Exploring LFSR-Based Encryption for DICOM Images

In this paper, we examine the application of linear feedback shift registers (LFSRs)-based stream ciphers for the encryption of digital imaging and communications in medicine (DICOM). DICOM is the de facto standard for generating images from a variety of medical technologies and communicating such images on different platforms. The meta information stored in these digital images is of privileged nature and their security is extremely critical, not only when the images are at rest but also in motion. Since DICOM was established in the early 1990s and with the proliferation of cloud-based technologies, interests in the study of security protocols for DICOM images have been on the increase. Encryption plays a significant role in these security protocols. Several encryption algorithms have been applied. Conventional linear feedback shift registers-based encryption is breakable, therefore, this paper addresses cascading LFSR-based encryption algorithms that ensure nonlinearity in the generated keystream. This encryption is more secure and typically less in computational cost. The results from use cases demonstrate suitability of the proposed cascading LFSR encryption.