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Blockchain Technology

The traditional way of storing data was in a database, either in a structured for­

mat, referred to as the Relational Database System (RDBMS), or in an unstructured

format. Structured data would include information that could be stored in the form of

rows and columns, like address book details, booking details and so on. Unstructured

data consists of images, audio, video, Java Script Object Notation (JSON) files and

many more.

The key principle of a database is that it is centralized in nature and is controlled

by the administrator. The architecture used is the client–server architecture. There is

a chance of the data being tampered with by malicious users. Only the administrator

gives access to the users for any specific tables of the database.

There are many security concerns that arise when databases are used that could

compromise the integrity of data (Preethi et al., 2020). Wrong access privileges or

unchanged privileges could allow unauthorized users to modify or copy data from

the database. Some malware that affects the computers of the users might get access

to the database via the connected networks. Databases that have not been maintained

properly are vulnerable to exploitation. Malware, or some code that would grant

remote access to the database, could be both SQL based and NoSQL based.

In 2008, Satoshi Nakamoto developed a technology called “blockchain” that

would serve as a public transaction ledger for the cryptocurrency “bitcoin”.

9.2  BLOCKCHAIN

Blockchain is a timestamped series of immutable records of information that are

linked to one another in the form of a chain (Rosic, 2020). The fundamental feature

of blockchain is the fact that it is not managed by any individual. The links between

blocks are created using cryptographic information such as hash functions. This fea­

ture helps in maintaining the integrity of the data stored in the blocks.

Integrity can be classified as a non-functional feature of any software system

(Drescher, 2017). It consists of three major components:

• Data Integrity: Data that is used and maintained by the system must be

complete and correct and must not have any inconsistencies.

• Behavioural Integrity: The system must behave as intended and also must

be free from any logical errors.

• Security: Restricted access of data and its functionality to only authorized

users must be ensured.

Figures 9.1 and 9.2 show a single block of the blockchain. Figure 9.1 shows the struc­

ture of the block, and Figure 9.2 shows the block header.

As seen in Table 9.1, there are significant criteria for the assessment of chemical

fuels.

The block number associated with each block is a unique identifier that can be

used to distinguish blocks from each other. The block size field contains the total size

of the block, including the size of the block header and the cumulative size of the