Short Question And Answer Computer Network Set-2

1. What do you mean by Automatic Repeat Request (ARQ)?
ARQ means retransmission of data in three cases:

  • Damaged Frame
  • Lost Frame
  • Lost Acknowledge

2. What are the responsibilities of Data Link Layer?
The Data Link Layer transforms the physical layer, a raw transmission facility, to a reliable link and is responsible for node-node delivery.

  • Framing
  • Physical Addressing
  • Flow Control
  • Error Control
  • Access Control

3. What are the three protocols used for noisy channels?
The three protocols used for noisy channels

  1. Stop – and – Wait ARQ
  2. Go – back – N ARQ
  3. Selective Repeat ARQ

4. What is CSMA/CD?
Carrier Sense Multiple Access with Collision Detection is a protocol used to sense whether a medium is busy before transmission and it also has the ability to detect whether the packets has collided with another

5. What are the various types of connecting devices?
There are five types of connecting devices

  1. Repeaters
  2. Hubs
  3. Bridges
  4. Routers
  5. Switches.

6. Define Flow control
It refers to a set of procedures used to restrict the amount of data the sender can sent before waiting for an acknowledgement

7. What are the categories of Flow control?
The categories of Flow control are

  • Stop& wait
  • Sliding Window

8. Mention the disadvantages of stop& wait.

  • Inefficiency
  • Slow process

9. What are the functions of data link layer?
The functions of data link layer are

  •  Flow control
  •  Error control

10. Define Link Discipline
It coordinates the link system. It determines which device can send and when it can send.

11. What do you mean by polling?
When the primary device is ready to receive data, it asks the secondary to send data. This is called polling.

12.What are the various controlled access methods?
The various controlled access methods are

  1. Reservation
  2. Token passing
  3. Polling

13 What are the various Random access methods?\
The various Random access methods are

  • Slotted ALOHA
  • CSMA

14. Define Piconet
A Bluetooth network is called Piconet .It can have up to eight stations one of which is called the master and the rest are called slaves,

15. What is the frequency range of Bluetooth devices?
The frequency range of Bluetooth device is 2.4 GHZ

16. What is the need of connecting devices?
To connect LANs or segments of LAN we use connecting devices. These devices can operate in different layers of internet model.

17. What type of address a data link layer is using?
The data link layer is using a physical address

18. What do you mean by Backbone networks?
It allows several LANs to be connected. The architecture used are Star and Bus

19. What is the need of frame relay?
It is a Virtual circuit wide area network that was designed to respond to demands for a new type of WAN.

20. What is the maximum length of a datagram?
The maximum length of a datagram is 65,535 bytes.