New Multiparty Signature Schemes for Network Routing Applications

Abstract

We construct two new multiparty digital signature schemes that allow multiple signers to sequentially and non-interactively produce a compact, fixed-length signature. First, we introduce a new primitive that we call ordered multisignature (OMS) scheme, which allows signers to attest to a common message as well as the order in which they signed. Our OMS construction substantially improves computational efficiency and scalability over any existing scheme with suitable functionality. Second, we design a new identity-based sequential aggregate signature scheme, where signers can attest to different messages and signature verification does not require knowledge of traditional public keys. The latter property permits savings on bandwidth and storage as compared to public-key solutions. In contrast to the only prior scheme to provide this functionality, ours offers improved security that does not rely on synchronized clocks or a trusted first signer. We provide formal security definitions and support the proposed schemes with security proofs under appropriate computational assumptions. We focus on applications of our schemes to secure network routing, but we believe that they will find other applications as well.