Learn More

What Are You Doing in This App?

In this interactive app, you're not just clicking buttons, you're engaging with real cryptographic operations. You've:

• Created real BLS private and public key pairs
• Signed a message using private keys
• Aggregated those signatures into one compact representation
• Verified the aggregated signature using bilinear pairings

This is the exact math Ethereum validators use every day in its proof-of-stake consensus layer — specifically using the BLS12-381 elliptic curve.

What Are BLS Signatures?

BLS stands for Boneh–Lynn–Shacham, the researchers who introduced this digital signature scheme. BLS signatures are based on elliptic curve cryptography and pairing-based math.

They're known for:

• Signature aggregation: Multiple signatures on the same message can be combined into one
• Compact size: Only 96 bytes per signature, no matter how many signers
• Efficient verification: Verifying one aggregated signature is much faster than verifying many individual ones

This is why Ethereum uses BLS signatures to aggregate thousands of validator signatures into one, reducing bandwidth and processing costs.

What Are Bilinear Pairings?

Bilinear pairings are special mathematical functions that act like a bridge between cryptographic groups. They take two inputs — each from a different group — and map them into a third group, in a way that preserves structure.

Properties:

• Bilinearity: Linear with respect to both inputs
• Non-degenerate: You don't get a trivial result (like always 1)
• Efficiently computable: The pairing must be usable in real time

In BLS signatures, pairings are used to check that a signature was created by a private key that corresponds to a given public key, without revealing the key itself.

Why Are BLS Signatures Important?

BLS signatures are critical for scaling blockchain infrastructure:

• ⚡ Ethereum consensus: BLS is the signature scheme used in Ethereum's Beacon Chain. Thousands of validators aggregate signatures to finalize blocks.
• 🧠 zkRollups & bridges: Use BLS to prove quorum-based decisions efficiently
• 📉 Bandwidth reduction: With BLS, you don't need to transmit 10,000 validator signatures, one will do

Their compactness and security make them a perfect fit for high-throughput, decentralized systems.