Networks MCQ — 21 Practice Questions with Answers

Explanation

WPA2 is the second generation of Wi-Fi Protected Access and was made mandatory for Wi-Fi CERTIFIED devices before later WPA3 adoption. WPA is the older protocol, while WPS is mainly a setup mechanism rather than the main protocol used to secure Wi-Fi traffic. Therefore B is correct.

Explanation

Option A is correct because GPS uses code-division spread-spectrum signalling: satellites are distinguished by unique pseudo-random codes. FDMA and TDMA divide access by frequency or time slots, which is not the basic multiple-access principle used to identify GPS satellite signals.

Explanation

The default TCP port for HTTP web traffic is 80. Port 25 is used for SMTP, 20/21 for FTP, and 23 for Telnet. Hence A is correct.

Explanation

Hamming distance is the basis for designing codes that can both detect and correct errors by ensuring enough bit differences between valid codewords. A single parity check can usually detect only one-bit errors, while CRC and checksum are primarily error-detection techniques. Hence B is the appropriate choice.

Explanation

DDoS expands to Distributed Denial-of-Service. It is an attack in which many distributed systems flood a target service so legitimate users cannot access it. Therefore B is correct; the other expansions change the standard meaning.