1. A hub is a hardware device that allows multiple devices to connect to a single computer port, such as a USB hub connecting multiple USB devices. A switch directs data packets within a local area network between connected devices. 2. A router connects different networks and forwards data packets to their intended IP addresses, allowing multiple devices to share an internet connection. 3. A network interface controller (NIC) is a hardware component that connects a computer to a computer network.

1. Name:Nowrin Jahan Siam
ID:1925102501
Hub: A hub refers to a hardware device that enables multiple devices or connections to
connect to a computer. An example is a USB hub that allows multiple USB devices to connect to
one computer, even though that computer may only have a few USB connections. Pictured is an
example of a USB hub. A hub does not need an IP address.
Switch: A switch is a high-speed device that receives incoming data packets and redirects
them to their destination on a local area network .
A LAN switch operates at the data link layer or the network layer of the OSI Model and, as such
it can support all types of packet protocols. The layer 2 switch is also sometimes called a
bridge.its function is to send frames containing data packets between nodes or segments of a
network.
switches are the traffic cops of a simple local area network. Switching establishes the trajectory
for the frames as the data units.

2. routing takes place at layer 3, there data gets sent between networks or from one network to
another.
Router:
A router is a device that connects two or more packet-switched networks . The function of
router is managing traffic between these networks by forwarding data packets to their
intended IP addresses, and allowing multiple devices to use the same Internet connection.

3. NIC CARD:
A network interface controller.NIC, also known as a network interface card, network adapter .
NIC card is a computer hardware component that connects a computer to a computer network.

4. IP ADRESS:
IP full form is internet protocol. IP address is a unique identifier. Any time that you use the
internet you’re requesting access to a specific online destination, and in return, information is
sent back to you. IP lays out the standards and rules for routing data and connecting to the
internet.
There are two types of IP addresses:
1. IPv4
2. IPv6
IPv4 and IPv6:
1. IPv4 is 32-Bit IP address and IPv6 is a 128-Bit IP address.
2. IPv4 is a numeric addressing method whereas IPv6 is an alphanumeric addressing method.
3. IPv4 binary bits are separated by a dot(.) and IPv6 binary bits are separated by a colon(:).
4. IPv4 supports broadcast. on the otherhand, IPv6 doesn’t support broadcast.
5. IPv4 has checksum fields while IPv6 doesn’t have checksum fields
6. When we compare IPv4 and IPv6, IPv4 supports VLSM (Variable Length Subnet Mask) and
IPv6 doesn’t support VLSM.
7. IPv4 uses ARP to map to MAC address whereas IPv6 uses NDP to map to MAC address.

5. IP ADDRESS RANGES:
Class A: 1-126
Class B: 128-191
Class C: 192-223
Class D: 224-239
Class E: 240-255
Transmission Mode In Computer Network:
Data Transmission mode defines the direction of the flow of information between two
communication devices.
The data transmission modes ar three types based on the direction of exchange of information:
1. Simplex
2. Half-Duplex
3. Full Duplex
1. Simplex
It is a one directional data transmissiom mode. The communication is unidirectional. A sender
can only send data but can not receive it.

7. This transmission mode is not so popular because we cannot perform two-way communication
between the sender and receiver in this mode. It is mainly used in the business field as in sales
that do not require any corresponding reply. It is similar to a one-way street.
For Example, Radio and TV transmission, keyboard etc.
Advantages of a Simplex transmission mode:
1. It utilizes the full capacity of the communication channel during data transmission.
2. It has no data traffic issues as it is one way transmission mode.
Disadvantages of a Simplex transmission mode:
1. It is unidirectional in nature having no inter-communication between devices.
2. There is no mechanism for information to be transmitted back to the sender.
2. Half-Duplex
Half-Duplex is the data transmission mode in which the data can flow in both directions but in
one direction at a time. Each station can both transmit and receive the data but not at the
same time.
This type of data transmission mode can be used in cases where there is no need for
communication in both directions at the same time. It can be used for error detection when the
sender does not send or the receiver does not receive the data properly. The data needs to be
transmitted again by the receiver.
For Example, Walkie-Talkie, Internet Browsers, etc.

8. Advantages of a half-duplex transmission mode:
1. It facilitates the optimum use of the communication channel.
2. It is a two-way communication.
Disadvantages of using a half-duplex transmission mode:
1. The two-way communication can not be performed at the same time.
2. Delay in transmission may occur as only one way communication can be possible at a
time.

9. 3. Full-Duplex
Full-Duplex is the data transmission mode in which the data can flow in both directions at the
same time. It is two-way communication in which both the stations can transmit and receive
the data simultaneously.
Full-Duplex mode has double bandwidth as compared to the half-duplex. Its capacity of the
channel is divided between the two directions of communication. This mode is used when
communication in both direction simultaneously.
Example, a Telephone Network
beacause the persons can talk and listen to each other simultaneously.

10. Advantages of a full-duplex transmission mode:
1. The two-way communication can be work simultaneously in both directions.
2. Fastest mode of communication between devices.
Disadvantages of a half-duplex transmission mode:
1. The capacity of the communication channel is divided into two parts.
2. It has improper channel bandwidth utilization because it’s a two way transmission.
Types Of Computer Network: