ENGINEERS ACADEMY Computer Networks Computer Network Basics | 1 QUESTION BANK 1. Segentation is done in 12. Session layer is used for (a) transport layer (b) network layer (a) dialogue control (b) traffic control (c) data link layer (d) physical layer (c) flow control (d) error control 2. Network layer activities are: 13. Network to network delivery is done on (a) logical addressing (b) port addressing (a) network layer (c) access control (d) all of these (b) transport layer 3. As the data packet moves from a lower layer to (c) application layer higher layer, the headers are (d) data link layer (a) added (b) removed 14. port number is (c) re-arranged (d) modified (a) process number 4. Hop-to-Hop delivery is related to (b) computer’s physical address (a) data link layer (b) network layer (c) both (a) and (b) (c) transport layer (d) all of these (d) none of these 5. process-to-process delivery is related to 15. the upper layers of the OSI model are in correct (a) data link layer (b) network layer order- (c) transport layer (d) all of these (a) session, application, presentation 6. synchronization of bits is done by (b) session, presentation, application (a) data link layer (b) network layer (c) session, application, presentation, physcial (c) transport alyer (d) none of these (d) application, presentation, session, physical 7. Which one of the following OSI layers performs 16. the lower layers of the OSI model are, in correct errror checking of data? order- (a) network (b) transport (a) physcial, system, netowrk, logical (c) data link (d) physical (b) physical, logical, netowrk, system 8. Flow control is the responsibility of (c) physical, transport, network, data link (a) data link layer (b) transport layer (d) physical data link, network, transport (c) both (a) and (b) (d) application layer 17. the Internet Protocol (IP) generally corresponds 9. Routing is done in to which OSI layer? (a) network layer (b) physical layer (a) network (layer three) (c) data link layer (d) transport layer (b) transport (layer four) 10. Which of the following address cannot be (c) data link (layer two) changed? (d) session (layer five) (a) hardware address (b) logical ddress 18. MTU stands for (c) both (a) and (b) (d) none of these (a) minimum transfer unit 11. Congestion control is done in (b) minimum transmission unit (a) MAC layer (b) data link layer (c) maximum transmission unit (c) transport layer (d) application layer (d) maximum transfer unit # 100-102, Ram Nagar, Bambala Puliya Email : info @ engineersacademy.org Pratap Nagar, Tonk Road, Jaipur-33 Website : www.engineersacademy.org Ph.: 0141-6540911, +91-8094441777 ENGINEERS ACADEMY 2 | Computer Network Basics Computer Science & IT 19. The part of OSI where one most commonly finds 28. Which layer of OSI model provides services data encryption, compression, and other encoding directly to user applications? for network communication is (a) application (b) presentation (a) application (layer seven) (c) session (d) transport (b) session (layer five) 29. the bottom layer of the OSI model is about (c) presentation (layer six) electrical and meachanical aspects of networking. (d) none of these What is the layer known as? 20. Which of these network devices belongs at the (a) transport (b) data link OSI physical layer (layer one)? (c) physcial (d) session (a) repeater (b) router 30. Which layer of the OSI model is responsible for (c) switch (d) bridge routing packets from one network to another? 21. which of these network devices belong at the (a) transport (b) network OSI data link layer (layer two)? (c) data link (d) physcial (a) router (b) bridge 31. What network topology implements at least two (c) VPN (d) none of these paths to and from each node? 22. Which of these network devices primarily (a) bus (b) ring functions at the OSI Netwcrk layer (layer 3)? (c) star (d) mesh (a) switch (b) gateway 32. What type of network topology is depicted by a (c) router (d) all of these single cable where devices connect using ‘T’ 23. In OSI, then term PDU stands for connectors? (a) private data unit (a) star (b) bus (b) protected data unit (c) ring (d) 10 base T (c) public data unit 33. The physical layer is responsible for the (d) protocol data unit transmission of____over the physical medium. 24. Which Protocol Data Unit (PDU) is employed at (a) packets (b) bits the Transport layer? (c) message (d) all of these (a) bits (b) frames 34. Which layer of the OSI dodel deals with physcial (c) packets (d) segments trasmission across a physical network? 