ID-based group-oriented proxy signature and blind signature from pairings

Multi-proxy signature and blind multisignature are two important group-oriented signatures. Multi-proxy signature allows the original signer delegate his signing power to a group of proxy signers. Blind multisignature allows the user to obtain a signature of a message from several signers in a way that each signer learns neither the message nor the resulting signature. Plenty of multi-proxy signature and blind multisignature schemes have been proposed under the Certificate-based (CA-based) public key systems. In this paper, we first propose an Identity-based (ID-based) multi-proxy signature scheme and an ID-based blind multisignature scheme from bilinear pairings. Moreover, we prove that the proposed schemes achieve the desired security notions.