Computer Security: Threats, Measures, and Best Practices

Posted on Jan 27, 2025 in Technology

Computer Security Fundamentals

Security: The characteristic of a system indicating it is free from danger, harm, or risk and is somehow infallible. Computer Security: A set of actions, tools, and devices needed to provide a computer system with confidentiality, integrity, and availability. Reliability: The probability that a system behaves as expected.

Objectives of Security

The core objectives are confidentiality, integrity, and availability. In a computer system, the following must be protected:

  1. Hardware, which may be affected by voltage drops, breakdowns, etc.
  2. Software, which may be affected by viruses.
  3. Data.

Threats to a Computer System

Elements that can threaten a computer system include:

  1. People (active and passive).
  2. Logical threats (malicious software and errors).
  3. Physical threats (device failure and natural disasters).

Understanding Hackers

A hacker is someone with computer skills, often at the top of the IT pyramid. They can also be intruders entering computer systems without permission.

Security Measures

Security measures include:

  1. Prevention: Passwords, access permissions, communications security, upgrades, and UPS.
  2. Detection: Antivirus, firewalls, and antispyware.
  3. Recovery: Backups.

A UPS (Uninterruptible Power Supply) provides power during power failures through its battery.

Malware and Threats

A virus is a program hidden inside another program. Malware is malicious software. Spam is unsolicited junk mail, often related to advertising. Adware is software that covertly extracts data from your computer.

Antivirus and Firewalls

Antivirus is a program that detects, blocks, and removes malware. It is useful to check if your system and antivirus are infected. A firewall is a program or hardware device that controls communications to prevent unauthorized network access.

Data Backup and Recovery

Backups are copies of data that can recover original information if needed. They are stored on external devices (DVD, hard drive, etc.). Backups include folders, files, bookmarks, emails, and other information.

To restore Windows: Go to Start > All Programs > Accessories > System Tools > System Restore. Backup Path: Go to Start > All Programs > Maintenance > Backup Center.

Risk of downloading files: Avoid downloading from unofficial sources.

Cookies: These are simple text files saved on your computer when you browse the internet.

Internet Traces: While the IP address is dynamic, the provider keeps a record of who and where each computer is connected. An IP address can identify the user and notify authorities if needed.

Protecting Your Network

Protect your wireless network:

  1. Change the default password.
  2. Use WEP/WPA.

Cryptology

Cryptology is used to protect information sent over the internet by transforming it to be incomprehensible to unauthorized recipients.

Malware Solutions

Malware solutions:

  1. Keep your computer updated (OS and antivirus).
  2. Back up your data frequently.
  3. Install legal software.
  4. Use strong passwords.
  5. Stay informed about security alerts.
How Worms Spread

Spreading worms on the internet:

  1. The spread begins with an email.
  2. The virus enters the PC.
  3. The hard drive is infected and may follow several routes.
  4. The virus multiplies using programs.
  5. The virus infects the address book.
  6. Infected emails are sent to all contacts.
  7. The virus affects shared files (eMule).
  8. Infected files are distributed on the internet.
  9. The virus enters the Wi-Fi network.
  10. Once on the local network, it spreads to all connected equipment.