Register & reserve a parachain

Every parachain must reserve a unique identifier—the ParaID—that enables it to connect to its specific relay chain. Each relay chain manages its own set of unique identifiers for the parachains that connect to it. The identifier is referred to as a ParaID because the same identifier can be used to identify a slot occupied by a parachain or to identify a slot occupied by a parathread.

You should note that you must have an account with sufficient funds to reserve a slot on a relay chain. You can determine the number of tokens a specific relay chain requires by checking the ParaDeposit configuration in the paras_registrar pallet for that relay chain. For example, Paseo Testnet requires 5 PASEO to reserve an identifier:

parameter_types! {
	pub const ParaDeposit: Balance = 5 * DOLLARS;
	pub const DataDepositPerByte: Balance = deposit(0, 1);
}

impl paras_registrar::Config for Runtime {
	type RuntimeEvent = RuntimeEvent;
	type RuntimeOrigin = RuntimeOrigin;
	type Currency = Balances;
	type OnSwap = (Crowdloan, Slots);
	type ParaDeposit = ParaDeposit;
	type DataDepositPerByte = DataDepositPerByte;
	type WeightInfo = weights::runtime_common_paras_registrar::WeightInfo<Runtime>;
}