this paper, the first part is of special interest to us. Standardization activities are relatively underrepresented compared to the other content, which suggests that at the time there was only a limited amount of efforts on blockchain and DLT standardization. Furthermore, the presented information consists of a list of organizations and a description of the general working direction and does not include an analysis of the published work itself. The document also mentions regulatory aspects and difficulties that could arise for distributed ledger technologies. Additionally, it includes a short list of different data structures for ledgers and a substantial overview of research and innovation projects on the matter.  
The second related work is the _Distributed ledger technology standardization landscape_[9] technical report by ITU-T Focus Group on Application of Distributed Ledger Technologies (FG DLT). This document focuses on the standardization landscape, not including research or industrial initiatives. The core part of this report mainly consists of an in-depth overview of the cumulative activities of study groups at ITU-T, including not only the FG DLT, but also focus groups with similar research directions but differentiating main topics. These include for example focus groups on the internet of things and smart cities, and digital financial services. The overview of other bodies of standardization is more detailed than in [8]. Nonetheless, the work done by ITU-T in this report is still in the form of an enumeration of standardization activities, without evaluating the content of the mentioned documents.  
In [10], the authors point out the importance of blockchain standardization to overcome a number of problems. Furthermore, they provide an overview of standardization efforts of international organizations from early 2016 which includes ISO, IEEE, ITU and W3C. At the time of publication of this source, none of these organisations have produced publications and are merely at an early formation stage of several working groups. In the article it becomes apparent however, that standardization of blockchain technologies is of national interest for China.  
Our own research differs from these related work examples in multiple ways. For one, the number of included standardization activities is more thorough than those of the previous examples. Not only concerning the state of published work, which could be easily explained by acknowledging the point in time of the research, but also because we include several organizations that had been left unmentioned previously because they are more relevant for the field of information security instead of distributed ledger technology. Second, the core of this paper is not to simply provide a list of existing documents, but rather to look at their contents. As already mentioned in the introduction 1, we focus on providing a thorough catalogue of criteria to compare and analyze the presented standardization efforts.