In Polkadot, in order to receive a parachain slot, you must first acquire DOTs in order to participate in an auction to lease a parachain. Only when you win the auction (by outbidding other DOT whales) do you get entitled shared security by DOT validators of the Relay Chain.
As described in their blog post:
- There will be a finite number of parachain slots that will start low at genesis and increase over time.
- There will be unpermissioned, market-based leasing of slots. To ensure fairness in allocating >parachain slots we decided to use auctions. Anyone can participate; the auction format is a candle auction modified for blockchain with a retroactively determined random ending time.
- If someone (individuals or smart contract) wins an auction they don’t need anyone’s permission to deploy their parachain.
- Parachain slots will have a finite lifetime.
- A small number of slots will be reserved for a limited period of time for special “common good” parachains to be administered by the Web3 Foundation.
While shared security is meant to be more formalized in this on-chain mechanism in Polkadot, it’s no less convenient than it is to bootstrap your chain on Cosmos with the existing network of Cosmos Hub validators.
In the case of Cosmos, you could just ask validators in the Cosmos validator working group to validate your chain.
Also, should you guys need technical support building a SDK chain, just go here.