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Bybit Learn
Jul 7, 2022

Relay Chain

The Relay Chain acts as the central chain for the Polkadot network. Polkadot is considered to be a heterogeneous multi chain that consists of shared interoperability and security.

The Polkadot network is a blockchain and cryptocurrency that facilitates interoperability between different blockchains. The Relay Chain is the core component that makes up the Polkadot network. The following guide offers a detailed overview of the Relay Chain and what it means to the crypto industry.

What Is a Relay Chain?

The Relay Chain serves as the central chain for Polkadot. Every validator with Polkadot is staked directly on the Relay Chain with the Polkadot cryptocurrency, known as DOT. Keep in mind that this chain comprises a relatively low number of different types of transactions, which include methods for taking part in NPoS, parachain auctions and the platform's governance mechanisms.

The Relay Chain is designed to have only a minimal amount of functionality. In fact, it doesn't support smart contracts. The purpose of the Relay Chain is to make sure that every component in the system is coordinating properly, which includes parachains. In most cases, the less general tasks are given to the parachains.

How Does a Relay Chain Work?

The Relay Chain participates in a large number of functions to ensure that the Polkadot network is running according to plan. The parachains that are connected to this chain facilitate stronger security within the Relay Chain itself. In the event that the Relay Chain reverts for some reason, every parachain responds by reverting as well, which allows the whole system to remain valid, and avoids issues where only one part is corrupted.

Keep in mind that the Relay Chain is backed by a considerable amount of stake, which means that the increased security of this stake also applies to the parachains connected to the Relay Chain.

In terms of interoperability, XCM is a format within Polkadot that accommodates messages created across different consensus mechanisms. With this format in place, parachains are able to directly communicate with each other.

This system also consists of blockchain bridges that allow data to be transferred across networks. While these chains are always interoperable, they can also be used as standalone chains with different rules, governance mechanisms and protocols. The Relay Chain connects to every bridge in the Polkadot network.

Relay Chain Specifics

The primary actors involved with the Relay Chain include validators, nominators and collators. Validators are tasked with producing blocks via the Relay Chain. These individuals also accept proof of stake transitions from the collators. Once these actions are performed, validators are given staking rewards.

Nominators aim to bond the stake they have to specific validators for the purpose of eventually getting into the validator set and producing Relay Chain blocks. In most cases, nominators are given a smaller portion of any staking rewards that the specific validator obtains.

As for collators, they are entire nodes on both the Relay Chain and a parachain. These nodes create state transition proofs and collect all parachain transactions. The transition proofs are then sent to the Relay Chain validators.

It's important to understand that Polkadot supports numerous execution slots, which act as scores via a CPU. Every execution slot is able to run a single process at a given time. These slots are maintained with parathreads and parachains, both of which are subscription models. While parachains run constantly, parathreads only run when they’re called on, and will share slots among groups of parathreads. The Relay Chain backs these processes up and ensures that they remain secure.

Why Is a Relay Chain Needed In the Polkadot Network?

The Relay Chain is the very core of the Polkadot network, and is directly responsible for maintaining the network's consensus mechanism, cross-chain interoperability and shared security. Because of how this chain is designed, every parachain in the network is able to benefit from the same characteristics that the Relay Chain has because of how all of these components are connected.

Now that you have a better idea of what the Relay Chain is and how it works with Polkadot, you can make more informed decisions with your current DOT holdings.