Introduction to Cybersecurity

Jeffrey Fonseca

2025-02-10

OSI Model and Our Name

Image of the 7 OSI layers

Cybersecurity is:

• Methods used to secure systems from malice or human error
• Backups!

Types of Machines

• Servers: Run things like web pages or game servers
• Desktops: Machines you normally interact with

Common Methodologies for Servers

• Limit services in use (attack surface)
• “Harden” services
• “Agent” software, which monitors systems

Methodologies for Desktops

• Restrict downloading of software
• “Agent” software to monitor systems
• Education of users

Operating Systems

• Windows, Linux, and Mac
• Windows and Mac are common for desktops
• Linux is common for servers

Overthewire Bandit

• https://overthewire.org/wargames/bandit/
• Good place to get started for Linux related things
• All answers to the challenges can be found in the built in documentation accessible via the man command.

Web Based Terminals:

• https://shell.segfault.net
• https://sshwifty-demo.nirui.org/
• https://ssheasy.com/