25. Which Protocol Data Unit (PDU) is employed at (a) physical (b) data link the Network Layer? (c) network (d) transport (a) bits (b) frame 35. HTTP uses (c) packets (d) segments (a) TCP/IP protocol 26. What is the Protocol Data Unit (PUD) employed (b) UDP protocol at the Data Link Layer? (c) OSI protocol (a) bits (b) frames (d) SMTP protocol (c) packets (d) segments 36. Baud rate means 27. What is the Protocol Data Unit (PDU) employed (a) number of bits transmitted per unit time at the Physcial Layer (b) number of signal units per second to represent bits (a) bits (b) frames (c) number of pulse transmitted per unit time (c) packets (d) segments (d) number of bits received per unti time # 100-102, Ram Nagar, Bambala Puliya Email : info @ engineersacademy.org Pratap Nagar, Tonk Road, Jaipur-33 Website : www.engineersacademy.org Ph.: 0141-6540911, +91-8094441777 ENGINEERS ACADEMY Computer Networks Computer Network Basics | 3 38. Machester code is a (b) forward it to all ports except the port it came (a) non-return to zero code in from (b) polar code (c) hold it until the destination MAC address is discovered (c) bipolar code (d) block it (d) both (a) and (b) 44. A hub is a 38. How many characters per second (7 bits + 1 parity) can be transmitted over a 2400 bps line (a) router (b) bridge in case of synchronous and asynchronous transfer (c) repeater (d) all of these (1 stop and 1start bit) 45. Modulation and demodulation are done by (a) 300, 300 (b) 300, 240 (a) hub (b) modem (c) 250, 300 (d) 240, 300 (c) bridge (d) none of these 39. Which of the following options is not an useful 46. Which one of the following devices can be used property of Manchester line code for an Ethernet? to connect two LAN networks which use similar (a) continous energy protocols? (b) continuous clock transition (a) bridge (b) transceiver (c) no DC component (c) repeater (d) gateway (d) no signal change at a 1 to 0 transition 47. Which one is not true for repeater? 40. Which of the following statements best describes (a) A repeater connects segments of a LAN a hub? (b) A repeater has filtering capability (a) all connected systems are in the same (c) A repeater is a regenerator broadcast domain, but different collision (d) A repeater can’t act as an amplifier domains 48. If switches are used to replace hubs on a network, (b) all connected systems are in the same collision which of the following statements is true? domain, but different broadcast domains (a) the number of broadcast domains will increase (c) all connected systems are in the same (b) the number of collision domains will increase broadcast and collision domains (c) the number of collision domains will decrease (d) all connected systems are in their own broadcast and collision domains (d) The number of broadcast domains will decrease 41. At which layer of the OSI model does a switch exist? 49. What layer of the OSI model is designed to perform error detection functions? (a) physical (b) data link (a) physical (b) data link (c) network (d) seesion (c) network (d) transport 42. Every port on a switch defines a: 50. What layer of the OSI model is designed to (a) collision domain perform error recovery functions? (b) broadcast domain (a) physical (b) data link (c) broadcast and collision domain (c) network (d) transport (d) none of these 43. If a frame enters a bridge and the MAC address is not found in the MAC address table, what will the bridge do with the frame? (a) drop it # 100-102, Ram Nagar, Bambala Puliya Email : info @ engineersacademy.org Pratap Nagar, Tonk Road, Jaipur-33 Website : www.engineersacademy.org Ph.: 0141-6540911, +91-8094441777 ENGINEERS ACADEMY 4 | Computer Network Basics Computer Science & IT ANSWERS AND EXPLANATIONS 1. Ans. (a) 2. Ans. (a) 19. Ans. (c) Unlike some other layers of OSI, the presentation 3. Ans. (b) 4. Ans. (a) layer does not generally correspond to any 5. Ans. (c) 6. Ans. (d) particular network protocol. The presentation layer instead deals with data formats. For example, GIF 7. Ans. (c) 8. Ans. (c) (Graphic Interchange Format) and JPEG (Joint Photographic Experts Group) image formats fit into 9. Ans. (a) 10. Ans. (a) the presentation layer. 11. Ans. (c) 12. Ans. (a) 20. Ans. (a) 13. Ans. (a) 14. Ans. (a) Repeaters operate on the electrical signal of network communication. they regenerate signals by amplifying their strength and sometimes 15. Ans. (b) reconstructing to receover from distortion. An By convention, the “upper layers” of OSI consist active hub is perhaps the most common physical of session (layer five), presentation (layer six), and manifestation of a repeater. Being at the lowest application (layer seven). All other layers of OSI level of OSI, repeaters lack the intelligence of higher belong in the “lower layers” category, although level devices like bridges and routers. some references will claim that the transport layer 21.