Patient privacy protection using anonymous access control techniques

Objective: The objective of this study is to develop a solution to preserve security and privacy in a healthcare environment where health-sensitive information will be accessed by many parties and stored in various distributed databases. The solution should maintain anonymous medical records and it should be able to link anonymous medical information in distributed databases into a single patient medical record with the patient identity. Methods: In this paper we present a protocol that can be used to authenticate and authorize patients to healthcare services without providing the patient identification. Healthcare service can identify the patient using separate temporary identities in each identification session and medical records are linked to these temporary identities. Temporary identities can be used to enable record linkage and reverse track real patient identity in critical medical situations. Results: The proposed protocol provides main security and privacy services such as user anonymity, message privacy, message confidentiality, user authentication, user authorization and message replay attacks. The medical environment validates the patient at the healthcare service as a real and registered patient for the medical services. Using the proposed protocol, the patient anonymous medical records at different healthcare services can be linked into one single report and it is possible to securely reverse track anonymous patient into the real identity. Conclusion: The protocol protects the patient privacy with a secure anonymous authentication to healthcare services and medical record registries according to the European and the UK legislations, where the patient real identity is not disclosed with the distributed patient medical records

HP-sequence design for lattice proteins - an exact enumeration study on diamond as well as square lattice

We present an exact enumeration algorithm for identifying the {\it native} configuration - a maximally compact self avoiding walk configuration that is also the minimum energy configuration for a given set of contact-energy schemes; the process is implicitly sequence-dependent. In particular, we show that the 25-step native configuration on a diamond lattice consists of two sheet-like structures and is the same for all the contact-energy schemes, ${(-1,0,0);(-7,-3,0); (-7,-3,-1); (-7,-3,1)}$; on a square lattice also, the 24-step native configuration is independent of the energy schemes considered. However, the designing sequence for the diamond lattice walk depends on the energy schemes used whereas that for the square lattice walk does not. We have calculated the temperature-dependent specific heat for these designed sequences and the four energy schemes using the exact density of states. These data show that the energy scheme $(-7,-3,-1)$ is preferable to the other three for both diamond and square lattice because the associated sequences give rise to a sharp low-temperature peak. We have also presented data for shorter (23-, 21- and 17-step) walks on a diamond lattice to show that this algorithm helps identify a unique minimum energy configuration by suitably taking care of the ground-state degeneracy. Interestingly, all these shorter target configurations also show sheet-like secondary structures.Comment: 19 pages, 7 figures (eps), 11 tables (latex files

Trust Model for Optimized Cloud Services

Cloud computing with its inherent advantages draws attention for business critical applications, but concurrently expects high level of trust in cloud service providers. Reputation-based trust is emerging as a good choice to model trust of cloud service providers based on available evidence. Many existing reputation based systems either ignore or give less importance to uncertainty linked with the evidence. In this paper, we propose an uncertainty model and define our approach to compute opinion for cloud service providers. Using subjective logic operators along with the computed opinion values, we propose mechanisms to calculate the reputation of cloud service providers. We evaluate and compare our proposed model with existing reputation models

Secure communication using dynamic VPN provisioning in an Inter-Cloud environment

Most of the current cloud computing platforms offer Infrastructure as a Service (IaaS) model, which aims to provision basic virtualised computing resources as on-demand and dynamic services. Nevertheless, a single cloud does not have limitless resources to offer to its users, hence the notion of an Inter-Cloud enviroment where a cloud can use the infrastructure resources of other clouds. However, there is no common framework in existence that allows the srevice owners to seamlessly provision even some basic services across multiple cloud service providers, albeit not due to any inherent incompatibility or proprietary nature of the foundation technologies on which these cloud platforms are built. In this paper we present a novel solution which aims to cover a gap in a subsection of this problem domain. Our solution offer a security architecture that enables service owners to provision a dynamic and service-oriented secure virtual private network on top of multiple cloud IaaS providers. It does this by leveraging the scalability, robustness and flexibility of peer- to-peer overlay techniques to eliminate the manual configuration, key management and peer churn problems encountered in setting up the secure communication channels dynamically, between different components of a typical service that is deployed on multiple clouds. We present the implementation details of our solution as well as experimental results carried out on two commercial clouds

Dynamic virtual private network provisioning from multiple cloud infrastructure service providers

The Cloud infrastructure service providers currently provision basic virtualized computing resources as on demand and dynamic services but there is no common framework in existence that allows the seamless provisioning of even these basic services across multiple cloud service providers, although this is not due to any inherent incompatibility or proprietary nature of the foundation technologies on which these cloud platforms are built. We present a solution idea which aims to provide a dynamic and service oriented provisioning of secure virtual private networks on top of multiple cloud infrastructure service providers. This solution leverages the benefits of peer to peer overlay networks, i.e., the flexibility and scalability to handle the churn of nodes joining and leaving the VPNs and can adapt the topology of the VPN as per the requirements of the applications utilizing its intercloud secure communication framework

