Authenticated cross-subnet communication

A system for cross-chain communication in a blockchain platform, comprising:

• one or more processors;
• and
• a memory comprising instructions stored thereon, which when executed by the one or more processors, causes the one or more processors to perform:
• accepting, at a first blockchain, a first transaction including a message and a message payload;
• validating, at the first blockchain, the message by signing the message using signature keys of one or more validators in a first set of validators of the first blockchain;
• generating an aggregate signature based on the signature keys of the one or more validators in the first set of validators;
• submitting a second transaction on to a second blockchain, the second transaction including the message and the aggregate signature;
• identifying, at the second blockchain, the one or more validators in the first set of validators based on the aggregate signature;
• verifying that a stake threshold percentage of the first set of validators are included in the aggregate signature by referencing a shared registry;
• and
• validating, at the second blockchain, the second transaction based on the verifying.

A non-transitory computer-readable storage medium comprising instructions stored thereon, which when executed by one or more processors, cause the one or more processors to perform operations for cross-chain communication in a blockchain platform, comprising:

• accepting, at a first blockchain, a first transaction including a message and a message payload;
• validating, at the first blockchain, the message by signing the message using signature keys of one or more validators in a first set of validators of the first blockchain;
• generating an aggregate signature based on the signature keys of the one or more validators in the first set of validators;
• submitting a second transaction on to a second blockchain, the second transaction including the message and the aggregate signature based on the message payload;
• accepting, at the second blockchain, the second transaction;
• identifying, at the second blockchain, the one or more validators in the first set of validators based on the aggregate signature;
• verifying that a stake threshold percentage of the first set of validators are included in the aggregate signature by referencing a shared registry;
• and
• validating the second transaction based on the verifying.