# Evaluation of a New-Concept Secure File Server Solution
## 2 Background  
### Review of File System-Related Security Solutions and Research  
The consequence of ransomware attacks, as described in the introduction, is mainly the loss of data availability. The evolution of protection techniques follows the evolution of ransomware, and the aim has always been to provide file systems with effective protection,which prevents the restriction of file accessibility during an attack. In the early days (\(\sim\)2006), the primary solution was to restore the file system as a process. The file system restoration (FSR) recovery method enables users to go back to a previous state of the file system. In their study, [PERSON] et al. [PERSON] et al. (2017) introduced a virtual disk environment (VDE) for undoing data changes on storages and restoring the undamaged files. VDE offers an effective restoring solution to a previous file system state, even in case of a system crash or a boot failure. VDE is similar to virtual disks used in virtualized infrastructures; however, they can be mounted without any hypervisor. Based on their implementation, the authors have analyzed the speed and the system load metrics of the VDE and concluded that, compared to the FSR-based solutions, the overhead is less. At the same time, recovery occurs quicker [PERSON] et al. (2017). Dealing with early solutions, [PERSON] et al. [PERSON] et al. (2018) found that the financial burden connected to losing data and their inaccessibility might be huge, and for this reason, companies apply different data protection solutions, like snapshotting, systematic backups, and maintaining remote mirrors, to protect their data integrity. The authors also found that choosing the proper combination of such strategies can be complicated since there are many different methods for keeping data safe and for resource management. Furthermore, during the design of storage systems, it often happens that the mixture of the applied technologies leads to oversized or undersized, often costly, inappropriate solutions. In addition, the authors have presented a theoretical, automated approach to designing reliable storage systems ([PERSON] et al., 2018). [PERSON] and colleagues [PERSON] and colleagues [PERSON] and colleagues (2018) worked on a similar mechanism to counteract the harmful effects of ransomware attacks. In their research, they investigated the problem of malicious modification of digital objects. As a result, they presented a protection mechanism to protect digital objects against unauthorized replacement or modification while allowing for authorized updates transparently. In their presented solution, they used digital signatures without the requirement for a centralized public key infrastructure. To test the feasibility of their proposal, they implemented a Linux prototype, and their proposed solution protected the binary files of the file systems, the operating system, and applications on the disk. During testing, they showed that the prototype of the proposed protection solution provided protection against various kernel-modification-based rootkits (available and known at the time of development) while its implementation had minimal costs [PERSON] and colleagues (2018). The IoT, cloud, fog, and edge computing architectures represent a number of risks: can data be kept confidential, and can integrity and availability be maintained? How can information loss, prolonged denial of data access, information leakage, or technical failures be avoided? In their study [PERSON] et al. (2018), [PERSON] et al. proposed a customizable, robust, redundant storage system which is able to verify the encrypted data and validate operations. Their system used the redundant residual number system (RRNS) and a new process for error correcting and key sharing. In their work, they introduced the notion of approximate ranking number value (AR), which contributed to the simplification of operations and decreased the size of the coefficients used during the RNS-to-binary conversion.