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1. RBI Overview RBI (Remote Browser Isolation) is a security technology that does not run the browser in the user's local environment. Instead, it runs the browser on a server or in an isolated remote environment and delivers only the rendered screen. The browser runs in a server-side isolated environment, and users receive only the visual output. User input events are sent to the server to control the remote browser. 1.1. Limits of Web Security Today, most business activities are centered around web browsers. Web browsers have become both the most commonly used work environment and the primary entry point attackers target first. Traditional web security frameworks mostly rely on website blocking, URL categorization, and detection-stage filtering. These methods are effective against known threats but have limitations against new phishing attacks or uncategorized malware. Also, it is practically impossible to b...

1. Definition of SASE SASE (Secure Access Service Edge) is a service architecture concept and marketing term introduced by Gartner . Formalized in the report "The Future of Network Security Is in the Cloud" (2020)           1.1. Background In the past, work was done within headquarters data centers, but today users (remote workers) and business data (SaaS, cloud) are increasingly distributed. For this reason, organizations are now facing a situation where they must handle multiple incompatible technologies, increasing both complexity and cost. Traditional VPN approaches route traffic to headquarters first and then send it bac...

1. C Language Code Analysis Practice Just like language, in programming code, not only writing ability but also reading ability is important. The ability to read code becomes the foundation of analytical skills for finding bugs that occur during programming and predicting code behavior in advance. Analyze the code presented below directly without compiling it and predict the execution result. Through this, you can build code comprehension skills and practice logical thinking. 1.1. Beginner Level 1.1.1. ex01_low_if.c Understand the control flow of the if/else conditional statement. Check operator precedence in the expression a + b > c * 3 . Trace how constant values declared with const are used in condition evaluation. #include <stdio.h> int main ( void ) { const int a = 3 ; const int b = 5 ; const int c = 2 ; int result = 0 ; if (a + b > c * 3 ) { result = 1 ; } else { result = 2 ; ...

1. Integrated Example The following example is a comprehensive example that uses all five grammar elements of the C programming language (variables, operators, statements, control, and functions) and includes all 32 reserved keywords and 12 preprocessor directives under the C90 standard in a single compilable source file. from C Language - Programming Language Grammar exam.c /* * exam.c - Comprehensive C grammar example * */ // #include - include C headers #include <stdio.h> #include <stdlib.h> // #define - define macro #define MAX_COUNT 5 #define BUF_SIZE 64 #define DEBUG_LEVEL 0 // #undef - undefine macro #undef DEBUG_LEVEL #define DEBUG_LEVEL 1 // #ifndef / #endif - compile only if macro is not defined #ifndef RELEASE #define RELEASE #endif // #if / #elif / #else / #endif - conditional compilation #if DEBUG_LEVEL == 0 #define BUILD_TYPE "Release" #elif DEBUG_LEVEL == 1 #define BUILD_TYPE "Debug" ...

1. Executable File Structure We have already examined the structure of executable files through the following topic. How an Executable File Operates Just like document files are organized in a defined format, executable files also have a similar structured format. Among their components, the machine code in the .text section is loaded and executed . 2. Modifying an Executable File This means that by directly modifying the machine code stored in the .text section , the execution behavior of a program can be changed. Using this characteristic, it is possible to alter the execution result without modifying the program source code. 2.1. bin to hex Use the xxd command to convert an executable file into a text-based hex file. $ objdump -d -M intel add Disassembly of section .text: 0000000000401000 <_start>: 40...