SEARCH KEYWORD -- POPULAR COLOR



  Is Java Set ordered or not?

“Is Java Set ordered or not? ” is the most popular question asked when you interview for a Java Developer position. Many fail to answer it, and I have to admit I was one of the many. I have known the answer is “Yes and No” for a long time. No. HashSet is not ordered. Yes.TreeSet is ordered. If the interviewer continues with some follow up questions, I’m not confident that I know the answer then. Why is TreeSet ordered? Are there any other ordered S...

   ORDER,SORTEDSET,HASHSET,JAVA     2021-02-11 06:55:00

  Microsoft unveils a new logo

When releasing Windows 8, many people thought that Microsoft would use the blue logo as company's logo. But we are "cheated", Microsoft unveils a new logo. Watch video below. Since unveiling its first logo in 1977, Microsoft has changed its logo a few times, they are  In 1977, its "Micro-Soft" Microsoft "blibbet" logo, filed August 26, 1982 at the USPTO and used until 1987. Microsoft "Pac-Man" logo, designed by Scott Baker and used from 1987 to 2012 with the 1994–2002 slogan"W...

   Microsoft,Logo,Windows 8     2012-08-23 20:04:03

  Power Grid OT Simulation System

Mini OT-Energy-System Cyber Security Digital Twin Figure-00: Power_Grid_OT_Simulation_System Environment Diagram, version v0.1.2 (2024) Project Design Purpose: The primary objective of this project is to develop a scaled-down Operational Technology (OT) digital twin/equivalent — an advanced software simulation system capable of emulating the functionality of an small-sized 18KW (560+MkWh/year) hybrid power grid. This system will meet the requirements for cybersecurity training, exercises...

       2024-10-13 09:00:12

  Python PLC Honeypot Project

Program Design Propose : This project aims to develop a sophisticated honeypot system that emulates an OT (Operational Technology) SCADA network environment, bridging Level 1 OT field controller devices (PLCs) with Level 2 control programs, including Human-Machine Interfaces (HMIs). This honeypot will simulate various PLC models from major vendors, such as Schneider and Siemens, while supporting the primary communication protocols Modbus-TCP and Siemens-S7Comm. The system will integrate essenti...

       2024-11-25 03:56:49

  Why cannot compare double values directly for equality?

A question in PHP: Get some value from the database and use floatval() to convert it to floatint point value, then compare it with another value which is also converted to floating point value with floatval(). These two values are the same when using var_dump() to output, the two outputs are float(8.87), they are the same. But when comparing them for equality, the result is weird., they are not equal. Why?To analyze this question, we need to start with PHP data types. PHP uses weak types. In PHP...

   PHP,floating, precision,compare,equality     2012-06-27 09:01:36

  Efficiency of code execution

If you want to optimize your program codes, you need to find their Hotspot, i.e, the codes which are executed most frequently. If you can optimize this portion of codes a bit, you may gain much improvement of your code efficiency. Here I give you three examples about efficiency of code execution.1. PHP's Getter and Setter (From Reddit)This example a quite simple, you can skip it if you want.Consider the code below, we can find it's slower when we use Getter/Setter method to read a member variabl...

   Code, Efficiency,Analysis,Trick     2012-07-13 10:59:21

  IT System Cyber Attack Case Study 01: Malicious Macro and Backdoor Trojan Attack on IT-Network

Project Design Purpose: The objective of this cyber attack case study is to develop a workshop showcasing a practical demonstration of a red team attacker implementing an IT system/network attack via a Malicious Macro MS-Office-Word file (CVE-2015-1641) and phishing email generation program to penetrate multiple layers of firewall defenses and implant a backdoor trojan into the railway system's OT network. Related Links: GitHub Project Link , LinkedIn Post Link Attacker Vector: Malicious Macro ...

       2024-08-03 08:21:49

  Google launches Google Keep

According to Tencent Tech, Google announced the launch of Google Keep on Wednesday This is a note application similar to Evernote, its philosophy is to help you save everything you want to remember, including text and images and other notes, they can be instantly synchronized among different devices so that users can get the information they want at any time. This is a free service, it provides support for Web and Android 4.0 or later devices, users can navigate to Drive.Google.com/Keep or downl...

   Google Keep,Evernote,Synchronization     2013-03-21 13:00:02

  The First Bite on etcd Code

Etcd, one of the crucial components of Kubernetes. If APIServer is the heart, then etcd is the blood vessel that sends the end state of Kubernetes resources to various “organs”, providing high-speed, stable storage, and supporting APIServer’s high load performance. What if the etcd is not working properly? Just the condition as someone has a vascular disease. The deeper you know about them, the better diagnose you can make when issues occur. from unspl...

   SOURCE CODE,ETCD     2022-02-12 01:03:14

  IoT System Cyber Attack Case Study 02: Python Deserialization Attack and Library Hijacking Attack

Project Design Purpose: The objective of this cyber attack case study is to develop a workshop that demonstrates how a red team attacker can permanently compromise a people detection radar IoT device. The attack path is achieved through a series of attacks, including traffic eavesdropping, data deserialization attacks, web shell attacks, remote command/code execution, and Python library hijacking attacks. This case study is intended for IoT and data security professional training, aiming to ill...

       2024-07-14 01:40:09