What is Boneh–Lynn–Shacham (BLS) Signature?

A Boneh–Lynn–Shacham (BLS) signature is a cryptographic signature mechanism that allows a user to verify that a signer is legitimate. BLS signatures make use of a bilinear pairing for verification, and its elliptic curve group properties help defend against specific attack types such as index calculus attacks, thus allowing for shorter signatures than Full Domain Hash (FDH) signatures with a comparable level of security.