Network Security: iptables, Nmap, Snort & Crypto Reference

Posted by on Apr 27, 2025 in Computers | 0 comments

Midterm 1 Review

  1. Find problems with the following rules and correct them:

    • a) iptables -A -S 192.168.0.0/16 -j DROP

      Correction: The rule is syntactically incorrect. -S is used to list rules, not specify a source. Assuming the intent was to block traffic *from* the source network, it should be: iptables -A INPUT -s 192.168.0.0/16 -j DROP (or specify the correct chain like FORWARD/OUTPUT).

    • b) nmap -sS -f -mtu -p 80 192.168.56.103

      Correction: The --mtu option requires a value (a multiple of 8). Example correction:

Read More

Understanding Programs, Processes, and OS Management

Posted by on Apr 24, 2025 in Computers | 0 comments

A program is not static; it is a set of instructions that, once executed, solves a problem. It represents something that does not change.

A process is dynamic; it is a piece of a program that is running, along with everything this implies: values of registers, variables, the contents of the program counter, etc.

The operating system is responsible for the following activities related to the management of processes:

  • Creating processes (both system and user)
  • Planning processes
  • Providing mechanisms for
Read More

Database Concepts: Architecture, SQL, Normalization, Keys

Posted by on Apr 21, 2025 in Computers | 0 comments

Database Architectures

Database architectures define how a database system is structured and how its components interact. Common architectures include 1-Tier, 2-Tier, and 3-Tier.

1-Tier Architecture

  • In this architecture, the database is directly available to the user. This means the user can directly sit on the DBMS and use it.
  • Any changes done here will directly be done on the database itself. It doesn’t provide a handy tool for end users.

The 1-Tier architecture is used for the development of local

Read More

Understanding Computer Basics: Hardware, Software, and Components

Posted by on Apr 18, 2025 in Computers | 0 comments

Understanding Computer Basics

Information: Part of the technology that deals with the automatic processing of information, necessary equipment, means of communication, and data storage. For information to be processed, there must be a transmitter, a receiver, a means, and a support.

Computer

A group of electronic devices whose function is the automatic processing of information. Computers are able to distinguish two states:

  • Open: When no current is present, represented by a 0.
  • Closed: When current is
Read More

NumPy Advantages in Data Science: Speed and Power

Posted by on Apr 17, 2025 in Computers | 0 comments

NumPy Advantages in Data Science

NumPy is a core library for numerical computing in Python, widely used in data science for its efficiency and powerful features. It simplifies working with large datasets, multi-dimensional arrays, and complex numerical operations. Below are the key advantages of using NumPy:

1. Efficient Data Storage and Processing

  • Memory Efficiency: NumPy arrays (ndarrays) are stored in contiguous memory blocks, unlike Python lists, making data access and manipulation faster and more
Read More

Understanding Computer Systems

Posted by on Apr 13, 2025 in Computers | 0 comments

Hardware and Software Fundamentals

Introduction

Computer systems consist of two main components: hardware and software. Hardware refers to the physical elements of a computer, while software comprises the instructions and data that control the hardware.

Software

Software can be categorized into:

  • Application Software: Programs designed for specific tasks, such as word processing or gaming.
  • System Software: Programs that manage and control the computer’s hardware, including the operating system (OS) and
Read More