Types of Blockchains: Public, Private, and Consortium

Well done on your progress so far! You’re now familiar with the key components of a blockchain
and how it works. In this lesson, we’ll explore the different types of blockchains: Public, Private,
and Consortium. Understanding these types is essential as they each serve different purposes
and are used in various applications.
Public Blockchains
Public blockchains, also known as permissionless blockchains, are open to anyone who wants
to participate. Anyone can become a node, validate transactions, and add new blocks to the
chain. Public blockchains are fully decentralized, meaning there’s no central authority that
controls the network.
Here are some key features of public blockchains:
Open Participation: Anyone can join the network, validate transactions, and add new
blocks to the chain.
Transparency: All transactions are visible to everyone in the network, promoting
transparency and trust.
Security: Public blockchains use robust consensus mechanisms like Proof of Work
(PoW) or Proof of Stake (PoS) to secure the network and prevent fraudulent activities.
Examples: Bitcoin and Ethereum are examples of public blockchains.
Private Blockchains
Private blockchains, also known as permissioned blockchains, are only accessible to a select
group of individuals or organizations. These blockchains are usually controlled by a single
entity or a consortium of entities.
Here are some key features of private blockchains:
Restricted Participation: Only authorized participants can join the network and
validate transactions.
Efficiency: Private blockchains are generally faster and more efficient than public
blockchains as they don’t require complex consensus mechanisms.
Privacy: Transactions are only visible to the participants in the network, ensuring
privacy and confidentiality.
Examples: Hyperledger Fabric and R3 Corda are examples of private blockchains.
Consortium Blockchains
Consortium blockchains are a hybrid of public and private blockchains. They are controlled
by a group of organizations rather than a single entity. Consortium blockchains are often used
in business collaborations where multiple parties need to interact and share data securely.
Here are some key features of consortium blockchains:
Shared Control: Control is shared among a consortium of organizations, reducing the
risk of a single point of failure.
Privacy and Transparency: Consortium blockchains offer a balance between privacy
and transparency. Transactions are only visible to the participants in the network, but
the consensus process is transparent and can be audited.
Efficiency: Like private blockchains, consortium blockchains are more efficient than
public blockchains as they don’t require intensive consensus mechanisms.
Examples: Quorum, a blockchain platform developed by J.P. Morgan, is an example of
a consortium blockchain.
And that’s a wrap on the types of blockchains! Understanding these types is crucial as they
each have their strengths and weaknesses and are suited to different applications. In the next
lesson, we’ll dive into the world of cryptocurrencies and explore how they leverage blockchain
technology. Keep up the great work!