A New Secret Handshake Scheme with Multi-Symptom Intersection for Mobile Healthcare Social Networks

With the aggravating trend of aging population in modern societies, Mobile Healthcare Social Network (MHSN) is an attracting platform for improving the life quality of elderly patients and offering mutual supports. In a sustainable MHSN system, one essential issue is to protect sensitive healthcare information while providing information-sharing for patients with multiple symptoms. To achieve multi-symptom matching and cross-domain communications for patients in MHSNs, we propose a new Secret Handshake scheme with Multi-Symptom intersection (MSSH), which is derived from a linear-complexity Authorized Private Set Intersection (APSI) based on Schnorr signature. In MSSH, two anonymous patients, who have registered with independent healthcare centers, are able to successfully execute an affiliation-hiding mutual anonymous authentication only if their target authentication policies are satisfied. The authentication policy demands that the designated healthcare center should be matched and the cardinality of their symptoms intersection is not less than a threshold value. Meanwhile, the symptoms outside of the set intersection remain confidential. The formal analysis proves MSSH is secure under the Random Oracle Model (ROM). The experimental results demonstrate that MSSH is efficient and feasible in MHSNs.