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Blockchain Technology

is the structure within the data structure. The last hash value is stored at Merkle’s

root in the stack (Wikipedia; hash function, 2020). Figure 11.6 explains the funda­

mentals of the Merkle tree.

11.2.4.8  Model Data Record

The blockchain recognizes two main frameworks for tracking a transaction’s history:

The UTXO model and the account model. UTXO is a process that underpins Bitcoin

transaction development and authentication. Every unused output in the Bitcoin net­

work is a UTXO. The model forecast is off-axis, with less line strain. However, such

a complicated algorithm cannot be used in weak programming. In an account model,

the account holds the balance. The chain’s state is agreed as state root and receipt

root in the block. The accountability model is programmable, and the costs of mas­

sive transactions are lower (Wilson and Ateniese, 2015; Dai et al., 2017).

11.3  BLOCKCHAIN APPLICATIONS IN THE

PETROLEUM AND GAS SECTOR

Blockchain has applications in upstream, midstream and downstream sectors.

Pipelines are considered lifelines that connect the three sectors (Maccallum, 2018;

Arya and Shingan, 2012; Arya et al. 2015; Arya and Honwad, 2016, 2018a; Myalapilli

et al., 2015; Thakur et al., 2020, 2021; Gupta et al., 2018, 2019a, b). According to

Deloitte’s reports, technology has an enormous opportunity in the petroleum and gas

sector, particularly concerning four aspects: Trade, management decision, overvoice

and cyber protection (Deloitte Blockchain Overview, 2017). Figure 11.7 shows the

methodology adopted in implementing blockchain in the oil and gas sector. The fol­

lowing section discusses the potential implementation of these four elements.

FIGURE 11.6  Merkle tree.