This document contains information about a student named Jinat Afroz taking the course "Data Communication" in the spring 2021 semester. It provides details of the student's ID, program, course code, batch, campus, teacher, deadline and submission dates. It then answers questions about various topics in data communication including definitions of data communication, networks, PAN, nodes, LAN, MAC address, NIC, IP address, ports, network devices, switches, bits and bytes, differences between networking devices, bridges, repeaters and more.

1. Name: Jinat Afroz
Id: 19150025540
Semester: Spring 2021
Program: CSE (Eve)
Course Title: Data Communication
Course Code: CSE 313
Batch: 50th
Campus: City Campus
Teacher’s Name: Pranab Bandhu Nath
DeadlineDate: 07-05-2021
Submission Date: 21-05-2021
Question to Answer:
What is Data Communication?
 Data Communicationis the exchange of data (in the form
of o s and 1s) between two devices via some form of
transmission media (such as a wire cable). Data
Communicationis considered local if the communicating
devices are in the same buildingor a similarly restricted

2. geographicalarea. It is considered remote if the devices
are further apart.
What is Network?
 A network is a collectionof computers, servers,
mainframes, network devices, peripherals, or other
devices connected to one another to allow the sharing of
data. An example of a network is the Internet, which
connects millionsof peopleall over the world. To the right
is an example image of a home network with multiple
computers and other network devices all connected.
What is difference between Data Communicationand
Network?
Data Communication:When we communicate, we are sharing
information.This sharing can be localor remote. Between
individuals,localcommunicationusually occurs face to face
while remote communicationtakes place over distance.
Both analogand digital data can be transferred through mainly
these two processes.
Analog data is continuousin nature while digitaldata discrete
in nature.
Network: A computer network is a group of computer systems
and other computing hardware devices that are linkedthrough
the communicationchannels. A computer Network enables file

3. sharing across the network. It helps the web information to
traverse more easily and software and operating systems on
remote systems. Based on the area of Networking, Computer
Networks are of several types.
What is PAN?
 A Personal Area Network is a computer network organized
around an individual personal.It generally consists of a
mobile computer, a cell phone or personal digital
assistant. PAN enables the communicationamong these
devices. It can be used for communicationamong personal
devices themselves for connecting to a digitallevel
network and internet. The PANs can be constructed
wireless or cables.
What is Node?
 Can be any communicationdevice-PC, Smart Phone,
Router, gateway. Can be either source destination, or
intermediary. Each node on a network is identifiedby
uniquelogical address-IP address on TCP/IP. Node connect
to the network through its interface.
What is LAN?
 A LAN is a local area network and is defined as all in the
same broadcast domain.It works within campus or
buildingof up to 5lm. Its speed 10 mbps to 100mbps.

4. LAN: Local Area Network (only 5000 devices of network
connected up to 1km area).
PAN: Personal Area Network. (10km distance)
MAN: MetropolitanArea Network. (up to 10km Distance).
WAN: Wide Area Network.
What is MAC Address?
 The MediaAccess Control (MAC) address is just as
important as the IP Address. The MAC Address is a unique
value associated with the network adapterNIC. MAC
address is known as the hardware address or physical
address. They uniquelyidentifythe adapteron the LAN.
What is NIC?
 A NIC or Network Interface Card is a circuit board or chip,
which allows the computer to communicate with other
computers on a Network. Networks transmit data is serial
format to and computer communicateswith paralleldata.
NIC takes care of serial to parallelconversion and vice

5. Versa.
What is IP Address?
 An IP ADDRESS (or Internet Protocol address) is an address
used to uniquelyidentify a device on an IP network. The
address to make up of 32 binary bits which can be divisible
into a network portion and host portionwith the help of a
subnet mask. The 32 binary bitsare broken into four
octets
(1 octet=8bits). Each octet is converted to decimal and
separated by a period (dot). For this reason, IP address is said
to be expressed in dotted decimal format.
Types of Address:
Two types:
1. Physical Address: The physical address, also known as
the link address, is the address of a node as defined by its
LAN or WAN. It is included in the frame used by the data
link layer. It is the lowest-level address. The size and
format of these addresses vary depending on the network.
For example, Ethernet uses a 6-byte (48-bit) physical
address that is imprinted on the network interface card
(NIC).Most local area networks use a 48-bit (6-byte)
physical address written as 12 hexadecimal digits; every
byte (2 hexadecimal digits) is separated by a colon, as
shown below.

