# Comparing Blockchain Standards and Recommendations
## 4 Selected Standards
### German Institute for Standardization (DIN)  
At the time of this research, the German Institute for Standardisation has published a number of specifications relating to blockchain technology and distributed ledgers. * DIN SPEC 16597 [22]: DIN provides a _terminology for blockchains_ with this specification. It aims at being relevant for a broader audience and not bound to a single usage area or industrial sector. It covers terminology from traditional IT and cryptography before delving into blockchain specifics. This terminology is referenced in the other specifications mentioned here and part of a larger industry cooperation project Pros: The provided terminology is good to get into blockchains and understand the individual components. Cons: It is used as a preliminary for the other documents and therefore missing out on \"out of scope\" elements. * DIN SPEC 3103 [23]: The specification _Blockchain and Distributed Ledger Technologies in Application Scenarios for Industry 4.0_ presents application scenarios for the technology in the field of modern industry. The presented information should provide decision makers with enough information to evaluate a possible benefit of introducing distributed ledger technology. The document presents a number of use cases and describes respective problems that can occur. These problems then get addressed by introducing a solution by using blockchains/distributed ledger technology, including user stories and sequence diagrams to reinforce the understanding. Reoccurring elements of these scenarios are then formed to be building blocks, which get expounded accordingly so it can be used for other use cases as well. Pros: This document provides a proper outlook and guideline for industry 4.0 Cons: Outside of that its use can be rather limited. * DIN SPEC 3104 [24]: In their specification about _blockchain-based validation of data_, they heavily focus on data correctness of blockchains. To achieve what they call _Proof of Correctness_, they propose a technical framework and process descriptions for a blockchain validation software and the verification of this validation. Their technical framework comes in the form of a step by step overview where each block or process is explained and what its requirements are. Pros: They provide a guiding framework for \"blockchain-based validation of data\" Cons: It is not particularly useful for a more generalised approach on the technology. * DIN SPEC 4996 [25]: SPEC 4996, _blockchain-based approach to the transfer of software licenses_, focuses on providing for the establishment of a standardized procedure for digital trade, transfer and management of software licenses using distributed ledger technology by determining a set of requirements. Additionally, they define required information elements to conduct software and licensing operations. The specification informs the reader on how the transparency and tamper-proof attributes of a blockchain can be used to prevent loss or multiple usage of one license. An overview of various roles involved in licensing operations is explained, as well as a design overview of how a proposed system could look like. Pros: They provide a guiding framework for a \"blockchain-based transfer of licenses\" Cons: It is not particularly useful for a more generalised approach on the technology. * DIN SPEC 4997 [26]: The specification _Privacy by Blockchain Design: A standardized model for processing personal data using blockchain_ concerns itself with the EU General Data Protection Regulation (GDPR), especially _art. 25, Privacy by design_. The aim of this specification is to support data protection and privacy compliance in blockchain/distributed ledger technology systems. It is explained what personal data means and how such information can be identified. This is reinforced by stating a number of possibilities where personal data can be found and where it is processed. The specification lists concerns of combining blockchains with the GDPR and which legal issues it might bring like ownership and data erasure.