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To provide a search functionality for encrypted data, public key encryption with keyword search (PEKS) has been widely recognized. In actual usage, a PEKS scheme should be employed with a PKE scheme since PEKS itself does not support the decryption of data. Since a naive composition of a PEKS ciphertext and a PKE ciphertext does not provide CCA security, several attempts have been made to integrate PEKS and PKE in a joint CCA manner (PEKS/PKE for short). In this paper, we further extend these works by integrating secure-channel free PEKS (SCF-PEKS) and PKE, which we call SCF-PEKS/PKE, where no secure channel is required to send trapdoors. We give a formal security definition of SCF-PEKS/PKE in a joint CCA manner, and propose a generic construction of SCF-PEKS/PKE based on anonymous identity-based encryption, tag-based encryption, and one-time signature. We also strengthen the current consistency definition according to the secure-channel free property, and show that our construction is strongly consistent if the underlying IBE provides unrestricted strong collision-freeness which is defined in this paper. We also show that such an IBE scheme can be constructed by employing the Abdalla et al. transformations (TCC 2010/J. Cryptology 2018). Finally, as an application of SCF-PEKS/PKE, we strengthen the security of encrypted Electronic Medical Record (EMR) system proposed by Guo and Yau (J. Medical Sys. 2015).

Big data has become one of the most imperative technologies for collecting, handling and analysing enormous volumes of data in a high-performance environment. Enterprise healthcare organizations needs high compute power for the large volume of sensitive data, as well as large storage for storing both data and results, preferably in the cloud. However, security and privacy of patient data have become a critical issue that restricts many healthcare services from using cloud services to their optimal level. Therefore, this issue has limited healthcare organizations from migrating patient data to a cloud storage, because the cloud operators have chance to access sensitive data without the owner’s permission. This paper proposes an intelligent security system called Intelligent Framework for Healthcare Data Security (IFHDS). IFHDS enables to secure and process large-scale data using column-based approach with less impact on the performance of data processing. The intelligent framework intends masking personal data and to encrypt sensitive data only. The proposed IFHDS splits sensitive data into multiple parts according to sensitivity level, where each part is stored separately over distributed cloud storage. Splitting data based on sensitivity level prevents cloud provider to break complete record of data if succeeds to decrypt part of data. The experimental results confirm that the proposed system secure the sensitive patient data with an acceptable computation time compared to recent security approaches.

In recent years, many countries have been trying to integrate electronic health data managed by each hospital to offer more efficient healthcare services. Since health data contain sensitive information of patients, there have been much research that present privacy preserving mechanisms. However, existing studies either require a patient to perform various steps to secure the data or restrict the patient to exerting control over the data. In this paper, we propose patient-controlled attribute-based encryption, which enables a patient (a data owner) to control access to the health data and reduces the operational burden for the patient, simultaneously. With our method, the patient has powerful control capability of his/her own health data in that he/she has the final say on the access with time limitation. In addition, our scheme provides emergency medical services which allow the emergency staffs to access the health data without the patient's permission only in the case of emergencies. We prove that our scheme is secure under cryptographic assumptions and analyze its efficiency from the patient's perspective.

Preserving the privacy of electronic medical records (EMRs) is extremely important especially when medical systems adopt cloud services to store patients' electronic medical records. Considering both the privacy and the utilization of EMRs, some medical systems apply searchable encryption to encrypt EMRs and enable authorized users to search over these encrypted records. Since individuals would like to share their EMRs with multiple persons, how to design an efficient searchable encryption for sharable EMRs is still a very challenge work. In this paper, we propose a cost-efficient secure channel free searchable encryption (SCF-PEKS) scheme for sharable EMRs. Comparing with existing SCF-PEKS solutions, our scheme reduces the storage overhead and achieves better computation performance. Moreover, our scheme can guard against keyword guessing attack, which is neglected by most of the existing schemes. Finally, we implement both our scheme and a latest medical-based scheme to evaluate the performance. The evaluation results show that our scheme performs much better performance than the latest one for sharable EMRs.

