15 extra multiple-choice questions for Network Examples and Protocols (12th Standard Computer Applications, Samacheer Kalvi), beyond the ones printed in the textbook — each with the correct option highlighted and a clear, worked explanation. Free to read in English and Tamil.
Q1
According to the protocol classification in the textbook, which of the following is categorized specifically as a Network Security Protocol?
- A. Transmission Control Protocol (TCP)
- B. Simple Network Management Protocol (SNMP)
- C. Secure File Transfer Protocol (SFTP)Correct
- D. Internet Control Message Protocol (ICMP)
Explanation. Secure File Transfer Protocol (SFTP) is classified as a Network Security Protocol because it ensures security over network communications, unlike TCP, ICMP, or SNMP.
Q2
In the context of the Internet of Things (IoT), what must be assigned to an everyday object so that it can collect and transfer data over a network without manual assistance?
- A. MAC Address
- B. Port Number
- C. Domain Name
- D. IP AddressCorrect
Explanation. The textbook defines the 'thing' in IoT as an everyday object that has been assigned an IP address, enabling it to communicate without manual intervention.
Q3
What networking device functions as a protocol converter by connecting two networks that run on entirely different protocols, such as an Intranet to the outside Internet?
- A. Repeater
- B. GatewayCorrect
- C. Bridge
- D. Hub
Explanation. A gateway computer acts as a protocol converter, allowing connection and translation between two networks that use different protocols.
Q4
Which mobile telephone communication system formed the basis of the analog First Generation (1G) mobile networks launched in 1981?
- A. GSM (Global System for Mobile)
- B. GPRS (General Packet Radio Service)
- C. NMT (Nordic Mobile Telephone)Correct
- D. UMTS (Universal Mobile Telecommunications System)
Explanation. The First Generation (1G) analog mobile networks were based on the Nordic Mobile Telephone (NMT) system, launched in 1981.
Q5
Which data service was launched in the year 2000 during the 2.5G bridge period to allow mobile devices to transmit picture messages and e-mails?
- A. GSM (Global System for Mobile)
- B. GPRS (General Packet Radio Service)Correct
- C. NMT (Nordic Mobile Telephone)
- D. EDGE (Enhanced Data rates for Global Evolution)
Explanation. GPRS (General Packet Radio Service) was introduced during the 2.5G transition period as a packet-switched data service for sending emails and picture messages.
Q6
Which technology allows GPRS-based mobile networks to increase their data transfer rates to a maximum speed of 384 kbit/s?
- A. 3G (UMTS)
- B. EDGE (Enhanced Data rates for Global Evolution)Correct
- C. LTE (Long-Term Evolution)
- D. GSM data transmission
Explanation. EDGE (Enhanced Data rates for Global Evolution) upgraded 2.5G GPRS data rates from 115 kbit/s up to a maximum of 384 kbit/s.
Q7
Which generation of mobile networks first introduced seamless roaming across assorted IP networks (such as GPRS, UMTS, and WLAN) by supporting a unique IP address for each mobile device?
- A. Second Generation (2G)
- B. Third Generation (3G)
- C. Fourth Generation (4G)Correct
- D. Fifth Generation (5G)
Explanation. Fourth Generation (4G) networks allow mobile devices to roam logically across different IP networks by providing an IP address to each device.
Q8
Who is the university professor credited with coining the term 'Li-Fi' (Light Fidelity) for wireless communication using light-emitting diodes?
- A. Tim Berners-Lee
- B. Harald HaasCorrect
- C. Paul Mockapetris
- D. Jon Postel
Explanation. Professor Harald Haas of Edinburgh University coined the term Li-Fi, which uses LEDs rather than radio frequencies for high-speed wireless data transmission.
Q9
According to the textbook description, what are the two core physical parts that make up a Radio Frequency Identification (RFID) system?
- A. A transmitter and an access point
- B. A reader and a tag (or label)Correct
- C. An encoder and a decoder
- D. An antenna and a base station
Explanation. An RFID system consists of two primary components: a reader to receive signals and a tag (or label) attached to the tracked object.
Q10
At which layer of the Open System Interconnection (OSI) reference model do encryption and decryption protocols, such as Secure Sockets Layer (SSL), operate?
- A. Session Layer (Layer 5)
- B. Presentation Layer (Layer 6)Correct
- C. Application Layer (Layer 7)
- D. Transport Layer (Layer 4)
Explanation. Encryption and decryption processes, including SSL, are executed at Layer 6, the Presentation Layer, of the OSI model.
Q11
Which OSI reference model layer contains simple local area protocols such as '802.3 for Ethernet' and '802.11 for Wi-Fi'?
- A. Physical Layer
- B. Data Link LayerCorrect
- C. Network Layer
- D. Session Layer
Explanation. The Data Link Layer (Layer 2) is responsible for framing and error detection, utilizing standards like IEEE 802.3 and 802.11.
Q12
Which network protocol is specifically responsible for mapping logical IP addresses to physical MAC hardware identification numbers on a local network?
- A. Internet Protocol (IP)
- B. Domain Name System (DNS)
- C. Address Resolution Protocol (ARP)Correct
- D. Simple Mail Transfer Protocol (SMTP)
Explanation. The Address Resolution Protocol (ARP) resolves logical network IP addresses to physical hardware Medium Access Control (MAC) addresses.
Q13
Which network protocol is used by routers and other network devices to send diagnostics, error messages, and operational information?
- A. Transmission Control Protocol (TCP)
- B. Internet Control Message Protocol (ICMP)Correct
- C. User Datagram Protocol (UDP)
- D. File Transfer Protocol (FTP)
Explanation. The Internet Control Message Protocol (ICMP) is used by network hardware to report transmission errors and share operational status.
Q14
Which protocol in the transport layer is connection-oriented and guarantees the reliable delivery of data packets between two hosts?
- A. Internet Protocol (IP)
- B. User Datagram Protocol (UDP)
- C. Transmission Control Protocol (TCP)Correct
- D. Address Resolution Protocol (ARP)
Explanation. Transmission Control Protocol (TCP) is a connection-oriented protocol that ensures reliable end-to-end data delivery between network hosts.
Q15
Which of the following describes the reliability characteristic of the Internet Protocol (IP) as a routable protocol?
- A. It is highly reliable and guarantees delivery of all packets.
- B. It is connection-oriented and performs error retransmission.
- C. It is unreliable and does not guarantee the delivery of information.Correct
- D. It operates at the physical layer to avoid packet collisions.
Explanation. The textbook states that the Internet Protocol (IP) is an unreliable protocol because it delivers packets without guaranteeing successful reception.