6. 2. Logical Address: Logical addresses are necessary for
universal communications that are independent of
underlying physical networks. Physical addresses are not
adequate in an internetwork environment where different
networks can have different address formats. A universal
addressing system is needed in which each host can be
identified uniquely, regard less of the underlying physical
network. The logical addresses are designed for this
purpose. A logical address in the Internet is currently a 32-
bit address that can uniquely define a host connected to
the Internet. No two publicly addressed and visible hosts
on the Internet can have the same IP address.
What is port?
 In computer hardware, a ‘port’ serves as an interface
between the computer and other computers peripheral
devices. Physically, a port is a specialized outlet a piece of
equipment to which a play or cable connects.
Electronicallythe several conductors making up the outlet
provide, single transfer devices. The term ‘port’ derived
from a Latin word ’portal’ (gate, entrance, door).

7. FIG: PORT
Computer Network Devices:
 Hub: A hub is basicallya multiport repeater. A hub
connects multiplewires coming from different branches,
for example, the connector in star topology which
connects different stations. Hubs cannot filter data, so
data packets are sent to all connected devices. In other
words, collisiondomain of allhosts connected through
Hub remains one. Also, they do not have the intelligence

8. to find out best path for data packets which leads to
inefficiencies and wastage.
 Switch: A switch is a multiport bridge with a buffer and a
design that can boost its efficiency (a large number of
ports imply less traffic) and performance. A switch is a
data link layer device. The switch can perform error
checking before forwarding data that makes it very
efficient as it does not forward packets that have errors
and forward good packets selectively to correct port only.
In other words, switch divides collisiondomainof hosts,
but broadcast domain remainssame.
 Router: A router is a device like a switch that routes data
packets based on their IP addresses. Router is mainly a
Network Layer device. Routers normally connect LANs and
WANs together and have a dynamicallyupdatingrouting
table based on which they make decisionson routing the
data packets. Router divide broadcast domainsof hosts
connected through it.

9. Fig: Different Device
What is switch?
 A network switch is a computer networking device, that
is used to connect multiplecomputer together within on
Local Area Network (LAN). In other words, it is capable
to determine specific source and destination.
Technically,network switch operate at layer two (Data
Link Layer) of the OSI model. The network switch
commonly refers to routes data at the data link layer of
the OSI model.

10. What is Bit and Byte?
 Bit: A bit is the basic unit in computer information and
has only two different values, generally defined as a 0
and 1. These values can be interpreted as on or off, yes
or no, true or false etc. It just dependson the binary
code.
 Byte: A byte is just 8bits and is the smallest unit of
memory that can be addressed in many computer
systems. The following list shows the relationship
between all at the different unitsof data.
0 (off) or 1 (on) = 1Bit
8Bits = 1 Byte
1024 Byte = 1Kilobyte
1024 Kilobytes = 1 Megabyte
1024 Megabytes = 1 Gigabyte
1024 Gigabyte = 1Terabyte
1024 Terabytes = 1 Pet byte
1024 Pet bytes = 1 Exabyte
1024 Exabyte’s = 1 Zetta byte

11. What is different between Hub, Switch, Router, Bridge and
Repeater?
Bridge:
1. Bridge operates in data link layer of OSI Model.
2. Bridge is use to connect two different LAN Segment.
3. Bridge transmits data in the form frames.
4. Bridge reads the MAC Address of a device.
5. Bridge has only two parts.
6. Bridge does not use any routing table for sending data.
Router:
1. Routers operate in network layer of OSI Model.
2. Router is use to connect the LAN and WAN.
3. Router transmits data in the form of packets.
4. Router reads the IP Address to a device.
5. Router has more ports compare to bridge.
6. Router uses routing table for sending data.
Switch:
1. A switch is a fundamentalpiece of hardware that allows
network devices to communicate with each other.
2. Switch receives information from source and dispatches
that informationto the intended destinationonly.
3. Switch receive are typicallya layer 2 device of the OSI
Model.