R-PEKS: RBAC Enabled PEKS for Secure Access of Cloud Data

In the recent past, few works have been done by combining attribute-based access control with multi-user PEKS, i.e., public key encryption with keyword search. Such attribute enabled searchable encryption is most suitable for applications where the changing of privileges is done once in a while. However, to date, no efficient and secure scheme is available in the literature that is suitable for these applications where changing privileges are done frequently. In this paper our contributions are twofold. Firstly, we propose a new PEKS scheme for string search, which, unlike the previous constructions, is free from bi-linear mapping and is efficient by 97% compared to PEKS for string search proposed by Ray et.al in TrustCom 2017. Secondly, we introduce role based access control (RBAC) to multi-user PEKS, where an arbitrary group of users can search and access the encrypted files depending upon roles. We termed this integrated scheme as R-PEKS. The efficiency of R-PEKS over the PEKS scheme is up to 90%. We provide formal security proofs for the different components of R-PEKS and validate these schemes using a commercial dataset

Privacy-Preserving iVector-Based Speaker Verification

This paper introduces an efficient algorithm to develop a privacy-preserving voice verification based on iVector and linear discriminant analysis techniques. This research considers a scenario in which users enrol their voice biometric to access different services (i.e., banking). Once enrolment is completed, users can verify themselves using their voice print instead of alphanumeric passwords. Since a voice print is unique for everyone, storing it with a third-party server raises several privacy concerns. To address this challenge, this paper proposes a novel technique based on randomization to carry out voice authentication, which allows the user to enrol and verify their voice in the randomized domain. To achieve this, the iVector-based voice verification technique has been redesigned to work on the randomized domain. The proposed algorithm is validated using a well-known speech dataset. The proposed algorithm neither compromises the authentication accuracy nor adds additional complexity due to the randomization operations

Prevalence of Sleep Related Breathing Disorders and the Assessment of Quality of Sleep in Patients with Chronic Hypercapnic Respiratory Failure

BACKGROUND: COPD will be the third leading cause of death by year 2020. In India, COPD and Post TuberculousSequelae are very common chronic respiratory diseases that have significant morbidity and mortality.Sleep related symptoms occur in about 40% of cases in patients with COPD. Sleep related breathing disorders constitute the greatest number of disorders of sleep in patients treated by sleep medicine, pulmonary, and general practitioners in the outpatient setting. AIM OF THE STUDY : 1. To know the prevalence of sleep related breathing disorders (SRBD) in patients with Chronic Hypercapnic Respiratory Failure. 2. To assess the quality of sleep in patients with Chronic Hypercapnic Respiratory Failure. MATERIAL AND METHODS: Patients enrolled in the COPD registry at Government Hospital of Thoracic Medicine Tambaram,with severe stable COPD or COPD with Pulmonary Tuberculosis Sequelaeare evaluated. Spirometry is done for those patients. Patients with FEV1< 40% by spirometry are included, Arterial Blood Gas analysis is done. Those with Chronic Hypercapnic Respiratory Failure are included in the study. Patients with similar degree of obstruction without Respiratory Failure are used as comparison group. Overnight Polysomnography was performed in those patients. Epworths Sleepiness Score and Pittsburg sleep quality index scoring is done. Data is analyzed by standard statistical methods. RESULTS: Forty Five patients are enrolled into the study in total. Thirty two patients are Patients with Chronic Hypercapnic Respiratory Failure (Group A). Thirteen patients had COPD or COPD with Pulmonary Tuberculosis sequelae and with similar degrees of airflow obstruction without Respiratory failure (Group B).The mean Age group is 57.2 vs 57.8 years. Significant Nocturnal Desaturation is seen in 68.8% of patients with Group A and 38.5% of patients in Group B. Snoring is present in 41% of Group A and 23.07% of Group B. Obstructive Sleep apnea is seen in 2 patients in Group A (6.25%). Sleep latency (in minutes) is 62.7 vs 42.4. arousal index is 31.1/hour vs 20.4/ hour, NREM1, 2 (in Minutes) 208.1 vs 180.1, NREM3 (Min) is 20.7 vs 33.9, REM (min) 34.7 vs 48.6. In Group A, 68.8 % of patients have significant nocturnal desaturation vs 38.5% in Group B. Mean Epworth Sleepiness score is 11.5 vs 9.7, MeanPSQI score is 13.2vs 7.3. CONCLUSION: Nocturnal Desaturation is seen in significant proportion of patients with Chronic Hypercapnic Respiratory Failure (68.8%). There is good correlation between the Quality of sleep measurement by Pittsburgh Sleep Quality Index scoring and the sleep variables determined by polysomnography. Patients with Chronic Hypercapnic Respiratory Failure have decreased Total Sleep Time, Increased Sleep Latency, Decreased Sleep Efficiency, Decreased NREM Stage 3 Sleep, Decreased REM Sleep, Increased Arousal, Increase in duration of Wake after Sleep Onset when compared to normal values of that age. Based on these variables it is concluded that Sleep Quality in patients with Chronic Hypercapnic Respiratory Failure is poor. The prevalence of sleep related breathing disorders (SRBD) in patients with Chronic Hypercapnic Respiratory Failure is 6.25% which is similar to that general population