Blockchain is a distributed database suitable for developing decentralized applications where data is being broadcasted to all the trustless entities which are part of the system. Blockchain technology has commendable features, and a feature like data broadcasting is immutable. It also maintains a single ledger for all the transactions which have ever happened. Maintaining a history of transactions helps to determine the state of the system, just by fetching them at any moment of time.
All the transactions are arranged by time and current state of the system. Integrity of the transactions, supported by implicit transaction authorization is a feature provided by the platform.
The Blockchain system consists of nodes which are also called Blockchain clients. Every node in the system is self-sufficient to perform the transactions, which is a main feature of decentralized applications. In such scenarios, if one node goes down, others are ready to serve the request so no single point of failure situation arises.
For the node to be part of a Blockchain network, the node must have Blockchain platform implementation to interact with other nodes in the system. Valid transactions are included in logical data structure known as a block. All the transactions are added in a chain of blocks where every block contains the address of its previous block.
Blockchain uses a decision making mechanism called consensus which decides eligibility to join the network as well as creation of the block.
Needless to say, the Blockchain network is secured by using implicit encryption mechanism as well as the consensus mechanism. Mainly, there are 2 consensus processes – Proof-of-Work and Proof-of-Stake.
An illustration of the Blockchain system network is given below:
Mainly, there are the following types of topologies possible to form the Blockchain network:
- Blockchain Public Network
- Blockchain Private Network
- Blockchain Consortium Network
1. Blockchain Public Network
In the Blockchain Public Network, there are no restrictions on reading Blockchain data and submitting transactions. That’s the reason why it is also called as permission-less network. Any external entity wishing to participate (also having Blockchain platform implementation) can join the Blockchain network and perform the transactions.
Participation in public Blockchain requires cryptographic puzzles to be solved which saps a huge amount of energy and needs very high-end system configuration. Also, there are no restrictions on the number of entities which can participate in the network. Public Blockchain network can be considered as ‘fully decentralized’ Blockchain networks since every entity who has equal rights to participate in a network, can work independently.
Currently, the following platforms are available to implement the public Blockchain network :
Ethereum is one of the most popular open source Blockchain platform to implement public Blockchain. The platform enables one to leverage capabilities of Ethereum Geth implementation by means of transactions and Smart Contracts. Smart Contract is a group of instructions to be executed to perform a certain task. It may consist of business rules and terms and conditions to be adhered to by entities to execute the transactions.
Currently, Ethereum abides by the Proof-of-Work consensus mechanism to validate the transactions as well as entities which wish to be part of a network. Bitcoin is a payment network deal with cryptocurrency, based on the Ethereum platform. POW consensus mechanism is by default provided by Ethereum, and is used by bitcoin network to authenticate the transactions. Fatcom is another example of a public Blockchain network provider for business process and data management.
BlockApps is a proprietary Ethereum-based Blockchain framework. It uses RestFul services interface to enable users to inteact with the BlockApps Ethereum platform.
2. Blockchain Private Network
In Blockchain, the Private Network owner reserves the rights to provide access to the network. Also, read-and-write access to the entities has to be provided on demand. Unlike Blockchain Public Network, Private Blockchain system is placed behind the firewall. Here, the network owner can also be termed as a Central Authority who is responsible for making changes to the network.
Private Blockchain is suitable for building proprietary systems like financial institutions’ back office operations, settlement and clearing services. Blockstream-created private network, called as Liquid is handled by federation and prospects need to get access rights from the federation to join the network.
Hyperledger supports private (permissioned) Blockchain through its identity management service which authenticates all participants in the network. Identity manager is also used for user authorization to provide role-based access to the services. Privacy and confidentiality can be maintained for individual users where the transaction between sets of users cannot be visible or accessible to other users of the network.
Multichain is another private Blockchain platform which supports user authentication and authorization. Easy network creation, rapid deployment and multiple database support are key features of the platform.
3. Blockchain Consortium Network
Blockchain Consortium Network is a hybrid approach driven by pre-identified entities who come to a common consensus to interact with each other. This is another form of private Blockchain network where read-write access is provided to certain number of people or nodes. Unlike the private Blockchain network, here, the ownership is divided between entities.
Blockchain – The Way Ahead
Blockchain platforms and related frameworks are still evolving and only a handful of organizations have adopted the idea and done the implementation. Private Blockchain concept is scaling up fast and organizations working on this concept are expected to grow multi-fold in a couple of years.
The following set of companies are using public Blockchain:
This number is expected to grow in the near future.