In this article, we intend to examine and evaluate various types of blockchain networks. Blockchains come in a wide range of functionalities and implementations. Nowadays, different types of blockchains have been created and introduced, each possessing diverse features in terms of network and their applications. Stay with us until the end to become more familiar with these networks. 

Currently, there are four basic types of blockchain protocols:

1. Public Blockchain

2. Private Blockchain

3. Hybrid Blockchain

4. Consortium Blockchain

Below, we introduce each type of blockchain and discuss their advantages and disadvantages.

Public Blockchain:

A public blockchain is permissionless, meaning it is entirely decentralized, and anyone can participate in it. This type allows anyone connected to the internet to access, download, and join as a valid node. All nodes within a public blockchain have equal rights to access and interact with the network. Public blockchains are often used for digital currency exchange and mining. The most common consensus algorithms used in public blockchains are Proof of Work and Proof of Stake.

Advantages:

. Freedom for everyone: Anyone can access the network.

. Pseudonymity: No need to disclose identity to participate.

. Decentralized: No central authority or entity controls the network.

. Transparency: Anyone can have full access to the ledger at any given time, reducing the chances of corruption or disputes.

. Immutable: Once blocks are created, it's practically impossible for anyone to alter or tamper with the blockchain.

. Incentives: Miners or validators can earn rewards for discovering new blocks or validating transactions.

Disadvantages:

.  Low TPS (Transactions Per Second): Public blockchains process transactions very slowly due to a large network with many nodes, which takes time to confirm transactions and perform proof of work.

. Scalability issues: Transactions in public blockchains are processed slowly, affecting scalability. As the network grows, its speed decreases, potentially becoming slow, congested, and expensive.

. High energy consumption: Proof of work mechanisms are energy-intensive, requiring significant amounts of energy. Efficient energy-saving methods are needed for this technology.

. Not suitable for sensitive or proprietary data: Public blockchains lack mechanisms to hide data from certain entities or individuals. For example, if a blockchain needs to record personal medical or financial information, it will be visible to everyone worldwide.

Use Cases of Public Blockchain:

. Voting: Governments can use a public blockchain for elections, ensuring openness and trust.

. Capital acquisition: Businesses or innovative projects can use a public blockchain to improve transparency and build trust.

Examples:

Bitcoin, Ethereum, Litecoin and Monero are famous examples of public blockchain.

Private Blockchain:

A private blockchain requires permission, meaning only certain individuals are allowed to participate. This type of blockchain is controlled by a company or organization, which determines who has access and permits reading and writing access for authorized users on the network. Private blockchains are similar to public blockchains in being peer-to-peer and decentralized but are much smaller in comparison.

Advantages:

. Speed: Transactions on private blockchains are faster due to fewer nodes, reducing the time needed to confirm a transaction.

. Scalability: Private blockchains can adjust their size according to a company's specific needs, making them scalable as companies can easily increase or decrease the size of their network.

. Privacy: These networks prioritize privacy, security, and confidentiality of all stored data.

. Security: Unlike public blockchains, private blockchains are more protected against illegal activities due to a rigorous identity verification process for participants.

Disadvantages:

. Less trust: In a private network, there are fewer participants compared to a public network, leading to less trust.

. Lower security: These networks have fewer nodes or members, making them more vulnerable to security threats.

. Not entirely decentralized: Private blockchains rely on a centralized system and third-party management systems.

Use Cases of Private Blockchain:

. Supply chain management: A private blockchain can be used for managing a company's supply chain.

. Asset ownership: It can be used for tracking and verifying assets.

. Internal voting: Internal elections can be conducted using a private blockchain.

Examples:

Ripple, Multichain and Hyperledger Fabric are famous examples of private blockchain.

Hybrid Blockchain

Organizations seeking the best features of both types of blockchains use a hybrid blockchain that combines the characteristics of both private and public blockchains.

In this case, companies can build a permissioned private system alongside a public and permissionless system. This way, they can choose who has access to specific blockchain data and which data should be publicly available.

In a hybrid blockchain, transactions and records are usually not public but can be validated through access permissions via a smart contract if necessary.

Additionally, members of a hybrid blockchain can decide who participates in the blockchain and which transactions are made public.

Advantages:

. Closed and Secure Ecosystem: This type of blockchain operates in a closed ecosystem, allowing private data to be stored and validated within the network but inaccessible from outside.

. Flexibility: Hybrid blockchain provides a flexible process to customize the ledger based on its and the network's needs.

. Better Scalability: Scalability of this blockchain can be superior to public blockchains, with transactions being cheaper as it utilizes multiple nodes for transaction confirmation.

Disadvantages:

. Lack of Transparency: Since information can be hidden, this type of blockchain is not entirely transparent.

. Lack of Incentives: Participants in this network do not receive rewards like miners in a public blockchain.

. Slow Upgrades: Upgrading and development can be a challenge for this network. It lacks the inherent incentive for widespread adoption.

Use Cases of Hybrid Blockchain

. Real Estate: Real estate companies can utilize hybrid networks for their systems and provide information for public use.

. Retail: Hybrid blockchains can assist retailers in simplifying their operations.

. Regulated Markets: Hybrid blockchains are suitable for regulated markets such as the banking sector.

Examples:

Food Trust, XinFin and Dragonchain are famous examples of hybrid blockchain.

Consortium Blockchain

A consortium blockchain, also known as a federated blockchain, is more decentralized than a private blockchain. Similar to a hybrid blockchain having both private and public blockchain features, a consortium blockchain differs in one aspect.

Unlike hybrid blockchains controlled by an authority, a consortium blockchain is designed by a group of multiple entities looking to use a decentralized network for collaboration. External users cannot access this blockchain network. In a consortium blockchain, predetermined nodes control consensus mechanisms.

The consortium has a validating node responsible for initiating, receiving, and validating transactions. Transactions can be initiated or received by member nodes.

Advantages:

. Security: A consortium blockchain is safer, more scalable, and efficient than a public blockchain. Like private and hybrid blockchains, it has access controls. Blockchain information is not publicly accessible. Only network participants can access the information.

. Control: This blockchain is not controlled by a central authority. Instead, a specific group of reputable network participants has control over the blockchain.

. Validation: In this blockchain, the number of participants is predetermined and validated. Identity verification is done to reduce data risks and privacy threats.

. Transaction Fee-Free: Unlike other blockchains, this network does not charge participants for services or transactions.

Disadvantages:

.  Lack of Transparency: A consortium blockchain has less transparency. If a member node infiltrates, it can still be hacked, making the network inoperable.

. Framework: This blockchain lacks the features of a cohesive framework and is vulnerable to malicious participants with its centralized network structure.

. Slow and Limited Upgrades: Upgrading protocols is often a dilemma in this network, especially as the number of participants increases.

Use Cases of Consortium Blockchain

. Banking and Payments: A consortium blockchain can be formed by a group of collaborating banks. They control which nodes validate transactions.

. Research Sector: A consortium blockchain can be used for sharing research data and results.

. Food Tracking: It's suitable for food tracking purposes.

Examples:

Quorum, Corda , Hyperledger, R3 are famous examples of Consortium Blockchain.

Conclusion

In this tutorial, you became familiar with the types of blockchains, their characteristics, and the pros and cons of different blockchain types. Each of these networks has its own specific advantages, and as a result, there is no simple answer to which blockchain to use. Everything depends on the needs of a business.