Encrypted Domain Secret Medical-Image Sharing With Secure Outsourcing Computation in IoT Environment

In existing secret medical-image sharing (SMIS) schemes, to protect and manage secret medical-images (SMIs), the sharing and recovery of each SMI are implemented by local servers of medical institutions. However, since a lot of SMIs are produced by personal smart terminal devices in Internet of Things (IoT) environment, directly implementing the sharing and recovery processes will cause excessive communication and computing burden for those local servers, which makes the existing SMIS schemes not suitable for IoT environment. To address the above issue, we propose an encrypted domain SMIS (Enc-SMIS) scheme with secure outsourcing computation for protecting and managing medical images in IoT environment. In the proposed scheme, the medical images are first encrypted using fully homomorphic encryption (FHE) and then outsourced to a cloud server for generating a set of image shares. Subsequently, these shares are stored separately in different local servers of medical institutions. Furthermore, the recovery process is also outsourced to the cloud server when doctors need to observe the patients’ medical images. Compared with the existing SMIS schemes, the proposed Enc-SMIS scheme alleviates the computing and communication burden on local servers significantly with secure outsourcing computation in the semi-honest model, and thus supports the storage and management of medical images well in IoT environment.

I. Introduction

With the rapid development of smart terminal devices and Internet of Things (IoT) technologies, it has become increasingly convenient for people to continuously capture their medical records for monitoring their health or transmitting them to healthcare medical institutions. For example, smart bracelets are used to monitor heartbeat and blood pressure, smartphones are employed to count the sleep time of users, and some other devices are utilized to record people’s daily diet and exercise habits. The terminal devices generate and transmit a huge amount of medical data on networks every day. However, how to protect and manage these medical data effectively in IoT environment has become a challenge.