Data Communication and Networks Short Questions With Answers Series 2 Chapter 1
In this series we will provide ten more questions regarding Data Communication. Students can read these questions and memorize. After some time we will conduct an online test for the students where they can also check how much they learn from this series.
Q.11. Differentiate between analog and digital signal. Which is popular?
Ans: Analog signals can have an infinite number of values in a range whereas digital signals can have only a limited number of values. Digital signals are popular because they provide lower error rates, higher transmission speed and quality voice transmission.
Q.12. What do you know about parallel data transmission?
Ans: A method of transmission in which groups of bits are sent at same time over multiple wires is called parallel transmission. It is usually unidirectional. Each bit is transmitted over a separate line. Data transmission between computer and printer is a parallel transmission.
Q.13. Differentiate between serial and parallel transmission?
Ans: Parallel transmission is faster because all bits are sent at the same time. Serial transmission is slower than parallel transmission because data is sent sequentially one bit at a time. Each individual bit of information travels along its own communication path.
Q.14. Describe Asynchronous data transmission?
Ans: In asynchronous transmission, data is transmitted character by character. There are irregular gaps between characters. It uses flow control instead of clock to synchronize data between source and destination. It is cheaper because data is not saved before it is sent.
Q.15. Describe Synchronous data transmission?
Ans: In synchronous mode, saved data is transmitted block by block. Each block may consist of many characters. It uses a clock to control the timing of bits being sent. Synchronous transmission is much faster than asynchronous because there is no gap between characters.
Q.16. How does asynchronous transmission take place?
Ans: In asynchronous transmission, data is transmitted character by character. It uses a special start signal. A start bit has a value of 0. The value of 0 indicates that a character is about to be transferred. It alerts the receiver and it gets ready to receive the character. If start bit has a value 1, it indicates that the line is idle.
Q.17. Compare asynchronous and synchronous transmission?
Ans: In asynchronous transmission, data is transmitted one character at a time. The sender and receiver are not synchronized with each other. Synchronous transmission sends a block of characters at a time. It allows sender and receiver to be synchronized with each other. Synchronous transmission is typically more efficient than asynchronous communications.
Q.18. Define a computer network?
Ans: A computer network consists of two or more computers that are connected together to share information and resources. The computers in network are connected together through communication media. The computers in the network can be in the same room, building or at different places.
Q.19. What are the criteria necessary for an effective and efficient network?
Ans: The criteria necessary for an effective and efficient network include performance, reliability and security. The performance can be measured in many ways such as transmit time and response time. The reliability is measured by frequency of failure, the time it takes a link to recover from a failure and the network’s robustness. The security issues include protecting data from unauthorized access and viruses.
Q.20. Name the factors that affect the performance of the network?
Ans: The factors that affect the performance of the network include number of users, type of transmission medium, hardware and software.
Q.21. How the computers in network are connected?
Ans: The computers in the network are connected together through communication media. The communication media can be a physical cable or a wireless connection.