12. 4. They analyzetraffic packets as they arrive from the
many machines and send the packets to the intended
MAC Address.
Repeater:
1. Repeater operates at physicallayer of OSI Model.
2. Repeater do not understand computer frame.
3. Repeater is not able to recognize the destination
address.
4. Repeater expandsthe limit of the signals in the
network.
5. Repeater cannot perform packets filtering.
Hub:
1. Hub is known as the simplest amongst this device.
2. In general, hub is the central part of a wheel where the
spokes come together.
3. It cannot filter data, data packets are sent to all connected
devices and there is no inefficiencies and wastage.
4. As a network product, a hub may include a group of
 Modem-cards: for dial in user.
 A gateway card: for connectionsto a localarea
network (LAN) and a connectionto a line.
5. Hubs are used on a small network where data
transmission is not very high.

13. What is Bridge?
 A network bridge is a that allowsus to create single
network from multiplenetworks. This function is
called network bridging or bridging logic. Bridging is
different from routing. Routing allowsmultiple
networks communicate independentlyand yet
remain separate.
What is Repeater?
 A repeater is a device that operates only at the
physical layer. A repeater can be used to increase the
length of the network by eliminatingthe effect of
attenuationon the signal. It connects two segment
off the same network, overcoming the distance
limitationsof the transmission media. A repeater
forwards every frame, it has no filtering capability.A
repeater is a regenerator, not an amplifier. Repeater
can connect segments that have segments that have
the same access method (CSMA/CD). Token passing
pollingetc.
 What is IP?
An IP address (abbreviationof Internet Protocol
address) is an identifier assigned to each computer
and other device (e.g. printer, router, mobile device
etc) connected to a TCP/IP network that is used
locate and identify the node in communicationswith

14. other on the network IP address are usually written
and displayedin human-readablenotations,such as
172.16.254.1 in IPv4 and in IPv6
2001.odb8.85a3.0000.0000.8a2e.0370.7334
Class of IP:
Class A : 1-126 (10provite IP)
Class B : 128-191 (127 pin loopback address)[172 provid
IP)
Class C : 192-223
Class D : 224-239
Class E : 240-255
What is Loopback Address?
IPv4 loopbackaddress are the addresses in the range of
127.0.0.1 to 127.255.255.255 loopbackaddress is used by
hosts to direct traffic to themselves.
 If a host sends a packet with a loopback address as
the destinationIP address, the packet will be
delivered to itself.
 This address cannot be assigned to any Internet host.
The loopbackaddress is mainly used for testing.
 To test the TCO/IP configuration of a host.
 Used by developersto test network application.

15. Types of IP:
IPv4: IPv4 was the first version of IP. It was deployed for production in
the ARPANET in 1983. Today it is most widely used IP version. It is
used to identify devices on a network using an addressing system.
The IPv4 uses a 32-bit address scheme allowing to store 2^32 addresses
which is more than 4 billion addresses. Till date, it is considered the
primary Internet Protocol and carries 94% of Internet traffic.
Features of IPv4
 Connectionless Protocol
 Allow creating a simple virtual communication layer over
diversified devices
 It requires less memory, and ease of remembering addresses
 Already supported protocol by millions of devices
 Offers video libraries and conferences
IPv6: It is the most recent version of the Internet Protocol. Internet
Engineer Taskforce initiated it in early 1994. The design and
development of that suite is now called IPv6. This new IP address
version is being deployed to fulfill the need for more Internet
addresses. It was aimed to resolve issues which are associated with
IPv4. With 128-bit address space, it allows 340 undecillion unique
address space. IPv6 also called IPng (Internet Protocol next
generation).
Features of IPv6
 Hierarchical addressing and routing infrastructure
 Stateful and Stateless configuration
 Support for quality of service (QoS)
 An ideal protocol for neighboring node interaction

16. OSI Model
[APSTNDP]
Software/Upper layer
Heart of OSI
Hardware/Lower layer
[ATNP]
Application
Presentation
Session
Transport
Network
Data Link
Physical
Application
Presentation
Session
Transport
Network
Data Link
Physical