The public blockchain, as we know it, is the starting point for attacks and vulnerable by its very public nature. It can be accessed, tested by anyone and the malicious can identify and attack you, including governments of some countries through agencies or institutions that already have the necessary resources. The distributed nature of public blockchains makes them difficult to secure.

Another disadvantage to public blockchains is the heavy energy consumption required to maintain them. The concern is a consensus mechanism that requires participants to compete to validate the information and receive a reward for letting the network use their processing power. Not all blockchain networks use an energy-intensive validation process, so not all use enormous amounts of electricity.

Other issues include the lack of complete privacy and anonymity. Public blockchains allow anyone to view transaction amounts and the addresses involved. If the address owners become known, the user loses their anonymity.

Public blockchains also attract participants who may not be honest in their intentions. Most public blockchains are designed for cryptocurrencies, which by nature of their value are a prime target for hackers and thieves.

Private blockchain

A private blockchain is a type of blockchain that is owned and operated by a single entity. Private blockchains are typically used by organizations or businesses that want to keep their data and transactions secure and private.

Private blockchains are different from public blockchains, which are open and permissionless, meaning anyone can access the data and transactions. Private blockchains are more secure and private, as only the entity that owns the blockchain can access and modify the data and transactions.

Private blockchains can be used for a variety of purposes, including tracking assets and data, managing supply chains, and facilitating secure payments. They can also be used to create and manage Non-Fungible Tokens (NFTs).

Some examples of private blockchains include Hyperledger Fabric, Quorum, and R3 Corda.

  • Hyperledger Fabric is an open source platform for developing enterprise-grade blockchain applications. It is designed to be flexible, scalable, and secure.
  • Quorum is an enterprise-focused version of the Ethereum blockchain. It is designed to be secure, private, and performant.
  • R3 Corda is a private blockchain platform designed to enable secure and private transactions between businesses. It is designed to be efficient and compliant with regulatory requirements.

Is a private blockchain secure?

Yes, a private blockchain can be secure if it is properly managed. Private blockchains are typically more secure and private than public blockchains, as only the entity that owns the blockchain can access and modify the data and transactions.

In order to ensure the security of a private blockchain, it is important to use encryption and authentication measures to protect the data and transactions. Additionally, the entity that owns the blockchain should have secure access protocols in place to prevent unauthorized access.

Overall, a private blockchain can be secure if it is properly managed and the right security measures are taken.


The main drawback of private blockchains is that they are more centralized than public blockchains, which means that the network is controlled by a single entity or a small group of individuals. This can lead to security issues, as the single entity or small group of individuals could potentially manipulate the data on the blockchain. Additionally, private blockchains are more expensive to operate than public blockchains, as they require more resources and infrastructure to run. This can make them inaccessible to smaller organizations and individuals. Finally, private blockchains are typically less transparent than public blockchains, meaning that users may not be able to verify the accuracy or validity of the data on the blockchain.

While purposefully designed for enterprise applications, private blockchains lose out on many of the valuable attributes of permissionless systems simply because they are not widely applicable. They are instead built to accomplish specific tasks and functions.

In this respect, private blockchains are susceptible to data breaches and other security threats. This is because there is generally a limited number of validators used to reach a consensus about transactions and data if there is a consensus mechanism.

In a private blockchain, there may not be consensus but only the immutability of entered data unless an operator or administrator can make changes.