A Multi-Group Signature Scheme for Local Broadcasting

By exchanging the information on the status and the surrounding environment between devices, devices can determine the optimal action. We focus on the construction of a digital signature scheme for local broadcast, which allows the devices with limited resources to securely transmit broadcast messages. A multi-group authentication scheme that enables a node to authenticate its membership in multi verifiers by the sum of the secret keys has been proposed for its use on devices with limited resources. This paper proposes a multi-group signature scheme by converting the multi-group authentication via the Fiat-Shamir transform. In the proposed scheme, a sender can sign a message by the secret keys which multiple certification authorities issue and the signature can validate the authenticity and integrity of the message to multiple verifiers. By comparing the proposed scheme with a code-based signature scheme, where a sender signs a message by individual secret key as many times as the number of the secret key and each of verifiers verify each signature, the proposed scheme provides efficient multi-group signature in terms of the amount of transmitted data.