A certificateless aggregate signature scheme for healthcare wireless sensor network

Healthcare industry is one of the areas where wireless sensor network provides a lot of opportunities. Online data sharing in healthcare industry not only increases the efficiency but also reduces the time constraints. In the healthcare wireless sensor network, patient's report is available online for health professionals without any delay after patient's checkup. Data privacy becomes an important issue in healthcare industry due to direct involvement of personal health related data of patients. Modified data may become a serious cause of casualty for patient. Digital signature scheme is a technique of public key cryptography that is widely accepted in digital world to retain privacy and integrity. Certificateless public key cryptography was proposed to remove the complication of certificate management in public key cryptography as well as the key escrow problem inherited in identity based cryptography. An aggregate signature scheme is a many to one map which maps different signatures on different messages to a single signature. This feature is very beneficial in an environment which is constrained by limited bandwidth and low computational time/effort, such as wireless sensor network, vehicular ad-hoc network and Internet of things. Our proposed certificateless aggregate signature enjoys the goodness of both the concepts, certificateless and aggregate. We construct a certificateless aggregate signature scheme and prove the security of constructed scheme by using widely-accepted Random Oracle Model under the computationally hard Diffie-Hellman assumption. Random Oracle Model based security analysis proves that our proposed scheme is provably secure against existential forgery on adaptive chosen message and identity attacks under the hardness of computational Diffie-Hellman problem and achieves the required goals such as confidentiality, non-repudiation and integrity. We use batch verification technique for speedy verification of signatures. Since energy consumption for aggregate signature verification in our scheme is lesser than that in many of the related schemes, the proposed CL-AS scheme is compatible with the resource scanty nature of wireless sensor networks. Thus the proposed CL-AS scheme is efficient and suitable for green healthcare wireless sensor networks (HWSNs). (C) 2017 Elsevier Inc. All rights reserved.