Exploring the Multilateral Security Model of Cosmos Hub to Advance New Strategies for Blockchain Security

Recently, the product lead of Cosmos Hub at Informal Systems initiated a discussion on the consumer chain onboarding mechanism at the Cosmos Hub forum. In the context of fierce competition for inter-chain security solutions, Cosmos Hub is considering accelerating its layout in this area through consumer chains.

Previously, Cosmos Hub introduced the "shared security" mechanism through the V9 Lambda upgrade, allowing it to lease security to consumer chains while enhancing the value capture capability of ATOM. Shared security requires each validator of Cosmos Hub to run every consumer chain, ensuring that the consumer chains have the same level of security as Cosmos Hub. However, this method limits the use of consumer chains, increases the costs for validators, and is not suitable for low-cost consumer chains.

To this end, the product lead proposed two new consumer chain onboarding solutions:

1. Permissionless solution based on transactions:

   • Developers can initiate a consumer chain by submitting a transaction to the Cosmos Hub.
   • Validators choose whether to join the new Blockchain.
   • The security of the blockchain improves as the number of validators increases.
   • The advantage is that it is simple and open, while the disadvantage is that it requires developers to actively communicate with validators.

2. Selectively join the program through proposals (lightweight permission):

   • Developers need to submit governance proposals to launch a new Blockchain.
   • Validators decide whether to join through voting
   • After the vote passes, supporters automatically become a part of the new Blockchain.
   • The advantage is the use of existing governance mechanisms, while the disadvantage is the presence of certain technical barriers.

In addition, there is a "Top-N" scheme being discussed, which requires that the top n% of validators must run a consumer chain, while other validators can choose to join or exit.

In addition to replicated security, these new solutions allow the use of only a subset of the Cosmos Hub validator set, theoretically lower in security than replicated security, but each has its own characteristics.

As early as May 2023, the product manager compared three main inter-chain security solutions: replication security, selective joining security, and mesh security. Replication security offers the strongest security guarantees but has performance and cost issues; selective joining security is more flexible but faces challenges with security fluctuations; mesh security allows for bidirectional enhancement of security across chains and is a popular model recently.

In the future, Cosmos Hub may adopt a diversified security strategy, including replication security, permissionless joining, lightweight permissions, and Top-N solutions, to meet various security needs and provide more value capture opportunities for ATOM. This diversified security model will help Cosmos Hub maintain an advantage in the highly competitive Blockchain security field.