Digital video surveillance systems are now common in the security infrastructure of modern times, but proprietary file systems provided by large manufacturers are a major challenge to the work of the forensic investigator. This paper proposes a forensic recovery methodology of Hikvision and Dahua surveillance systems by utilizing three major innovations: (1) adaptive temporal sequencing, which dynamically changes gap detection thresholds; (2) dual-signature validation with header–footer matching of DHFS frames; and (3) automatic manufacturer identification. The strategy puts into practice direct binary analysis of proprietary file systems, frame-based parsing and automatic video reconstruction. Testing on 27 surveillance hard drives showed a recovery rate of 91.8, a temporal accuracy of 96.7% and a false positive rate of 2.4%—the lowest of the tools tested with statistically significant improvements over commercial tools (p < 0.01). Better results with fragmented streams (87.2 vs. 82.4% with commercial tools) meet key forensic needs of determining valid evidence chronology. The open methodology offers the necessary algorithmic transparency to be court-admissible, and the automated MP4 conversion with metadata left intact makes the integration of forensic workflow possible. The study provides a scientifically validated approach to proprietary surveillance formats, which evidences technical innovativeness and practical usefulness to digital forensics investigations.

With the increasing prevalence of Internet of Things (IoT) devices in areas like authentication, data protection, and access control, general purpose microcontrollers (MCUs) have become the primary platform for security-critical apps. However, the expense of these attacks has decreased significantly in recent years, making them a viable threat to MCU-based devices. We present a framework-driven perspective with a comparative survey of MCU fault injection resilience for IoT. The survey supports—and is organized around—the procedural evaluation framework we introduce. We discuss the basic requirements for security first, and then categorize the common types of hardware intrusion, including side-channel attacks, fault injection attacks, and invasive methods. We synthesize reported security technologies employed by MCU vendors, such as TrustZone/TEE, Physical Unclonable Functions (PUF), secure boot, flash encryption, secure debugging, and tamper detection, in the context of FIA scenarios. A comparison of representative MCUs—STM32U585, NXP LPC55S69, Nordic nRF54L15, Espressif ESP32-C6, and Renesas RA8M1—highlights cost–security trade-offs relevant to token-class deployments. We position this work as a framework/perspective: an evidence-first FI evaluation protocol for token-class MCUs, a portable checklist unifying PSA/SESIP/CC expectations, and a set of concrete case studies (e.g., ESP32-C6 secure boot hardening). We do not claim a formal systematic review.

In the context of the rapid growth of security threats to mobile devices, information protection becomes a critically important task. The article is an overview of modern advanced technologies used for the development of secure mobile communication devices and crypto-smartphones. A bibliometric analysis was conducted using the Bibliometrix tool. The main principles for organizing secure communication have been classified. Innovative approaches are being considered to ensure data integrity and confidentiality. The latest achievements in the field of mobile communication security are also being analyzed. During the research, an informational and patent search for inventions in the field of mobile communication protection was conducted, and a comparative analysis of the advantages and limitations was carried out. The analysis conducted showed that some decisions create a false sense of security, as they propose the adoption of unconventional methods that do not align with well-established and widely accepted safety recommendations. The article describes the main crypto smartphones, each possessing unique characteristics and designed for specific user needs based on their functional capabilities. The provided examples of successful implementations and research demonstrate the significance of innovative solutions for enhancing the security of mobile communications and protecting personal data in the context of the modern digital world.

Video footage from proprietary surveillance systems is central to criminal investigations, yet its forensic recovery remains poorly supported. Conventional carving fails on Dahua systems because the proprietary DHFS4.1 file system uses frame encapsulation, header-footer validation pairs and embedded checksums. This paper addresses two open questions: how each of the four DHFS4.1 validation levels affects the false discovery rate (FDR) and recovery rate, and how quick formatting and partial bulk zero-fill overwriting differ in their impact on recovery. The technique combines dual-signature frame validation, frame-size and checksum consistency checking, and adaptive time sequencing, extending our earlier pipeline; the principal contribution is the validation-level ablation, the paired comparison against three independent tools, and the partial-overwrite study. All methods were executed on forensic images of eleven Dahua NVR hard drives acquired behind a hardware write blocker, so every comparison is paired within drive. The proposed method achieved a recovery rate (RR) of 88.0%, a temporal accuracy (TA) of 89.0% and a file-level FDR of 4.0%; four-level validation reduced the frame-level FDR 13.5-fold, from 27.0% (single signature) to 2.0%, at the cost of a 3.2-percentage-point drop in RR. The RR advantage over each compared tool was statistically significant (paired-samples t-test, n = 11, p < 0.05) and confirmed by the Wilcoxon signed-rank test. Quick formatting still permitted 76% recovery, whereas bulk zero-fill reduced it to 34% and raised the file-level FDR to 41%; a collision analysis shows that this increase stems from payload fragmentation rather than chance signature matches. Within the tested scope, the methodology performs comparably to commercial tools and, because every decision rule is published, is re-implementable and transparent. The findings offer practical guidance for prioritising evidence collection from Dahua surveillance systems.