ID-based content extraction signature

A new ID-based Content Extraction Signatures(CES)scheme based on the batch signature was proposed.In our scheme,the signer only needs to sign the whole message.But other schemes have to sign each partition of primitive formation,so it improved the efficiency,And the dishonest Private Key Generator can not impersonate any user at any time.The proposed signature scheme can defend existential forgery on adaptively chosen message and ID attack in the random oracle model.