Computer Networks Mid - I, September - 2014

1.The method of communication in which transmission takes place in both directions, but only in one direction at a time is called
  • Simplex
  • Four wire circuit
  • Full duplex
  • Half duplex
Answer: D
2.In _____ topology, every device has a dedicated point-to point link to every other device
  • Ring
  • Star
  • Bus
  • Mesh
Answer: D
3.The presentation layer is responsible for
  • Flow control
  • Error control
  • Translation
  • Reassembly
Answer: C
4.Manchester code is a
  • Bi-polar code
  • Non return to zero code
  • Polar code
  • None of the above
Answer: C
5.__________ handle communication between offices.
  • Loops
  • Trunks
  • Switches
  • None of the above
Answer: B
6.BNC connector is used in
  • Coaxial cable
  • Twisted pair
  • Fiber optics
  • Infrared
Answer: A
7._____ refers to a set of procedures used to restrict the amount of data that the sender can send before waiting for acknowledgement.
  • Flow control
  • Error Control
  • Both A & B
  • None
Answer: A
8.______________ protocol is needed for bringing lines up, testing them, negotiation option and bringing them down
  • Point to point protocol
  • Network control protocol
  • Sliding window protocol
  • Link control protocol
Answer: D
9.______________ does not require global time synchronization
  • Pure aloha
  • Slotted aloha
  • CSMA
  • CSMA with collision detection
Answer: A
10.Number of channels used for transmission in CDMA
  • 1
  • 2
  • 3
  • 4
Answer: A
11..______________ is a set of devices(often referred to as nodes) connected by communication links.
Answer: Network
12.______________ protocol provides full transport layer services to applications.
Answer: TCP
13.________________ refers to the amount of time,in seconds,a signal needs to complete 1 cycle.
Answer: period
14.Transmission media lie below the _____________________ layer.
Answer: physical
15._______________________ is a cable that accepts and transports signals in the form of light.
Answer: Optical fiber
16.The technique in which the data link layer automatically stuff bit ‘0’ after five consecutive ‘1’s ________________.
Answer: Bit stuffing
17.______________ is a protocol in which, rather than discarding all the subsequent frames, following a damaged or lost frame, the reciever’s data link layer simply stores them in buffers.
Answer: Selective repeat
18.In pure ALOHA, channel utilization, expressed as throughput S, in terms of the offered load G is given by ____________ .
Answer: S = Ge - 2G
19.The 802.2 standard describes the ____________, which is the upper part of the data link layer.
Answer: Logical link layer
20.Ethernet uses __________ encoding.
Answer: Manchester