Notes, summaries, assignments, exams, and problems for Technology

Experiment 01: Network Traffic Analysis in ICS/SCADA

Tools

• Wireshark

Objectives

• Use Wireshark to capture and analyze network traffic to detect anomalies such as unauthorized commands or network scanning.

Deliverable

• A detailed report of traffic patterns and recommendations for mitigations.

Wireshark

Wireshark is a network protocol analyzer used to capture and inspect data packets in real time.

Installing Wireshark on Linux

1. Step 01: Update package lists: sudo apt update
2. Step 02: Install Wireshark: sudo apt install wireshark -y
3. Step 03: Allow non-root packet capture. When prompted, select to allow non-root users to capture packets. If not prompted, run:
   • sudo dpkg-reconfigure wireshark-common
   • sudo usermod -aG wireshark $USER
4. Step 04: Restart your session (log

... Continue reading "Cybersecurity Labs for Industrial Control Systems (ICS/SCADA)" »

Cisco Router and Switch Configuration

PPP Authentication

1. User Configuration (Matching Passwords on Both Routers)

router(config)# username <hostname_remote_router> password <password>

2. Interface Encapsulation Change

router(config-if)# encapsulation ppp

3.1 Enabling PAP Authentication

router(config-if)# encapsulation ppp
router(config-if)# ppp authentication pap
router(config-if)# ppp pap sent-username <local_username> password <password>

3.2 Enabling CHAP Authentication

router(config-if)# encapsulation ppp
router(config-if)# ppp authentication chap

DHCP Scope Configuration

router(config)# ip dhcp pool <POOL_NAME>
router(config-dhcp)# network <NETWORK_ADDRESS> <NETMASK>
router(config-dhcp)# default-router <GATEWAY_

... Continue reading "Cisco Router and Switch Configuration: PPP, DHCP, VLAN, RIP, OSPF, EIGRP" »

Advanced Technology Concepts: Nanotubes and Robotics

Carbon Nanotubes: Properties and Benefits

What are Nanotubes?

Nanotubes are cylindrical molecules made of carbon atoms, possessing extraordinary strength and electrical properties.

Advantages over Traditional Materials:

• High strength
• Lightweight structure
• Excellent conductivity (electrical and thermal)
• Superior chemical stability

Androids Versus Automata

What is the difference between androids and automata?

Androids

Robots designed to resemble humans, often incorporating advanced Artificial Intelligence (AI).

Automata

Mechanical devices that perform predefined actions, typically lacking human-like design or advanced AI.

Wireless Communication and Smart Systems

Key Wireless Systems

Name two common types of... Continue reading "Essential Concepts in Nanotechnology, AI, and Smart Systems" »

Gmail Configuration and Usage

Gmail Account Setup and Basics

• How do you configure a Gmail account?
  You configure a Gmail account by signing up on Gmail and entering personal details.
• What is used to send an email?
  The "Compose" button is used to send an email.
• How can you reply to an email?
  You can reply to an email by clicking the "Reply" button.
• What does forwarding an email do?
  Forwarding an email sends the received email to another person.
• How do you attach a file in Gmail?
  You attach a file using the "Attach files" (paperclip) option.
• What information is needed to sign up for a Gmail account?
  The required information includes your name, username, password, and recovery details.
• Where do incoming emails appear in Gmail?
  Incoming emails appear in

... Continue reading "Mastering Gmail, Drive, and Google Workspace Essentials" »

Core SAP ABAP Concepts and Definitions

What is the Use of ALV (ABAP List Viewer)?

ALV (ABAP List Viewer) is a powerful tool in SAP that facilitates the creation and display of reports with enhanced functionalities and features. It is widely used in SAP to present data in a structured and user-friendly manner. ALV is part of the SAP GUI and is used to generate reports and tables that provide users with various options for interacting with data.

