Address-Based Signature

摘要

In most applications using digital signatures, public keys are used to verify the signatures. The public keys are authenticated by a trusted certificate authority. However, this chain of trust is fragile in the real world. Systems like blockchain and eXpressive Internet Architecture (XIA) proposed to use the hash of a public key as an address. Then signatures are verified against addresses. In this paper, we first formalize the notion of address-based signatures to analyze the security of these address-based systems. We give a strong model which considers the security of multiple addresses, with respect to attackers who even know the randomness used by the system developers. The formalization of security model is important to understand the security of real world system. We propose an efficient and secure construction of address-based signature, which can overcome the existing problems of address-based ECDSA and Schnorr signatures. Then we give two generic constructions of address-based signatures. We find out that these solutions are either not efficient enough (in terms of signature size and address size) or not secure enough.