Introduction In the world of Linux, everything is a file. From ordinary documents to system devices and process interfaces, all exist in the form of files. To ensure system security and reliability, strict permission control must be enforced on these files. Today, we will delve into understanding the Linux file system’s permission model, how permissions … Read more
Smart Access Control Solution Based on AI MCU M55M1 Application Background Traditional smart access control systems primarily achieve security protection through technologies such as biometric recognition, alarm linkage, and real-time monitoring. They are widely used in factories, financial institutions, medical facilities, public safety areas, commercial venues, and residential areas. However, these solutions have the following … Read more
On the surface, the storm has calmed; but in reality, undercurrents are surging. The Dutch government has just announced the “suspension of the seizure” of Nexperia, a subsidiary of China’s Wingtech Technology,Nexperia, and the Chinese Ministry of Commerce immediately expressed its “welcome”. However, Wingtech directly stated:“We absolutely do not accept!” Why? Because the real knife … Read more
Multidimensional arrays are arrays composed of multiple one-dimensional arrays, where each one-dimensional array is referred to as a sub-array. Similar to one-dimensional arrays, each element of a multidimensional array can be of any type; for example, integer, character, floating-point, etc. The declaration format for multidimensional arrays is as follows. Initialization of Multidimensional Arrays Multidimensional arrays … Read more
Translation: https://www.javacodegeeks.com/2025/09/secure-mqtt-implementations-tls-authentication-and-access-control-for-iot-networks.html MQTT has become the de facto standard protocol for IoT communication: lightweight, reliable, and designed for resource-constrained devices. However, while MQTT simplifies communication between devices, it does not inherently provide security guarantees. Without proper safeguards, your IoT network may be vulnerable to eavesdropping, spoofing, or unauthorized access. This article will explore how to … Read more
Understanding your needs, Linux system security is an important assessment content in the Information Security Engineer examination. I have designed a 5-day Linux crash course closely aligned with the exam points, incorporating analyses of past exam questions to help you prepare efficiently. To prepare for the exam, knowledge related to Linux may appear in multiple-choice … Read more
Previously, we wrote an article about the NVL72 interconnection scheme. Some users in the community requested a further explanation of what these different cables in data centers mean. Let’s review where optical connections and copper connections are used in the GB200 standard. The abandoned NVL72 optical interconnection scheme regarding the GB200 architecture and interconnections has … Read more
1. Core Logic and Industry Background of System Hardening In the global cybersecurity threat landscape of 2025, APT attacks and ransomware supply chain incidents are frequent. As a standard platform for penetration testing and security research, the hardening of Kali Linux needs to establish a closed-loop system of “proactive defense – dynamic monitoring – rapid … Read more
In daily Linux system administration, we often need to control which hosts can access our services. Today, we will provide a detailed introduction to two powerful access control files: <span>hosts.allow</span> and <span>hosts.deny</span>, to enhance system security. 1. Introduction to hosts.allow and hosts.deny Files These two files are configuration files for TCP Wrappers, used to control … Read more
Smart locks, as an important component of the smart home ecosystem, bring great convenience to users’ daily lives, but the accompanying security risks cannot be ignored. In the field of smart locks, the ease of copying card keys is a prominent issue and security concern. In the field of smart access control and locks, the … Read more
