An Efficient and Secure Delegated Multi-authentication Protocol for Mobile Data Owners in Cloud

摘要

Due to plenty of cloud-based applications emerging and booming recently, data owners always store their data in cloud and share them to data consumers through cloud servers. For security equirements, data owners are often asked to provide authentication tags to the corresponding data. Data consumers obtain the authenticated data from the cloud and expect the computation on the authenticated data. However, it is impractical for the mobile data owners to be online all the time and provide the authenticated computing results according to various data consumers' request. To tackle this issue, we propose an efficient and secure delegated multi-authentication protocol for mobile data owners in cloud, which enables the mobile data owners to conditionally delegate signing right to specified cloud servers without exposing the secret signing keys. The cloud servers provide the authentication services when data owners are not available. The security is built on an identity-based multi-proxy signature (IBMPS) scheme, which depends on the cubic residue assumption, equaling to the factorization assumption. Furthermore, our protocol is efficient compared to the pairing based schemes and the overhead is almost independent of the number of cloud servers.