ICT Revision MCQ Series (AL Grade 12) . 6 Computer Networking

TCP’s reliability (retransmissions acknowledgments) adds latency making UDP’s faster unreliable transmission better for real-time applications like streaming.

Antivirus software detects and removes viruses and malware providing essential protection for networked systems.

Modulation converts digital data to analog signals for transmission over PSTN enabling connectivity between remote devices.

Error detection uses data bits as input applies a parity check to process and outputs whether an error is detected aligning with techniques like parity bits.

The system uses the device’s MAC address as input verifies it against a database (process) and outputs either access granted or denied aligning with network authentication processes.

MAC addresses identify devices in a LAN IP addresses enable global communication TCP ensures reliable data delivery and DNS resolves domain names to IP addresses aligning with networking fundamentals.

Routers deliver packets DNS resolves names NAT enables IP sharing and MAC protocols manage LAN media access aligning with Internet and LAN operations.

Modems convert digital data (input) to analog signals through modulation (process) for transmission over PSTN (output) enabling Internet connectivity.

Signal properties in data communication include amplitude frequency wavelength and phase which define signal behavior. Color is not a signal property in this context as it relates to light perception not data transmission.

DNS translates domain names to IP addresses manages namespaces and supports top-level domains. Encryption is handled by protocols like HTTPS not DNS.

Wavelength = Speed / Frequency = (3x10^8) / (10x10^6) = 30 meters. This calculation is critical for selecting appropriate transmission media in network design.

Star topology requires more cables but is manageable with a switch while bus topology uses a single cable but risks collisions making wiring complexity the key factor for scalability.

Statements a c and e are correct. Unguided media use free space (not cables) and DNS translates domain names to IP addresses not the reverse.

Analog signals are continuous and digital signals are discrete binary states. Digital signals are less susceptible to noise Wi-Fi uses digital signals and fiber optics also use digital signals.

Guided media (e.g. fiber optics) are wired unguided media (e.g. radio waves) are wireless hubs simplify wiring in star topologies and MAC protocols manage media access in networks.

Firewalls and antivirus software protect against digital threats like viruses phishing and malware but physical theft requires physical security measures not network-based solutions.

Manchester encoding includes mid-bit transitions for self-synchronization preventing data loss due to timing mismatches between transmitter and receiver.

Manchester encoding takes binary data adds mid-bit transitions for synchronization and outputs a synchronized signal ensuring reliable data transmission.

Firewall filters traffic antivirus removes malware encryption ensures confidentiality digital signatures verify authenticity and education enhances security awareness.

HTTP follows a client-server model and UDP is used for DNS. TCP provides multiplexing but IPv4 uses 32-bit addresses and routers use packet switching not circuit switching.

OSI has seven layers Transport ensures reliability Presentation handles encryption and Data Link manages MAC addresses. The Network layer uses packets not frames.

Gateway connects networks switch uses MAC addresses router routes packets hub broadcasts data and modem converts signals for PSTN connectivity.

TCP is reliable with acknowledgments UDP is connectionless and used for real-time applications and port numbers enable multiplexing. UDP is faster and TCP is used for file transfers.

Public key encryption ensures confidentiality digital signatures use private keys for authentication and education mitigates social engineering. Firewalls filter traffic not switch packets and antivirus primarily targets malware not phishing.

Wireless networks transmit signals to enable data transfer connectivity and real-time communication. Physical hardware repairs require manual intervention and cannot be performed through signal transmission alone.

Modems connect home LANs to ISPs by converting signals for Internet access a key component in home network setups.

MAC protocols manage media access switches simplify wiring DHCP assigns IPs and modems convert signals for Internet connectivity reflecting core networking functions.

Dividing /24 into 4 subnets requires 2 bits resulting in a /26 mask (255.255.255.192). Each subnet has 6 host bits supporting 2^6 - 2 = 62 hosts.

Statements a c and e are true. Star topology is efficient with a central switch and IPv6 uses 128-bit addresses not 32-bit.

A /27 mask has 5 host bits (2^5 = 32 addresses 30 usable after reserving network and broadcast addresses) used for efficient IP allocation in small networks.