public Blockchains are called public blockchains that have no access restrictions. Anyone with computers or internet connections can send and validate transactions and can take part in executing a consensus protocol.
Autonomy: No individual or company is able to control the blockchain information or the blockchain rules.
Publicity security: Since every participant is able to see all balance of accounts and transactions information, none attempts any illegal activityto secure the blockchain in order to be caught in it.
Availability: There are easy public blockchains for people to use since there are no restrictions on access.
Limited scalability, limited privacy and lack of official contract verification, storage limitations, unsustainable consensus mechanisms, insufficient management and standards, inadequate tools and quantum computing threats, etc. all have the disadvantages of a public blockchain.
A private blockchain is a permission. It is impossible to join if the network administrators do not invite you. In this type of blockchains, Participant and validator access is limited. These blockchains can be regarded as a centerpiece for companies which generally have an interest in blockchain technology, but are not convenient with public blockchains ‘ control level. Typically, they attempt to integrate blockchain in their accounting methods, without sacrificing autonomy and without risking Internet exposure to sensitive data.
- Transaction speed: The private blockchain transaction speed is usually faster than a public blockchain as there are fewer cross points of high confidence that have been established at all and no need to verify a transaction for each cross-point.
- Flexibility: if necessary, the blockchain rules may be changed; transactions may be reversed; the company owning the blockchain may change balances.
- Transaction cost: The costs of proven blockchain transactions are lower in comparison to public blockchains and can sometimes be even free.
- A chance to survive: The most important advantage of private blockchains is that organizations that implement private blockchains can protect their fundamental program from destruction.
Private blockchain’s disadvantages include stunted growth, control, and manipulation, hard to access and use, and so on.
A blockchain consortium is a blockchain, in which a preset set of nodes, controlled by a consortium of partners, controls the consensus process. Rather than having no control over it at all or having a single point of control, a blockchain consortium offers a mid-way through maintaining the power of control within a group of the members. Consortium blockchains are also considered as partly decentralized due to the above concept.
Eg: Quorum, Hyperledger, and Corda.
A consortium platform reduces transaction costs and data redundancies, replaces legacy systems, simplifies document handling and eliminates semi-manual compliance mechanisms.
The disadvantages of consortium blockchain are same as that of private blockchains.