DATA COMMUNICATION AND COMPUTER NETWORK (314318)

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DATA COMMUNICATION AND COMPUTER NETWORK

DCN Important Question UT 1 and 2

https://superprofile.bio/vp/data-communication-and-computer-networks-imp-questions

DCN Imp Questions and Answers for Semester Exam

https://superprofile.bio/vp/data-communication-and-computer-networks-imp-questions-432

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Course :- DATA COMMUNICATION AND COMPUTER NETWORK

Course Code :- 314318

Unit 1 :- Fundamentals of Data Communication and Computer Network

Unit 2 :- Transmission Media And Switching

Unit 3 :- Error Detection and Correction

Unit 4 :-  Network Communication Models

Unit 5 :-  Network Topologies And Network Devices

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Some Notes on Data Communication and Computer Network

• Message

Message is the information or data which is sent from sender to receiver. 

A message can be in many format. A message may be text, video, photo, or combination of them (multimedia).

• Sender 

Sender is a device such as mobile, host, camera or workstation which sends message to receiver via medium.

• Medium

When a sender sends a message to receiver it needs a path for travel to receiver. 

This path is known as Medium or channel.

• Receiver 

Receiver is a device such as host, mobile, cloud, or workstation which receives message and reproduce it.

• Protocol 

Protocol is defined as set of instruction followed by sender or receiver. 

Protocol governs the exchange of data in true sense. 

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DCN

 

1.       Define Burst Error.

 The term burst error means that 2 or more bits in the data unit have changed from 1 to 0 or from 0 to 1.

 

2.       List Error detection methods.

 Simple Parity Check , Repetition codes, Two Dimensional Parity Check , Checksum , Cyclic Redundancy Check (CRC).

1.       List IEEE Standards

Ans.

IEEE Standard	Description
IEEE 802	For LAN/MAN networks
IEEE 802.1	Standards for LAN/MAN management and bridging and remote media access control bridging.
IEEE 802.2	For Logical Link Control connectivity.
IEEE 802.3	Standards for CSMA/CD.
IEEE 802.4	Standards for the token passing bus access.
IEEE 802.5	For communication between LAN and MAN, and standard for token ring access.
IEEE 802.6	For exchanging information between systems
IEEE 802.7	For broadband LAN cable
IEEE 802.8	For Fiber-optic connection
IEEE 802.9	For integrated services, like voice-over video, etc.
IEEE 802.10	For security implementation in LAN/MAN
IEEE 802.11	For WiFi or Wireless Networking
IEEE 802.12	For demand Priority Access Method
IEEE 802.14	For Cable TV broadband communications
IEEE 802.15.2	For Bluetooth and Wifi co-existence mechanism
IEEE 802.15.4	For Wireless Sensors or Control Systems
IEEE 802.15.6	For Wireless Body Area Network, like Bluetooth low energy
IEEE 802.16	For Wireless Network connectivity, like WiMax
IEEE 802. 24	To facilitate collaboration and coordination among all IEEE 802 standards

 

2.       State features of fifth generation in mobiles.

Ans. 1) 5G provides significantly faster data rates compared to 4G.

2) 5G is faster than 4G, delivering internet speed up to 20 Gigabits-per-second (Gbps). 

3) Increased Bandwidth compared to 4G.

4) Low latency

5) Designed to be more energy efficient.

 

3.       Define the term topology. Give names of any 2 topology.

Ans. Topology refers to arrangement of nodes and connections, describing how the devices are physically or logically connected.

1)       Star Topology    2) Ring Topology    3)  Bus Topology

 

4.       State whether the bus is active or passive network. Justify your answer.

Ans. Bus is a passive network.

The bus topology is usually used when a network installation is small, simple or temporary. In bus network, the cable is just one or more wires, with no active electronics to amplify the signal or pass it along from computer to computer. State functions of Modem.

 

5.       Give two advantages of mesh topology.

Ans. 1) Mesh Topology provides high privacy and security. 2) In case of failure of a single device, the entire network didn’t break. 3) In case of failure of a single device, the entire network didn’t break.

 

6.     List any two components which work at Physical layer of OSI model.

Ans. power plugs, connectors, receivers, cable types, network cables (like Ethernet cables) and network interface cards (NICs),etc.

 

7.     State functions of Modem.

Ans. The main function of a modem is to convert the analog signals that come from telephone wire into a digital form.

 

8.     Define Data Encapsulation.  

Ans. Encapsulation is the process of adding additional information when data is traveling in an OSI or TCP/IP model. The information has been added on the sender’s side, from the Application layer to the Physical layer.

 

9.     List functions of physical layer.

Ans.

 State two names of protocol used at Data Link layer and Transport layer in OSI reference model.

Ans. At the Data Link layer, examples include Ethernet and Point-to-Point Protocol (PPP), while at the Transport layer, TCP (Transmission Control Protocol) and UDP (User Datagram Protocol) are commonly used.

 

2.     What is subnet masking?

Ans. Subnet masking is a method to divide an IP address into networks and host portions , it determines the which port of address represents the networks and which parts represents the devices within the network.

1.       Describe different types of errors in data communication.

Ans. Single bit error :- The term single bit error means that only one bit is changed in a data unit from 0 to 1 or 1 to 0. However , a single bit error can happen if we are having data transmission. For e.g., if 16 wires are used to sent 16 bit of word at a time and 1 of the wire is noisy, then one bit gets corrupted.

Burst Error :- The term burst error defines that two or more bits are changed in a data unit from 0 to 1 or 1 to 0. Note that burst error doesn’t mean that error occurs in consecutive bits. The length of burst error can be measured from the first corrupted bit to the last corrupted bit. Some bits in between may not be corrupted.

What is Switch ?

1. Switch is a network device that connects multiple computers to the network.

2. Switch is used to send private messages as well as there is no wasting of data.

3. Switch can easily identify which device is connected to which port by using MAC Address.

4. Switch is more intelligent than HUB.

5. Switch can direct transfer data from source device to destination device by using their MAC Addresses.

 

Advantages :-

1. It is generally used to unicast the message.

2. It provides more security than HUB. 

3. Switch supports full duplex data transmission mode.

4. It is used to send the data packets based on their MAC Address.

5. If one node fails then their will no effect on entire network.

Disadvantages :- 

1. It is more expensive.

2. If switch fails then entire network will be failed.

3. Difficult setup.