There are several types of blockchain, each with its unique capabilities and characteristics that adapt to different needs such as: public, private, and hybrid or federated.
Blockchain technology has evolved a lot since its appearance. This evolution has caught the attention of many actors worldwide.
In its beginnings, the main stakeholders were individuals with the ability to see the transformation and the revolution it would mean . For them, it was a public technology available to everyone and, most importantly, open both to improve it and to actively participate in it.
It took some time for companies and governments to become interested in blockchain to use it in their own projects.
On the other hand, the interests of open communities are distinct from those of corporations and governments. This vision gave rise to the birth of blockchain projects unlike anything known: private blockchains and hybrid or federated blockchains.
Public blockchain
This was the first type of blockchain that existed, and refers to blockchains that anyone can freely access and join. An example of this type of blockchain is Bitcoin , Ethereum , Dash , Monero or Zcash . This type of blockchain keeps its data, software and development open to the public, so that anyone can review, audit, develop or improve them.
To achieve this, public blockchains have security measures that ensure that no malicious actor can easily alter their operation . This is where Byzantine programming fault tolerance , robust consensus protocols , DDoS protections , or 51% or double-spending attacks come into play .
In short, any measure that helps improve network security is implemented on it. The purpose of all this is to keep the network running and preserve its decentralization.
Characteristics of public blockchains
Among the characteristics of this type of networks we can mention:
Public blockchains allow anyone to be part of it . Whether as a user, miner or administrator of a node , people can access the network and be part of it without any restrictions.
The operation of the network is completely transparent and open. Blockchain data since its inception is available to everyone without restrictions. Anyone can review or audit the operation of the network and its software
There are no centralized entities. Public networks are completely decentralized and there is no central authority that regulates their operation
The economic maintenance of the blockchain depends on the system integrated into it. Generally, this economic system depends on mining and charging commissions for each transaction carried out within the network.
Private or permissioned blockchain
A growing number of businesses have begun to show an interest in blockchain technology as it continues to develop and expand. This led to the development of private or permissioned blockchain solutions .
In general, this kind of blockchain is composed of the same components as a public blockchain; however, in contrast to public blockchains, permissioned blockchains are dependent on a central unit that regulates all of the activities that take place within it.
This central unit is the one that manages access to users, in addition to controlling functions and permissions within the blockchain. Generally, they are proprietary software development options, although there are also some free software.
One of the most important private blockchain projects in the crypto world is Hyperledger . This project, initiated by the Linux Foundation and several companies in the technology sector, is the greatest example of private blockchain. We can also mention the case of Corda from R3 or Quorum from JPMorgan .
Characteristics of private blockchains
Among the characteristics of this type of networks we can mention:
Access to the network is restricted to elements that can only be authorized by the central control unit.
Access to the transaction ledger or any other means of information generated by the blockchain is private.
The economic maintenance of the blockchain development company generally depends on the company that supports the project . Private blockchains often do not have cryptocurrencies or mining actions.
Hybrid or federated blockchain
This type of blockchain is a fusion between public and private blockchains. It is an attempt to take advantage of the best of both worlds.
In these blockchains, participation in the network is private. That is, access to network resources is controlled by one or more entities. However, the ledger is publicly accessible . This means that anyone can explore block by block everything that happens on said blockchain.
For example, these types of blockchain networks are very useful for governments or business organizations that want to store or share data securely. A perfect use case is happening in the healthcare sector, where blockchain is beginning to be used to store data from its drug production lines. The stored data can be reviewed by the competent authorities in order to control quality, both at the company and government level. The objective of applying this blockchain model is to maintain a high level of transparency and trust.
Characteristics of hybrid or federated blockchains
Among the characteristics of this type of networks we can mention:
Access to the network is restricted to elements that can only be authorized by the rest of the control units.
Access to the transaction ledger or any other means of information generated by the blockchain is public.
There is no mining or cryptocurrencies . Network consensus occurs through other means that ensure that the data is correct.
It is partially decentralized which leads to a better level of security and transparency .