How to Build a parachain on Polkadot
Blockchain interoperability is essential for effective cooperation. However, many existing solutions that allow cross-blockchain communication can be complicated, overloaded and narrow. They also include a third party, and they are often not fully secure. However, there is one solution to some of these problems.
The Polkadot network has developed a protocol that allows blockchains to interact safely and securely. This protocol allows the creation of parachains or blockchains that can be connected to the main Polkadot network. It allows for the transmission of messages and transactions among chains, which provides shared security and enormous potential for scaling.
In this article, we will take a closer look at Polkadot and provide an example of how to build a parachain with substrate framework. The substrate is an open-source framework that allows developers to create highly customized blockchains. Substrate is ready to use right out of the box. It supports connecting to Polkadot or Kusama. This makes it an ideal framework to create parachains. Polkadot created the parachain model to facilitate the advancement of decentralized systems and web3 in general.
We will now explore parachains and how substrate can be used to create parachains in Polkadot.
What are Parachains?
Parachains are heterogeneous multichains that allow multiple chains to connect to one another through the Polkadot relay chain by obtaining a parachain slot. Parachains, which are Layer 1 blockchains that sit on top of Layer 0 relay chains, run in parallel.
Polkadot parachains can have native tokens, runtime logic and economies. Parachains also gain greater security by connecting to Polkadot’s relay chain. Besides, they get Polkadot’s benefits, such as interoperability and scalability, with other parachains.
Parachains can be used to deploy digital wallets, IoT apps and DeFi apps, as well as web3 infrastructure. Polkadot suggests developers use parachains on Polkadot in order to overcome difficulties like scalability and applicability present within siloed blockchains. Polkadot parachains can be public, private or hybrid blockchains.
The working mechanism of Polkadot architecture
The Polkadot network operates at two levels -Layer 0 and Layer 1. Layer 1 includes the parachains. Layer 0 is the main relay chain that runs all of the parachains. Collators are nodes that link a parachain to a relay chain. They are full nodes in the parachain that carry vital information.
Parachains may have their own tokens and requirements for implementation. They also define the incentivization process for the collator nodes. Polkadot’s interoperability allows parachains to communicate with each other, which keeps the main relay chain free from being clogged by every transaction. The relay chain is responsible for staking transactions, governance, and sharing security with the entire network.
Polkadot’s unique approach to crypto is the parachains are available for purchase by other crypto projects. Projects must win an online auction to secure these rare parachain slots. These auctions are usually held after parachains have been tested and deployed. These auctions use the DOT tokens as the bidding currency. A project can customize a parachain once they acquire it.
How to set up parachain?
Setting up parachain is a complex process for deploying your own blockchain. The following steps will help you build a parachain on substrate. Start by creating a runtime logic. The following substrate parachain template can be used for this purpose:
Step 1: Runtime logic
- Clone the parachain template: git clone https://github.com/substrate-developer-hub/substrate-parachain-template
- Switch into the parachain template directory: cd substrate-parachain-template
- Checkout the proper commit: git checkout polkadot-v0.9.30
- Build the parachain template collator: cargo build –release
- Check if the help page prints to ensure the node is built correctly: ./target/release/parachain-collator –help
Step 2: Build wasm executable
Next, compile the runtime logic to a wasm executable. The wasm code folder will contain all of the chain’s STF. This code blob is essential for deploying the project to parachain.
Step 3: Submit wasm code for validation
Next, submit your wasm code that Polkadot validators utilize to validate the STF of your chain.
Step 4: Bring the collator node into the picture
The Polkadot validator uses a collator to determine which STF is current. The collator node must be the maintainer for your parachain. It must produce new block candidates and pass them along to the validators in order to be included in Polkadot’s relay chain. Cumulus can be used to convert your substrate-constructed chain logic into a Polkadot-compatible parachain.
Substrate’s built-in networking layer does not support relay chains but only single ones. The Cumulus extension makes substrate’s chain logic compatible with Polkadot. This allows you to establish your blockchain in a parachain.
Step 5: Use Cumulus to convert your chain logic into a parachain
Substrate’s integrated networking layer only supports single chains. It does not support any chain connected to relay chains. This is where Cumulus extension can help. By converting your blockchain to a parathread or parachain, the Cumulus extension makes your substrate-built logic compatible with Polkadot.
Parachain testing
Polkadot’s Rococo testnet is used to test the parachain.
Rococo testnet
Rococo allows you to test your parachain and verify that messages are being transmitted and received between the parachain and the relay chain. Messages are sent first to the relay chain and then to the parachain. Rococo uses HRMP (Horizontal Relay-routed Message Passing) and Cumulus for the testing.
Next, run the following command to obtain ROC tokens-
! drip YOUR_ROCOCO_ADDRESS
Even though Rococo parachains share the same runtime code as their counterparts, the parachain IDs required to register with the relay chains will differ. Now compile the binary below to run a Rococo collator.
cargo build –release –locked -p polkadot-collator
The final step of the testing phase is to procure some ROC tokens at the Rococo Faucet. The following command can be used for this:
./target/release/polkadot-collator –chain $CHAIN –validator
Parachain deployment
After successfully testing your parachain for cross-chain transfer, you will need to deploy it on Polkadot. To do this, you will need a parachain slot. Substrate-based chains for address formats use SS58 encoding.
Obtain a slot
It is not easy to get a parachain slot as Polkadot only offers a limited number of unlocked slots per month. Connecting to the Polkadot network is important for the parachain slot to be filled. If the parachain wants to be included at every relay chain block, it must avail the slot.
Endnote
Parachains offer many benefits, including interoperability, scalability, and shared security. Polkadot, a rapidly evolving blockchain protocol, is being used by both startups and large enterprises to support blockchain development. So, if you want to build a parachain and test it, seeking professional help is the best way to do this. Consult an expert Polkadot blockchain development company to seal your deal and get the best Polkadot blockchain development services.