Hey everyone, welcome back to the course. Up till now, we have talked about how blockchain works. And we have also seen different kinds of platforms and consensus algorithms. All these platforms and consensus algorithms in the end fit into the blockchain architecture. Now, let's go and understand a typical blockchain architecture. What kind of different layers are required for the blockchain architecture, and how we can create our own architecture related to the same.

This is a general view of a blockchain architecture. As you can see, in this architecture diagram, we have defined five different layers. The bottom layer is described as a data layer, which holds all the information about the blocks, data and cryptography. This layer includes the data blocks, transactions, Merkle tree hash functions, Chain structures and cryptographic protocols. This layer will also define all the blockchain parameters required for the network. The second layer shown in blue is the network layer.

The network layer defines the functionalities which are required for the networking of the blockchain network layer defines how the nodes are going to connect the handshaking process between the nodes and the validations nodes will perform to authenticate the other nodes. In whole network layer includes the protocols and functionalities defining peer to peer and relay network systems. The third layer shown in green is the consensus layer. consensus layer is the one which makes sure that the data is validated, and immutably stored on top of the blockchain. The nodes inside the blockchain network provide a vote over the transaction or block data. And if the total number of votes is greater than two by three of the total participants, then the consensus is achieved and data is securely stored over the network, where nobody can modify it.

The consensus layer holds consensus algorithms and consulting definitions. Different consensus algorithms may be used within the consensus layer, including proof of work, proof of stake, delegated proof of stake or some other implementation of Byzantine fault tolerance. After the consensus layer, we have insensitive layer displayed in red. As the name suggests, the insensitive layer does not affect the blockchain architecture. Even if the insensitive layer is removed from the architecture, the blockchain will function smoothly. As you can see in the image insensitive layer is only holding the block rewards and the transaction increase.

If we remove the reward distribution and the transaction fees from the blockchain network, it won't affect the blockchain as such. The last layer shown in dark blue is the application layer. The application layer is at the top of the architecture as it allows users to connect with the blockchain. The end users will use the client side applications for interacting with the blockchain application layer holds both the tools demonstrating the working of the blockchain as well as user applications performing specified use cases. Different kinds of services can also be part of this layer. services like a virtual machine.

Decentralized applications, explorers or smart contracts will also be available in this layer, which could help in engaging with the front end and blockchain systems. The image shown here is another view for the blockchain archive In this image, you can see different types of layered architecture. The public layer is shown in red, the enterprise layer is displayed in violet color, and the application layer can be observed in orange color. At the bottom, we have a network model, which is holding protocols like peer to peer for the public layer, and enterprise peer to peer for enterprise layer. The model above the network is the core blockchain. As we have mentioned, there is no concrete architecture for the complete blockchain systems.

You can define your own architecture, the first architecture diagram, which we had shown you had the core blockchain at the bottom and the network layer above it. But in this diagram, we are keeping the network model on the bottom and the core blockchain above it. The core blockchain consists of specifications like on chain or off chain storage, synchronization options. Virtual Machine capabilities for computing the smart contracts, public or private consensus mechanisms, Trusted Execution processes, and all the other entities required to store the data and execution with provisioning of consensus. The core blockchain model will be different for public and enterprise layers, which can be seen in the image. After the core blockchain we have a privacy and scaling model.

Within the privacy and scaling, we can find the computation algorithms and processes required for the security and scaling of the blockchain network. In this model, we may also have wallets and private transactions for the enterprise layer, which can be modeled accordingly for better scaling. We can also define the capabilities and computation requirements for on chain and off chain storage, which will give us a much better view of the privacy and scaling required for the network. The Privacy and scaling model is then linked with the tooling model. The tooling model consists of the interfaces as well as the integration and Deployment Services. The tools required for the public layer may be different from the enterprise layer.

The public layer may include tools like key management, interchange, utilities, and wallets for handling user credentials. It may also define the API protocols required for the public blockchain to interact with the user applications. The Enterprise layer tools might include hardware security modules, and some other Identity Management Services, which can provide permission and authentication for the users. For example, in hyper ledger, we have a membership service provider, which acts as an Identity Manager and work similarly like active directories for the integration and deployment tools. We might have integration libraries or software development kits available. For example, Bitcoin and aetherium use JSON RPC commands for integrating user application.

Moreover, aetherium also provides web three JS library, which helps us in incorporating the blockchain to the applications. Enterprise layer need not to be open for all. That's why it might use enterprise management tools to integrate with applications. Enterprise layer may also include Oracle's which provide external data into the blockchain. final model in our architecture is the application model. The application model is mostly the same for both the public and the enterprise layers.

Whenever we are working with any technology, we need to have a client based application available, which will be used by users to interact with the technology in our application model. Apart from the decentralized front end applications, we might also have explorers and monitoring tools which helps in analyzing and auditing the blockchain networks. Examples of front end applications could be health record storage, or land record storage, these applications will utilize the capabilities of the blockchain. Apart from that, we can also keep smart contracts and standards required for the smart contracts. Governments and enterprises can define compliances and standards for the applications and smart contracts. For example, in aetherium blockchain we have token standards like ERC 20 or ERC seven to one.

These standards provide different functions and capabilities for different use cases. Finally, we can also keep programming languages required to develop smart contracts and decentralized applications as well as Formal verification processes to safeguard the data storage and sharing that goes about the blockchain architecture and how different architectures are available for the blockchain. The architectures explained here are the internal blockchain architectures, we are soon going to come up with another course related to explicitly to blockchain architecture and design patterns, which will give you much more in depth knowledge about how block chains can be integrated with enterprises and legacy systems if you have any queries and if you want to learn more about the upcoming courses, feel free to contact us at info at the rate v two blocks.com