A New Secret Handshake Scheme with MultiSymptom Intersection for Mobile Healthcare Social Networks Abstract   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 informationsharing for patients with multiple symptoms. To achieve multisymptom matching and crossdomain communications for patients in MHSNs, we propose a new Secret Handshake scheme with MultiSymptom intersection ( MSSH ), which is derived from a linearcomplexity 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 affiliationhiding 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.

MHCOOS: An OfflineOnline Certificateless Signature Scheme for MHealth Devices Current trends of mobile technology have seen a tremendous growth in its application in smart healthcare. This has resulted in the adoption and implementation of mobile health (mhealth) systems by providing health assistance to the aging population. Despite its advantageous benefits, its computational complexities cannot be overlooked. Mhealth devices are portable processing tiny equipment with limited computational capabilities thereby making them complex for the implementation of public key cryptosystems. In spite of this, an OfflineOnline signature scheme called the MHCOOS has been proposed to solve the difficulties in the computational ability. The scheme enjoys the following benefits by splitting the signing part into both offline and online phases. The offline phase performs heavy computations when a message is absent, whereas lighter computations are performed at the online stage when a message is present. Secondly, the online computations are extremely fast due to the already computed offline signature value and lighter pairings involved. Our performance analysis demonstrates how the proposed scheme outperforms other schemes. Finally, the hardness of the scheme is proven under the Bilinear Diffiexe2x80x93Hellman (BDH) and Computational Diffiexe2x80x93Hellman (CDH) problem in the random oracle model.