Chapter 6: Private and Hybrid Blockchains and Applications

This chapter focuses on blockchains that are not fully public, specifically hybrid and private blockchain models and applications. It begins by reviewing a general framework of blockchain technology used to define and differentiate the two types of blockchain from each other and from a public blockchain. The chapter then discusses several applications as illustrative examples of the differences.

This chapter does not distinguish between distributed ledger technology (DLT) and blockchain, despite the fact that all blockchains are DLTs, but not all DLTs are blockchains. Any system based on DLT consists of three layers ‒ (1) protocol, (2) network, and (3) data ‒as represented in Fig. 6.1 and adapted from Rauchs et al. (2018). The protocol layer is tasked with providing and updating the set of software-defined rules to determine how the system operates. Next, the network layer connects actors, data, and processes according to the implemented protocol layer. Finally, the data layer comprises the information flowing through the system and the relation of the data to the protocol and network layer.