Cybersecurity Boot Camp Review - Blocks 01 to 05

Flashcard deck covering fundamental concepts from Cybersecurity Boot Camp Blocks 01 through 05.

What are the seven layers of the OSI Model in order from Layer 1 to Layer 7?

Layer 1: Physical, Layer 2: Data Link, Layer 3: Network, Layer 4: Transport, Layer 5: Session, Layer 6: Presentation, Layer 7: Application.

How do the 7 layers of the OSI model map to the 4 layers of the TCP/IP model?

OSI Application, Presentation, and Session map to TCP/IP Application; Transport maps to Transport; Network maps to Internet; Data Link and Physical map to Network Access.

What is a MAC address and how is its 48-bit structure divided?

A MAC address is a unique 48-bit identifier for a NIC written as six groups of hexadecimal digits. The first 24 bits are manufacturer-related and the remaining 24 bits are the device-specific identifier.

What are the four functional steps performed by a network switch?

1. Learning (stores device MAC addresses in a MAC address table), 2. Forwarding (sends data toward the correct port), 3. Filtering (limits traffic to intended devices), and 4. Loop prevention (prevents network loops).

Which ICMP message types are used by the ping utility?

ICMP type 8 (Echo Request) and ICMP type 0 (Echo Reply).

What ICMP message type does traceroute use to discover routers/hops along a path?

ICMP type 11 (Time Exceeded).

What is the purpose of the shebang (#!/bin/bash) in a shell script?

It is the first line of a script that tells the system which interpreter (e.g., Bash) should execute the script.

What is the difference between the > and >> redirection operators in Bash?

The > operator redirects output to a file by overwriting its existing contents, whereas >> appends output to the end of the file without overwriting.

How do the command chaining operators && and || differ in Bash?

&& runs the next command only if the previous command succeeds, whereas || runs the next command only if the previous command fails.

In the cleanup command find . -type f -mtime +7 -print -exec rm {} \;, what does each flag signify?

. searches current directory; -type f matches files only; -mtime +7 selects files modified >7 days ago; -print prints matching filenames; -exec rm {} \; executes rm on each match.

What does the ip a command display during network troubleshooting?

It displays interface addresses and network configuration to identify the IP addresses assigned to the local system.

What diagnostic information does the dig command return?

It performs detailed DNS lookups and returns domain information such as addresses, name servers, and DNS records.

How does mtr differ from traceroute and ping?

mtr combines ping-like response measurements with route/path visibility in real time to observe path performance over time.

Which CIA Triad goals are addressed by restricting read and write file permissions in Linux?

Restricting read permission protects Confidentiality (preventing unauthorized disclosure), while restricting write permission protects Integrity (preventing unauthorized modification).

What are the numeric octal permission values for read, write, and execute in Linux?

Read (r) = 4, Write (w) = 2, Execute (x) = 1.

What permissions are granted by the octal notation chmod 754?

Owner = rwx (7), group = r-x (5), other = r-- (4), resulting in string -rwxr-xr--.

What is the key difference between execute (x) permission on a file versus a directory?

On a file, x allows executing it as a program or script. On a directory, x allows traversing/entering the directory and accessing items by name.

Why is executing chmod 777 considered a security risk?

It grants maximum read, write, and execute permissions to owner, group, and everyone else, violating the principle of least privilege and creating potential security vulnerabilities.

What command changes both the file owner and group owner of file.txt simultaneously?

sudo chown new_owner:new_group file.txt

What is the fundamental difference between the Linux kernel and a Linux distribution?

The Linux kernel is the core component that manages hardware and resources, whereas a distribution packages the kernel with selected utilities, libraries, applications, and package management tools.

What are the primary roles of the /etc and /var directories in Linux?

/etc stores system and application configuration files, while /var holds variable/changing data such as log files.

How do you distinguish an absolute path from a relative path in Linux?

An absolute path begins with the filesystem root / and gives the full path from root, whereas a relative path does not start with / and is interpreted relative to the current working directory.

What command makes a script file named example.sh executable?

chmod +x example.sh

What terminal shortcut interrupts or stops a currently running foreground command?

Ctrl + C

What is the main operational difference between RAM and secondary Storage?

RAM is fast, temporary, volatile memory for active programs that loses contents without power, whereas Storage (HDD/SSD) provides persistent long-term data retention.

What is the difference between Type 1 and Type 2 hypervisors?

A Type 1 (bare-metal) hypervisor runs directly on physical hardware, whereas a Type 2 (hosted) hypervisor runs on top of an existing host operating system.

What are the respective roles of Kali Linux and Metasploitable in the course lab?

Kali Linux serves as a security-focused Linux toolbox, while Metasploitable serves as an intentionally vulnerable VM for controlled security testing.

What is the security principle of least privilege?

Granting users, scripts, or applications only the minimum necessary access and privileges required to perform their specific tasks.