This document is an assignment submission for a computer networks course. It provides an overview of the history of computer networks from the 18th to 21st centuries. It then discusses key early networks like ARPANET and how it was developed by the US Defense Department to link research institutions without a central point of failure. The document also defines different types of computer networks like PAN, LAN, MAN, and WAN and provides examples of common network hardware, software, and cabling used in each type.

1. Assignment 1
Course tittle:computer network
Course code: CSE 318
Submitted to:
pranab Bandhu nath
senior Lecturer, Department of CSE
City university, Dhaka
Submitted by
Md parvez
Id: 184902610
Bsc in cse(day)
Batch :49th
1: Computer netweork history (18th
to 21th)
18th
centuries( watts , stream engine,optical telegram ,electric buttery)
19th
centuries ( Telagraph, telephone,electric buttery)
20th
centuries (radio , television,pc , computer )
21th centuries (sateliters , fiver optics)
2:ARPHANET: Advanced Research Projects Agency Network (ARPANET)

2. • U.S. Defense Department, funded the development of the Advanced Research
Projects Agency Network (ARPANET) in the late 1960s. Its initial purpose was to
link computers at Pentagon-funded research institutions over telephone lines
• At the height of the Cold War, military commanders were seeking a computer
communications system without a central core, with no headquarters or base of
operations that could be attacked and destroyed by enemies thus blacking out
the entire network in one fell swoop.
• Defense Department put out a call for competitive bids to build the network,
and in January 1969 Bolt, Beranek, and Newman (BBN) of Cambridge,
Massachusetts, won the $1 million contrac
What is Computer Network?
• A computer network is a set of computers connected together for the purpose
of sharing resources. The most common resource shared today is connection to
the Internet. Other shared resources can include a printer or a file server. The
Internet itself can be considered a computer network
Goals of Computer Network:
• Sharing Resources from one Computer to another Computer over a network
• Performance by measuring the speed of data transmission with number of
users, connectivity and the software used
• Reliability makes easy to use an alternative source for data communication in
case of hardware failure or connectivity issues
• Scalability increases the system performance by adding more processors

3. • Security is the main characteristics of Computer network where you can take
necessary steps for protecting your data from unauthorized access
Computer Network Types:
• PAN(Personal Area Network)
• LAN(Local Area Network)
• MAN(Metropolitan Area Network)
• WAN(Wide Area Network)
PAN(Personal Area Network)
• Personal Area Network covers an area of 10 meters. • PAN includes mobile
devices, tablet, and laptop. • Thomas Zimmerman was the first research scientist
to bring the idea of the Personal Area Network.
LAN(Local Area Network)
• Local Area Network is a group of computers connected to each other in a small
area such as school, laboratory, home, and office building. • It is a network which
consists of less than 5000 interconnected devices across several buildings. • Data
of all network users can be stored on a single hard disk of the server computer. •
Local Area Network provides higher security
MAN(Metropolitan Area Network)
• Metropolitan Area Network or MAN is consisting of a computer network across
an entire city, college campus, or a small region • The most widely used protocols
in MAN are RS-232, Frame Relay, ATM, ISDN, OC-3, ADSL, etc. • It offers fast
communication using high-speed carriers, like fiber optic cables
WAN(Wide Area Network)

4. • WAN network system could be a connection of a LAN which connects with other
LAN's using telephone lines and radio waves. It is mostly limited to an enterprise
or an organization. • A Wide Area Network is widely used in the field of Business,
government, and education. • The software files will be shared among all the
users; therefore, all can access to the latest files.
Hardware Equipment example
Nic Server , clint , peer transmission ,medum , router , Bridge , hub , switch ,
gateway , reapeter
Software Example
Network , opersting system , protocol , switch , (tcp/ip/osi)
Cable and cannectors
Twisted pair cable , co-oxial cable , fiver optic cable
Hub
A hub is a device that allows multiple computers to communicate with each other
over a network. If we 4 pc connect so we use hub..for 4 pc connection using
hub.and hub generally used to connect computer in a LAN . and hub is physical
networking device which is used to connect multiple devices in a network.
Switch
Switch are connectivity point of and Ethernet network. And switch are detect one
device and it is the data;link 2 layer device . These are small devices that can
receive data from multiple input ports and send
Router

5. A router receives and sends data on computer networks. A wireless router
connects directly to a modem by a cable. This allows it to receive information
from — and transmit information to — the internet. The router then creates and
communicates with your home Wi-Fi network using built-in antennas. As a result,
all of the devices on your home network have internet access
Bridge
Bridge is a feltering method and doing feltering . bridge have a 2 port ,and bridge
is computer network .Bridge connects two or more different LANs that has a
similar protocol and provides communication between the devices (nodes) in
them
Repeater
Repeater is a powerful network device which is used to regenerate the signals,
when they travel over a longer distance. Repeater using from routerif clint far
then we use repeater .out of 1 km
Repeater are used to extend transmissions so that the signal can cover longer
distances or be received on the other side of an obstruction
Gateway
A gateway is a network node that forms a passage between two networks
operating with different transmission protocols .gateway is a piece of networking
hardware or software used in telecommunications for telecommunications
network.