Digital Signature

A digital signature is cryptographic proof that a message or transaction was authorized by the holder of a specific private key, without ever exposing that key. The signer runs the private key and the transaction data through a signing algorithm; anyone can then verify the result against the matching public key to confirm authenticity, and any change to the signed data invalidates the signature. Bitcoin and Ethereum use ECDSA over the secp256k1 curve for account signatures; other designs use EdDSA for deterministic signing or BLS signatures, which can be aggregated so a network can verify thousands of signatures — such as validator attestations — as one compact operation. A tokenized domain's transfers and DNS updates are authorized the same way: a valid digital signature from the wallet holding the domain's NFT is what proves the owner approved the change.