# Information and Communication Technology Solutions for the Circular Economy
## 2 Information and Communication Technology Solutions for the Circular Economy
### Data Management and Storage  
Data management and data storage technologies were adopted within various solutions that were analyzed for this literature review, e.g., information management systems (IMS), blockchain, data privacy, data security, smart contracts. The use of these technologies is further elaborated below.  
An IMS can be defined as a software system responsible for data storage, searching and retrieval [78]. [PERSON] presents an IMS applied to tourism management in order to cover CE purposes. Some potential benefits of such a solution include more efficient information tracking and processing, improved security and customer relationships, as well as better control of supplies [79]. Together with various other solutions, [PERSON] et al. underscore the importance of relational database management systems (RDBMS) and database handling systems in waste handling, where they facilitate decision-making, leading to the re-planning of the value network [80]. [PERSON] et al. present main defense mechanisms for providing end-to-end data security and privacy, facilitating the integration of big data, Internet of Medical Things (IoMT) with the CE and contributing to the optimized use of assets [81].  
Blockchain is an increasingly popular technology in the area of data management and storage. As expected, this technology has also raised the attention of CE researchers. Blockchain can be defined as \"a distributed ledger maintaining a continuously growing list of data records that are confirmed by all of the participating nodes\" [82]. A block is a record which contains data, a value with the hash (digital fingerprint of an amount of data of the block) of the previous block, and a value that represents its own hash. The meaning of the cryptographically linked chain of blocks through these hashes can be explained by the link between the hash of the current block and the hash of the previous block [83]. [PERSON] et al. analyze the potential to improve the effectiveness of the organic food supply chain, using the blockchain technology [84]. [PERSON] et al. explore cases in which blockchain technology enabled traceability, and thus improved handling of electronic waste [85].  
In conjunction with blockchains, smart contracts have been attracting significant research attention from the scientific community. A contract can be defined as a set of rules or clauses that parties have agreed upon, for governing the relationship between them. Smart contracts are just like contracts in the real world, with the difference that they are fully digital. They are small script programs, which are used and stored in blockchains, featuring a tamper-proof logic code within them [83]. [PERSON] et al. describe a solution for regulated circular healthcare jurisdictions using the blockchain and smart contract technologies. Such a solution has the potential to contribute to more modular and interoperable healthcare services as well as to enable circularity by providing the necessary collaborating mechanism [86].