SIT202 Computer Networks Trimester 2

Running head: SIT202 COMPUTER NETWORKS TRIMESTER 2
SIT202 Computer Networks Trimester 2
Name of the Student
Name of the University
Author’s Note

1
SIT202 COMPUTER NETWORKS TRIMESTER 2
Answer to Question 1 (Chapter 3)
1. What is the bit rate?
The processing and transfer speed rate of data is referred to as the bit rate and seconds is
used for measuring it. It can range from bps for the small values and reach to kbps or mbps. It is
also known as data rate. For digital telecommunication or networking the bit rate is measured in
second for the data passing through the communication network (Hayes, 2017). In case of
multimedia packets the bitrate is calculated as number of bits that are used per unit of playback
time. The encoding of the audio or video file affects the size of multimedia and its quality of
output
Thus, Bitrate = Amount of date / Time
2. If the number of signal level is 8 and the bandwidth is 3 MHz, what is the bit rate?
The calculation of bit rate is given below:
2 * 3 * log2(8) = 3 mbps
3. Suppose that the signal-to-noise ratio (SNR) is 6 dB. What is the capacity (in bits per second)
if the bandwidth is 3 MHz?
For the calculation of the capacity of the channel the following formula is used:
Signal to Noise Ration SNRdb = 10log10SNR
 SNR = 10SNRdb/10
 SNR = 10.6
 3.9810

2
SIT202 COMPUTER NETWORKS TRIMESTER 2
C = B log2 (1+SNR)
= 3*106 * log23.9810
= 3* 106 * 1.993
= 6 Mbps
4. Discuss the difference between the data rate and the capacity (e.g., answer why they are
different?)
The data rate and capacity differs from each other and the reason for its difference is give
below:
The rate of transferring data between the devices connected in the network represents the
data rate and the unit used for measuring the rate is mbps.
The maximum rate of transmission of data between the channels of communication is
known as the capacity. It differs from data rate because it has lower or upper limits of
transmission.
Answer to Question 2 (Chapter 6, 7, 8):
1. Explain the purposes of multiplexing and demultiplexing?
Multiplexing is used for combining the multiple data stream arriving from different
sources and transmitting it over a single data stream or channel. The multiplexing can be of two
types i.e. Time division multiplexing and frequency division multiplexing. A single channel non
overlapped time slots are used for the time division multiplexing and the data streams coming
from different sources are divided into equal sized units for interleaving it successively into the