Understanding the SAP ABAP 3-Tier Architecture

The SAP R/3 architecture is a multi-tiered structure that comprises three main layers:

1. The Presentation Layer: This is the topmost tier, responsible for providing user interfaces for interacting with the system. It serves as the gateway for users to access and

... Continue reading "Essential SAP ABAP Interview Questions and Core Concepts" »

Memory Hierarchy: Faster, Smaller, Costlier

The computer memory hierarchy organizes storage based on speed, size, and cost, moving from the fastest (CPU internal) to the slowest (external storage):

• Registers: CPU internal (Fastest, Smallest)
• Cache: L1, L2, L3 (Fast)
• Main Memory: RAM (DRAM)
• Secondary Storage: HDD, SSD
• Tertiary Storage: Optical, Tape (Slowest, Largest)

What Is Cache Memory?

Cache memory is a small, high-speed memory located close to the CPU. It stores frequently accessed data and instructions so the processor doesn’t have to fetch them repeatedly from slower main memory (RAM).

Cache significantly reduces memory access time, thereby improving overall system performance.

Why Cache Outperforms Main Memory (RAM)

Cache memory achieves superior... Continue reading "CPU Memory Hierarchy and Cache Mapping Techniques" »

The Internet: A Global Network

The Internet is a global network of interconnected computer networks, linking billions of devices worldwide using TCP/IP. It comprises millions of networks, including private, public, academic, business, and government, and provides extensive information resources.

The History of the Internet

The Internet, originating from ARPANet, an experimental network created in the 1960s by the US military, was launched online in 1969 under a contract by ARPA, connecting four US universities. The history of the Internet reflects the continuous growth of this network, connecting millions of people, businesses, governments, schools, and universities.

The ARPANet

The ARPAnet, created in 1969, began with four computers connecting.... Continue reading "The Internet: A Comprehensive Overview" »

ELECTRICAL INSTALLATIONS:
The electricity used to meet our energy needs (housing, buildings and industries) But there are serious dangers such as fires and electrocucions if facilities do not meet the appropriate security.
Low Voltage Electrotechnical Regulations (REBT) technical conditions and guarantees must be met by electrical installations connected to a low voltage supply in order to:
-Preserve the safety of persons and property.
-Ensure the normal operation of these facilities and prevent disruptions that could cause other facilities and prevent disruptions that could cause other facilities and services.
-Contribute to the technical reliability and efficiency of economic facilities.
Complementary technical instructions (ITC - BT)... Continue reading "Domestic Electrical Installations" »

Cloud Computing Essentials

What is a Distributed File System (DFS)?

A distributed file system (DFS) in cloud computing manages data across multiple servers for scalability, fault tolerance, and efficient access. It replicates data for high availability, balances loads, ensures data consistency, and can be cost-effective.

Examples include Hadoop Distributed File System (HDFS), Google File System (GFS), Amazon Elastic File System (EFS), and Azure Blob Storage. DFS is essential for handling large-scale data storage and processing in cloud environments.

HDFS Architecture

HDFS: Hadoop Distributed File System. Google published its paper GFS and on the basis of that HDFS was developed.

It states that the files will be broken into blocks and stored in nodes... Continue reading "Cloud Computing Essentials: DFS, HDFS, Security, and Virtualization" »

Windows Server 2016 Disk Storage Types: Basic vs. Dynamic

Windows Server 2016 supports two essential disk storage types: basic disks and dynamic disks. They differ significantly in how they manage partitions and volumes:

• Basic Disks: Use traditional disk management techniques and contain primary partitions, extended partitions, and logical drives.
• Dynamic Disks: Do not use traditional partitioning. Dynamic disks offer greater flexibility than basic disks, providing virtually no restriction on the number of volumes that can be created on a single disk.

Purpose and Function of a Subnet Mask

A subnet mask is a crucial component in networking used to divide an IP address into two distinct parts: the network portion and the host portion. Its primary... Continue reading "Windows Server 2016 Fundamentals: Storage, Networking, and Security" »