Quick Revision

GK One-Line Question & Answer

15541+ short questions with short answers, covering every category and sub-category on the site — no long articles to scroll through. Good for a fast recap before an exam, or a few minutes of daily practice.

Looking for exam process/strategy questions instead? Try the Exam Preparation FAQ →

Computer Fundamentals → Introduction to Computer 40

PoE (Power over Ethernet) provides?
DC power over Ethernet cables to devices (IP cameras, APs)
click to copy
Which organization assigns globally unique MAC addresses?
IEEE (first 3 bytes = OUI)
click to copy
Unicast MAC address has LSB of first byte?
Set to 0
click to copy
Broadcast MAC address is?
FF:FF:FF:FF:FF:FF
click to copy
Which protocol detects IP address conflicts on a network?
Gratuitous ARP
click to copy
ICMP type 0 is?
Echo Reply
click to copy
ICMP type 11 (Time Exceeded) is used by?
traceroute
click to copy
TCP RST flag is used to?
Abruptly terminate connection
click to copy
TCP FIN flag initiates?
Graceful connection close
click to copy
TCP sequence numbers provide?
In-order delivery and reliable data reassembly
click to copy
TCP sliding window implements?
Flow control — limits sender based on receiver buffer space
click to copy
TCP slow start algorithm?
Begins with small congestion window, doubling until threshold
click to copy
CUBIC is a?
TCP congestion control algorithm (default in Linux)
click to copy
QUIC protocol developed by Google uses?
UDP as transport, providing reliability and security like TCP+TLS
click to copy
HTTP/3 is built on?
QUIC (over UDP)
click to copy
WebSocket provides?
Full-duplex persistent connection over single TCP connection
click to copy
Which attack exploits the same origin policy weakness in browsers?
CSRF (Cross-Site Request Forgery)
click to copy
CSRF token prevents CSRF by?
Including unpredictable token in each form submission verified by server
click to copy
Same-Origin Policy (SOP) in browsers restricts?
Scripts from one origin accessing resources of another origin
click to copy
CORS (Cross-Origin Resource Sharing) allows?
Controlled cross-origin requests via HTTP headers
click to copy
Content Security Policy (CSP) prevents?
XSS by controlling which resources the browser may load
click to copy
Path traversal attack attempts to?
Access files outside web root using ../ sequences
click to copy
Command injection attack allows?
Executing arbitrary OS commands through vulnerable input fields
click to copy
Buffer overflow attack overwrites?
Adjacent memory including return address to redirect execution
click to copy
Stack canary protection prevents?
Stack buffer overflows by detecting overwrite before function return
click to copy
ASLR (Address Space Layout Randomization) randomizes?
Memory addresses of process components to hinder exploits
click to copy
DEP/NX (Data Execution Prevention) prevents?
Execution of code from non-executable memory regions (stack/heap)
click to copy
ROP (Return-Oriented Programming) attack bypasses?
DEP/NX by chaining existing code gadgets
click to copy
Which tool is used for network packet capture?
Wireshark
click to copy
Nmap is used for?
Network scanning and host discovery
click to copy
Metasploit is used for?
Penetration testing — developing and executing exploits
click to copy
Nessus is a?
Vulnerability scanner
click to copy
Burp Suite is used for?
Web application security testing (intercepting proxy)
click to copy
John the Ripper is used for?
Password cracking
click to copy
Hashcat is used for?
GPU-accelerated password hash cracking
click to copy
Which password attack tries all possible combinations?
Brute force
click to copy
Rainbow table attack uses?
Pre-computed hash-to-password mappings for fast lookup
click to copy
Salt prevents rainbow table attacks by?
Adding unique random data to each password before hashing
click to copy
Which is the most secure password hashing algorithm?
bcrypt/Argon2
click to copy
Argon2 won the Password Hashing Competition (PHC) in?
2015
click to copy