# Data Communication

## Chemical Weapons attack, India-Bangladesh ties: Time for golden period, Current Affairs – 6th April 2017

Chemical Weapons attack Introduction Syrian Crisis has been long drawn and has seen humanitarian crisis of large scale. The recent chemical attacks add to the wounds and fears of people of the region. Syria has been a playground for global geo-politics with regime and rebels supported [...]

## Describe the various modes of data transmission. Or Explain the following with the help of examples – (i) Simplex (ii) Half duplex ( iii) Full duplex.

Ans. Data communications links are configured to fulfill the particular needs for a given system. In the simplest link, it contains a single primary and a single secondary station connected to node end points of the link. The primary station originates the communication link and maintains control [...]

## Give tile difference between asynchronous and synchronous transmission. Or Differentiate between synchronous and asynchronous transmission. Or Compare the various asynchronous and synchronous transmission techniques.

Ans- The comparison between asynchronous and synchronous Transmission techniques is as follows-

## Consider the same transmission scheme and that data are to be Transmitted at a rate of 10,000 bps. If there is a drift between the clock of Transmitted and receiver of 7 per cent (receiver’s clock is faster than transmitter’s clock). Explain what will happened ?

Ans-   Since the transmitter clock and receiver clock are running on different speed, i.e., drift of 7% is observed. The received data will be in synchronization at start bit but due to accumulative error will go on increasing at a rate of?% per bit interval, the [...]

## Describe the asynchronous transmission control scheme with their frame structure. Explain how synchronization is achieved in it. Explain the framing error. Or Describe the asynchronous transmission control scheme with the frame structure. Or Explain the asynchronous transmission with their frame structure.

Ans. The asynchronous transmission is used to avoid the timing problem by not sending long, uninterrupted streams of bits. In this scheme, data is transmitted one character at a time, where each character is five to eight bits in length. Timing or synchronization must only be maintained [...]

## Explain the asynchronous transmission and synchronous transmission in brief. Or Compare the overhead in an asynchronous system versus a synchronous ssystem. How is the overhead partitioned in each ? Which is more efficient, in terms of the overhead to send several characters? Why.

Ans. Asynchronous Transmission- In the Asynchronous Transmission the timing of a signal is unimportant. Instead, information is received and translated by agreed-upon patterns. As long as those patterns are followed, the receiving device can retrieve the information without regard to the rhythm in which it is transmitted. Patterns [...]

## Differentiate between the serial transmission and parallel transmission.

Ans. The difference between the serial transmission and parallel transmission is given below -   S.No.    Parallel Transmission                  Serial Transmission (i)          This type of transmission                In this transmission, all the bits permits the transmission of a         are transmitted [...]

## What is data transmission ? Explain the parallel transmission and serial transmission. Or Write short notes on parallel and serial transmissions.

Ans- There is always a need to exchange data, commands and other control information between a computer and its terminals or between two computers. This information is in the form of bits. Data transmission refers to movement of the bits over some physical medium connecting two or [...]

## Discuss and explain the following- (i) Throughput (ii) Delay (iii) Bandwidth delay product.

Ans. (i) Throughput- The throughput-  is the measurement of how fast data can pass through a point. In other words, if we consider any point in the transmission medium as a wall through which bits pass. throughput is the number of bits that can pass this wall [...]

## State the Shannon’s theorem regarding channel capacity. Explain the significance of same. Or Explain what is Shannon capacity. Also discuss the trade off between bandwidth and cltunnel capacity. Or Explain the Shannon’s theorem.

Ans  Shannon 's theorem is related with the rate of information transmission over a communication channel.The term communication channel covers all the features and component parts of the transmission system which introduce noise or limit the bandwidth,. According to Shannon's theorem, it is possible, in principle, to devise [...]

## Define shannon and Nyquist channel capacity. Or Discuss Nyquist bit rate and also explain the shannon theorem for capacity.

Ans. A very important consideration in data communications how fast we can send data. in bits per second, over a channel. Data rate depends on three factors - (i) The band width available (ii) The level of the signals we use (iii) The quality of the channel (the level [...]

## Explain baseband and broadband transmission. discuss attenuation, distortion and noise.

ans. baseband transmission- when a digital signal is transmitted on the medium using one of the signal codes like NRZ, RZ Manchester biphase-M code etc. is called baseband transmission.baseband transmission is limited to low data rates because at high data rates, significant frequency components [...]