Axelar Network. What is it?

Axelar network provides a single cross-chain communication solution that satisfies the needs of both platform developers - no integration work required from them, and application developers - one simple protocol and API to access global liquidity and communicate with the entire ecosystem.

Axelar network consists of a decentralized network that integrates blockchain ecosystems that speak different languages ​​and a set of protocols with APIs on top of them, allowing applications to easily perform cross-chain requests. What makes it very popular in the current realities. The network connects existing autonomous blockchains such as Bitcoin, Stellar, Terra, Algorand and the Cosmos, Avalanche, Ethereum and Polkadot networks.

Project mission is to allow application developers to build such applications more easily using a generic protocol and API without deploying their own proprietary internet protocols or rewriting applications as new bridges emerge.
For this purpose, a set of protocols has been developed, which includes the Cross-Chain Gateway Protocol and the Cross-Chain Transfer Protocol.

Cross-Chain Gateway Protocol

Synchronization. Place information about the state of the source blockchain S into the state of the target blockchain D.
(For example, publishing the bitcoin block header on the Ethereum blockchain.)
Transfer of assets. Transfer a digital asset from S to D and vice versa.
(For example, transfer bitcoins from the Bitcoin blockchain to the Ethereum blockchain and then back to the Bitcoin blockchain.)

To keep things simple, chain D has at least minimal support for smart contracts, but S can be any blockchain.

Cross-Chain Transfer Protocol

CTP is an application layer protocol that allows applications to easily use cross-chain functionality. The integration is explained by the focus on asset transfer features (such as those used in DeFi). These applications usually consist of three main components: a graphical user interface, smart contracts on the same chain, and an intermediate node that publishes transactions between the interface and smart contracts. External interfaces interact with users' wallets to accept deposits, process withdrawals, etc. Applications can use cross-chain functionality by making CTP requests similar to HTTP/HTTPS GET/POST methods. These queries are subsequently accepted by the CGP layer for execution, and the results are returned to the users.

The main component of the network are the basic decentralized protocols. Validators collectively maintain the Axelar network and run the nodes that secure Axelar blockchain.
These validators are elected by users during the delegation process. They receive the right to vote in proportion to the share delegated to them. Validators reach consensus on the state of multiple blockchains to which the platform is connected. Blockchain is responsible for the support and operation of inter-network routing and transmission protocols.
Governance rules allow network participants to make protocol decisions, such as which blockchains to connect and which assets to support.

Axelar blockchain follows a Delegated Proof-of-Stake (DPoS) model similar to the Cosmos Hub. Users elect validators who must bind their stake in order to participate in the consensus and maintain a high quality of service. The DPoS model allows for the maintenance of a large set of decentralized validators and robust incentives to ensure that validators are held accountable for maintaining bridges and shares of cryptographic threshold schemes. As part of the consensus, validators run lightweight client software on other blockchains, allowing them to validate state.
other blockchains.

Validators report these states to Axelar blockchain, and once there are enough of them, the state of bitcoin, ethereum, and other chains is written to Axelar. Subsequently, the base layer of Axelar is aware of the state of external blockchains at any given time, creating “incoming bridges” from other blockchains.

Validators collectively maintain threshold signing accounts on other blockchains (for example, 80% of validators must approve and co-sign any transaction from it), which allows them to lock and unlock assets and state on different chains, as well as publish state on other blockchains, I mean outgoing bridges. In general, Axelar network can be considered as a decentralized read/write cross-chain oracle.