Type 1 pairing + CDH ⇒ Multi-signatures with proofs of possession
Statement
RY07 define a registered-key model that covers both the knowledge-of-secret-key assumption and key registration with a proof of possession (POP). In it, Boldyreva’s multisignature over a symmetric pairing group in which CDH is hard, with each public key registered under a simple POP, is unforgeable in the random oracle model (POP model) — RY07.
Notes
- Simple POPs also give security for the multisignature of Lu, Ostrovsky, Sahai, Shacham and Waters and for a two-user ring signature of Bender, Katz and Morselli — RY07.
- Boldyreva’s scheme was first proved secure under the stronger requirement that each key be registered with its secret key (Type 1 pairing + CDH ⇒ Multi-signatures in the KOSK model) — Bol03.