[Retracted] Obstetrics Nursing and Medical Health System Based on Blockchain Technology

Table 1

Comparison of characteristics of public chain, alliance chain, and private chain.

Blockchain characteristics	Public chain	Alliance chain	Private chain
Target the crowd	Anyone	Specific organization	Individual person or entity
Degree of centralization	Decentralization	Polycentric	Centralization
Incentives	Need	Optional	Not needed
Node write	Free to join	Authorization required	Internal control
Transaction speed	3–20 pens/sec	1000–10000 pens/sec	1000–10000 pens/sec
The Internet	P2P network	High-speed Internet	High-speed Internet
Node storage	Personal computer	Specific server	Specific server
Access threshold	Low	Higher	Very high
Application representative	Bitcoin blockchain; Ethereum smart contract	Hyperledger	Ant Financial
Practical field	Digital currency transactions, financial asset transactions, proof of existence, and so on	Transaction within the organization, bank or country clearing, and settlement	Companies, governments, hospitals, and other entities, used as internal information systems