Essential SQL Commands and Operations

Posted by on Feb 24, 2025 in Computing and Communications | 0 comments

CREATE: Create a New Table

CREATE TABLE employees (
  employee_id INT PRIMARY KEY,
  first_name VARCHAR(50),
  last_name VARCHAR(50),
  department VARCHAR(50),
  salary DECIMAL(10, 2)
);

INSERT INTO: Add New Records

INSERT INTO employees (employee_id, first_name, last_name, department, salary)
VALUES
  (1, 'John', 'Doe', 'HR', 50000.00),
  (2, 'Jane', 'Smith', 'IT', 60000.00),
  (3, 'Alice', 'Johnson', 'Finance', 55000.00),
  (4, 'Bob', 'Williams', 'IT', 62000.00),
  (5, 'Emily', 'Brown', 'HR',
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Configuring Network Devices: Police, Fire, and Central HQ

Posted by on Feb 23, 2025 in Computing and Communications | 0 comments

This document outlines the configuration steps for network devices in a Police Department, Fire Department, and Central Headquarters environment. It includes router and switch configurations, VLAN setup, OSPF routing, DHCP configuration, and NAT setup.

Network Topology

The network consists of three main sites:

  • Police Department (Site 1)
  • Central Headquarters (HQ)
  • Fire Department (Site 2)

Router Configurations

Police Department Router Configuration

Router(config)# hostname PoliceDept
PoliceDept(config)# no
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OSPF Configuration: Multi-Router Setup

Posted by on Feb 22, 2025 in Computing and Communications | 0 comments

OSPF Configuration for Multiple Routers

RTR-1 Configuration

enable
configure terminal
router ospf 10
exit
interface g0/0/0
ip ospf 10 area 0
interface s0/1/0
ip ospf 10 area 0
exit
router ospf 10
router-id 9.9.9.9
exit
interface g0/0/0
ip ospf priority 255
exit
ip route 0.0.0.0 0.0.0.0 s0/1/1
router ospf 10
default-information originate
exit
interface s0/1/0
ip ospf hello-interval 20
ip ospf dead-interval 80
exit
router ospf 10
auto-cost reference-bandwidth 10000
exit
router ospf 10
passive-interface
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Web Servers, FTP, and Content Management: A Technical Deep Dive

Posted by on Feb 14, 2025 in Computing and Communications | 0 comments

Update Content

Internet and Web Servers

Websites are hosted on computers called Web Servers. These servers use programs that accept requests from clients.

Examples of Web Servers:

  • IIS (Internet Information Server)
  • PWS (Personal Web Server)
  • WAMP (Windows + Apache + MySQL + PHP)
  • LAMP (Linux + Apache + MySQL + PHP)
  • XAMPP
  • Apache (.php)
  • Apache Tomcat (Pages .jsp)

Server Types

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Network Configuration: Routers and Switches Setup

Posted by on Feb 14, 2025 in Computing and Communications | 0 comments

Router R1 Configuration

hostname R1

interface FastEthernet0/0.10
 encapsulation dot1Q 10
 ip address 10.0.0.1 255.255.248.0

interface FastEthernet0/0.20
 encapsulation dot1Q 20
 ip address 10.0.8.1 255.255.252.0

interface FastEthernet0/0.30
 encapsulation dot1Q 30
 ip address 10.0.12.1 255.255.252.0

interface FastEthernet0/0.40
 encapsulation dot1Q 40
 ip address 10.0.16.1 255.255.255.0

interface FastEthernet0/0.99
 encapsulation dot1Q 99
 ip address 1.1.1.1 255.0.0.0

interface FastEthernet0/
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OpenSSL: Symmetric Encryption Algorithms & Examples

Posted by on Feb 8, 2025 in Computing and Communications | 0 comments

Symmetric Encryption Algorithms with OpenSSL

Encrypt the file “fichero.txt” using the RC4 symmetric encryption algorithm

OpenSSL> rc4 -in c:\cifrado\fichero.txt -out c:\cifrado\cifrado.rc4
enter rc4 encryption password:
Verifying - enter rc4 encryption password:

Decrypt the previous file:

OpenSSL> rc4 -d -in c:\cifrado\cifrado.rc4 -out c:\cifrado\descifrado.txt
enter rc4 decrypt password:

DES

Encrypt:

OpenSSL> des -salt -in c:\csb.log -out c:\csb.bf.txt
enter des-cbc encryption password:
Verifying
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