# Privacy-Aware Cloud Architecture for Collaborative Use of Patients' Health Information
## 3 Proposed Architecture  
Considering the complexity of the existing healthcare structure, where patients' health information is distributed to multiple entities such as hospitals, healthcare centers, and cloud servers, a centralized architectural design of information systems for the healthcare domain would not be suitable, especially when interoperability remains a challenging obstacle among the vast majority of healthcare information systems. A non-centralized architectural design would be the most suitable option for the healthcare sector so that disparate entities can collaborate through sharing information related to patients and their health.  
In this work, a new cloud-based architecture is proposed for storing and sharing healthcare information in a privacy-preserving manner. There are two sources of information that informed the design of the proposed cloud architecture: case study findings and a literature review [58]. The characteristics of the proposed cloud architecture are the following:  
* **Just-enough information disclosure**: disclosing only the right information according to the context in which it is required.
* **Accessible location of information**: Storing patients' information in one place for easy access whenever information is required.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Reference** & **Approach** & **Purpose** & **Challenges Highlighted** \\ \hline
[42; 43; 44; 45] & UML Profile for Messaging Patterns & Facilitate communication among systems & Healthcare information systems complexity \\
[47; 48; 49] & Enterprise Service Bus (ESB) & Applications integration to facilitate communications & Fragmentation of patients’ information in heterogeneous proprietary systems \\  & A survey of the state-of-the-art schemes on secure and privacy-preserving medical data sharing of the past decade with a focus on blockchain-based approaches. & Analyze advantages and disadvantages of blockchain privacy-preserving medical data sharing. & Query efficiency, scalability, and Information management and security. \\  & A mixed-method study using a questionnaire, in-depth interviews, and usability evaluation. & Introducing a novel blockchain-applied personal health records (PHR) application and validate its user experience. & Users trust in terms of the security of their information when shared using Blockchain. \\  & Blockchain approach that separates medical data processing, access control, and data sharing into local and blockchain networks. & Sharing data among different local blockchain networks (different institutions). & Quality of Service and Information privacy \\  & Proposed blockchain-based ABE scheme with multi-Authority for medical on demand in telemedicine system. & To achieve dynamic authentication and authorization with higher flexibility and efficiency. & Privacy and unauthorized access from insiders due to centralization. \\  & Evaluating the development of blockchain in healthcare from secure sharing of healthcare data. & Isques related to low throughput and low scalability, which limit its adoption in the healthcare industry \\  & & &  
* **Unified platform**: Accessing information through a unified platform is a key characteristic for improving healthcare services.
* **Adherence to the legal privacy-related frameworks**: The architecture should adhere to privacy-related regulations and policies such as HIPPA and the Information Privacy Act when using information.
* **Patients control**: Patients should have a means of controlling who can access their information.
* **Cloud provider blindness**: The cloud provider should not be able to read or access patients' information that is stored on the cloud.