BLS12-381
ActorId (32 bytes):
0x6b6e292c382945e80bf51af2ba7fe9f458dcff81ae6075c46f9095e1bbecdc37
BLS12-381 is the first Built-in Actor integrated into the Vara runtime. It provides an interface that enables validators to perform native runtime computations of BLS cryptography methods.
BLS cryptography facilitates efficient signature aggregation and verification at scale using Elliptic Curve cryptography. However, these operations are computationally intensive, and the Wasm VM used in Vara is not capable (without significant increase of minimal hardware requirements) of processing them quickly enough to fit within the single block time of Vara’s network (which is 3 seconds).
The BLS12-381 Built-in Actor addresses this issue. A program on the blockchain can send a message to this actor's address with the necessary arguments for a BLS method call. The validator then executes this in native mode off-chain, and subsequently returns the result to the originating program that initiated the request.
On-chain BLS Limitations
While technically possible, executing BLS methods on-chain is extremely resource-intensive:
- Block Space: It would occupy 30+ blocks on the Vara network.
- Complexity: Requires manual optimization by dividing the algorithm into equivalent parts.
- Costs: Results in significantly higher gas consumption.