IT Security Basics You Can Understand at a Glance: Master the Core Principles in One Video Without Memorizing

These are the standards for vulnerability analysis and risk assessment following the revision of the Critical Information and Communication Infrastructure standards for the second half of 2025. Additionally, this information includes an analysis of kernels and various changes based on the latest versions of Unix and Windows OS. By applying default values, you can achieve rapid risk assessment and account for various operational risks. You may use this for study purposes or for data acquisition during follow-ups to reach the highest domestic standards through prompt action.

We will show you how to use Wireshark to check actual network packets and perform everything from HTTP communication analysis to web vulnerability attack detection and malware communication analysis. We explain everything step-by-step starting from the OSI 7 layers so that even beginners without a network foundation can follow along. After taking the course, you will be equipped with the practical skills to find and analyze the specific packets you want.

While tackling Nebula, a wargame designed to develop system hacking skills, I have included a complete translation and solutions for all challenges, including the setup of the practice environment from start to finish. Additionally, you can acquire the computer science knowledge required for each challenge.

Repeatedly study the 100 most frequently appearing CPPG core topics through theory, mind maps, and problem solving.

Learn about networks easily, quickly, and engagingly with pictures and videos!

If you want to work for a long time as a super developer who can handle the entire process of service development and operations alone, building a solid foundation in IT infrastructure knowledge is just as important as learning various programming languages!

This course puts an end to operational vulnerabilities on Linux servers caused by incorrect permissions. Master file and directory permission control completely based on real-world practices.

We provide 140 sounds in 5 areas that will help you with the CPPG certification exam. We also provide an introduction to how to use the 111 questions that are automatically generated each time, and a one-time lecture and explanation.

You can understand the concept and technology of blockchain and conduct ISMS-P certification audits specialized for virtual asset exchanges.

Records remain, and responsibility grows! Everything about digital ethics that protects the workplace This course explores digital hate, digital sex crimes, and the risks of using AI that can actually occur in the workplace through case-based stories, clearly explaining what the problems are and how to prevent and respond to them. It firmly establishes the standards of digital ethics that today’s employees—who communicate digitally and use AI as part of their everyday work—urgently need, including how to work while respecting one another in digital spaces and how to use AI more safely and responsibly.

Through this course, you can study short answer and descriptive questions from past practical exams for the Information Security Engineer.

Have you heard of information security solutions, but do you know their exact roles and differences? A variety of information security solutions are used by businesses, including firewalls, IDS, IPS, WAF, DLP, and EDR! Precisely understanding the role each one performs, how it works, and in what situations it is used is an important first step toward developing your information security skills. A complete beginner’s guide to information security solutions (systems) that anyone can easily learn! Learn complex security technologies easily and systematically, starting from the basics.

Hashing, salting, JWT, symmetric and asymmetric keys, and even HTTPS and TLS. The backbone of security that we use every day yet always found vague and unsettling. If we have to face the countless neglected threats and technical debt someday, let’s properly tackle them once and for all this time.

This training will help you understand the world-famous cloud, build your own cloud environment, and strengthen your ability to use it easily.

As the adoption of generative AI accelerates, new security threats such as corporate confidential information leaks and prompt injections are surging. This course covers strategies for embedding security throughout the entire AI lifecycle, based on the National Intelligence Service (NIS) guidelines' 30 core security measures and 15 practical threat cases. It also addresses security issues in the latest AI trends, such as Agentic AI and Physical AI, and presents methods for establishing governance frameworks that can be immediately applied in practice.

This course is designed to guide those who have completed the "Mastering Core Network Theory through Memorization: Basic Course" to understand more advanced theories. It covers deeper concepts such as NAT technology, which is the operating principle of internet routers, as well as load balancing system principles and VPN technology principles. The goal of this lecture is also to finish by "memorizing" it all! You can do it!

This lecture is about automotive ECU cyber security based on a basic understanding of cryptography.

Master AWS networking completely! Learn VPC, subnet, routing, and security with a focus on practical application, and design secure and scalable cloud network architectures. Complete the core skills that every working engineer must know in a short period of time!

From analyzing the encryption mechanisms of ZIP, PDF, and MS Office files to hands-on dissection of the WannaCry ransomware, master static analysis tools and GPU-accelerated cracking techniques. This is a practical, security engineering-focused course that builds incident response capabilities through the development of next-generation malware analysis pipelines using OpenAI Codex and automated report generation.

This course is for those who want to develop packet analysis programs like Wireshark and various network solutions using the Npcap library.