📄️ What's Chromia?
Why choose between a traditional database and a blockchain when you can have the best of both worlds? The _Relational Blockchain_ is a new architecture that combines the power and flexibility of mature database systems with blockchain's disruptive potential. Chromia is a relational blockchain platform for decentralized applications (dapps).
📄️ Chromia architecture
The integral relational database makes Chromia a full-stack decentralized development platform. This means that it includes all the layers necessary to build complete applications.
Providers are the backbone of the Chromia ecosystem. A provider is a person or organization responsible for nodes, which are physical or virtual instances of computing power.
A node is a machine that runs blockchains. Each node has its own PostgreSQL instance and runs the Postchain node process.
📄️ Decentralized application (dapp)
A dapp is an app that runs on a blockchain network. Its back end runs on nodes and could also have a front end on some client software.
📄️ Key pair
Chromia utilizes the power of public-key cryptography, a robust cryptographic system that employs a pair of keys: public keys and private keys, to establish secure and trustworthy transactions on the blockchain. These key pairs are generated using cryptographic algorithms and serve multiple purposes, such as authentication, encryption, and digital signatures.
📄️ System chains
Chromia is divided into multiple blockchains to achieve horizontal scalability. In this model, each node only needs to work with data related to its corresponding blockchains. This architecture increases scalability and simplifies updates, as an update of a single blockchain does not affect others. The overall system consists of several system blockchains, which are essential for Chromia functionality, and several dapp blockchains specific to particular applications.
📄️ Generic elements of the blockchain
You can visualize the structure of a Chromia blockchain with the help of the following diagram:
Our consensus method is based on PBFT (Practical Byzantine Fault Tolerance) protocol. It's our custom implementation from the ground up called eBFT, a Proof-of-Authority (PoA) protocol. In PoA, rights to generate new blocks are awarded to nodes that have proven their authority. These nodes are called validator nodes, and they validate transactions and blocks.
📄️ Cross-chain communication
Empowering seamless cross-chain communication is the Interchain Messaging Facility (ICMF), which is orchestrated by system providers and verified at the blockchain level. In parallel, the Interchain Confirmation Facility (ICCF) refines cross-cluster communication, enabling a single chain to validate transactions confirmed on another. ICMF finds its niche in internal network exchanges between utility chains, whereas ICCF caters to dapp developers, fostering agile cross-chain interactions. Together, these mechanisms ensure both efficiency and security in communication between dapp and system chains throughout the Chromia network. For more information, see the cross-chain overview section.
To encourage providers to secure their nodes, they must stake Chroma tokens representing the provider's stake in the Chromia economy. The stake is used as collateral and forfeited when the provider's nodes misbehave.