Emergency care is basically concerned with the provision of pre-hospital and in-hospital medical and/or paramedical services and it typically involves a wide variety of interdependent and distributed activities that can be interconnected to form emergency care processes within and between Emergency Medical Service (EMS) agencies and hospitals. Hence, in developing an information system for emergency care processes, it is essential to support individual process activities and to satisfy collaboration and coordination needs by providing readily access to patient and operational information regardless of location and time. Filling this information gap by enabling the provision of the right information, to the right people, at the right time fosters new challenges, including the specification of a common information format, the interoperability among heterogeneous institutional information systems or the development of new, ubiquitous trans-institutional systems. This paper is concerned with the development of an integrated computer support to emergency care processes by evolving and cross-linking institutional healthcare systems. To this end, an integrated EMS cloud-based architecture has been developed that allows authorized users to access emergency case information in standardized document form, as proposed by the Integrating the Healthcare Enterprise (IHE) profile, uses the Organization for the Advancement of Structured Information Standards (OASIS) standard Emergency Data Exchange Language (EDXL) Hospital Availability Exchange (HAVE) for exchanging operational data with hospitals and incorporates an intelligent module that supports triaging and selecting the most appropriate ambulances and hospitals for each case.

Searchable encryption is an important cryptographic primitive that enables privacy-preserving keyword search on encrypted electronic medical records (EMRs) in cloud storage. Efficiency of such searchable encryption in a medical cloud storage system is very crucial as it involves client platforms such as smartphones or tablets that only have constrained computing power and resources. In this paper, we propose an efficient secure-channel free public key encryption with keyword search (SCF-PEKS) scheme that is proven secure in the standard model. We show that our SCF-PEKS scheme is not only secure against chosen keyword and ciphertext attacks (IND-SCF-CKCA), but also secure against keyword guessing attacks (IND-KGA). Furthermore, our proposed scheme is more efficient than other recent SCF-PEKS schemes in the literature.

With the development of electronic systems, privacy has become an important security issue in real-life. In medical systems, privacy of patients' electronic medical records (EMRs) must be fully protected. However, to combine the efficiency and privacy, privacy preserving index is introduced to preserve the privacy, where the EMR can be efficiently accessed by this patient or specific doctor. In the literature, Goh first proposed a secure index scheme with keyword search over encrypted data based on a well-known primitive, Bloom filter. In this paper, we propose a new privacy preserving index scheme, called position index (P-index), with keyword search over the encrypted data. The proposed index scheme is semantically secure against the adaptive chosen keyword attack, and it also provides flexible space, lower false positive rate, and search privacy. Moreover, it does not rely on pairing, a complicate computation, and thus can search over encrypted electronic medical records from the cloud server efficiently.

With the development of information technology and medical technology, medical information has been developed from traditional paper records into electronic medical records, which have now been widely applied. The new-style medical information exchange system "personal health records (PHR)" is gradually developed. PHR is a kind of health records maintained and recorded by individuals. An ideal personal health record could integrate personal medical information from different sources and provide complete and correct personal health and medical summary through the Internet or portable media under the requirements of security and privacy. A lot of personal health records are being utilized. The patient-centered PHR information exchange system allows the public autonomously maintain and manage personal health records. Such management is convenient for storing, accessing, and sharing personal medical records. With the emergence of Cloud computing, PHR service has been transferred to storing data into Cloud servers that the resources could be flexibly utilized and the operation cost can be reduced. Nevertheless, patients would face privacy problem when storing PHR data into Cloud. Besides, it requires a secure protection scheme to encrypt the medical records of each patient for storing PHR into Cloud server. In the encryption process, it would be a challenge to achieve accurately accessing to medical records and corresponding to flexibility and efficiency. A new PHR access control scheme under Cloud computing environments is proposed in this study. With Lagrange interpolation polynomial to establish a secure and effective PHR information access scheme, it allows to accurately access to PHR with security and is suitable for enormous multi-users. Moreover, this scheme also dynamically supports multi-users in Cloud computing environments with personal privacy and offers legal authorities to access to PHR. From security and effectiveness analyses, the proposed PHR access scheme in Cloud computing environments is proven flexible and secure and could effectively correspond to real-time appending and deleting user access authorization and appending and revising PHR records.

Consequently, application services rendering remote medical services and electronic health record (EHR) have become a hot topic and stimulating increased interest in studying this subject in recent years. Information and communication technologies have been applied to the medical services and healthcare area for a number of years to resolve problems in medical management. Sharing EHR information can provide professional medical programs with consultancy, evaluation, and tracing services can certainly improve accessibility to the public receiving medical services or medical information at remote sites. With the widespread use of EHR, building a secure EHR sharing environment has attracted a lot of attention in both healthcare industry and academic community. Cloud computing paradigm is one of the popular healthIT infrastructures for facilitating EHR sharing and EHR integration. In this paper, we propose an EHR sharing and integration system in healthcare clouds and analyze the arising security and privacy issues in access and management of EHRs.