Components of Network,Network, personal computer

 

 Network: -

A network is an interconnected collection of autonomous computers. Two
computers defined as interconnected if they are capable to interchange information. The autonomous computer means that no computer on the network can start, stop or control another computer. The jobs are allotted in the network without users' intervention.

 Components of Network: -

A basic network is made up of the following hardware.

₀  Server

• Workstations / Nodes •

Interface Cards

•  Cabling system

 • Shared resources and peripherals

 Server:-

The server runs the network operating system and offers network services to
workstations. These services include the file storage, user management, security, common network commands, system manager commands and much more.

Nodes: -

When a computer is attached to a network, it becomes a node on the network. It
is sometimes referred as workstation. A node can be DOS-based PC or Windows 95/ 2000-based PC.

 Interface Card:-

 Each computer to be attached to the network requires network interface card. The
interface card must match the type of network being used. The network cable attaches to the interface card for networking.

 Cabling System:-

 The network cabling system is the wire used to connect the server together with
nodes.

 Shared Resources and Peripherals: -

Shared resources include the storage devices attached to the server, optical disk

drives, printers, plotters and other equipment that can be used by any one on the network. Windows 2000 NT OS includes commands to share printers attached not only to the server but to node as well.

 Types of Networks:-

 There are two types of networks 

•   Local Area Network (LAN)

•  Wide Area Network (WAN)

Following hardware are used in both types of networks:

 MODEM:-

 It is a device that converts the digital signals generated by computer to the
modulated analog signals required for transmission onwards and transforms incoming analog signals to their digital equivalent. Modems are frequently being used to exchange programs and data with other computers or on-line information services

Hub:-

 Hubs are commonly used to connect the segments i.e. nodes of a LAN. A hub
contains multiple ports. When a packet of information arrives at one port, it is copied to the other ports so that all the nodes can see all packets.

 Switch:-

It is a device like hub and it filters and forwards packets between LAN nodes. 

Router: -

The information is transferred in the form of packets in the networks such as
Internet. Therefore, such networks are called packet-switching networks. A router is a device that examines each data packet it receives, and then decides which way to send it to onward towards its destination.

 Gateway:-

The gateway is used when data is translated between two data formats or
networks. The information is transferred in the form of packets. When packets arrive at a gateway, all information is stripped off to retranslate the information. It then re-packs the information in required format for the destination. 

VSAT:-

It stands for Very Small Aperture Terminal, VSAT is an earthbound station used
in satellite communications of data, voice and video signals, excluding broadcast television.

Definition of a Personal Computer:-

 A personal computer is a device, which computes the data or information in a very fast and efficient manner in a pre-defined fashion. The device refers to any piece of hardware.

 Purpose of Computers:-

                                                         There are three main purposes to use computers. 

1. To solve problems
 2. To control process
 3. To provide information

Block Diagram of Personal Computer:-

 

Some Well-known Brands of PCs: -

                                                                          IBM, HP, Zenith, Accer, Wipro, HCL, SpiceNet etc. are popular brands of personal computers.

 Components of a PC:-

 • Input Unit 
• Output Unit 
• Central Processing UnitDocuments

Input Units:-

An input device enables you to input information and commands into
computer. The most commonly used input devices are Keyboard and mouse. The
alternate input devices are microphones and scanners. The storage input devices
are Floppy Disk Drive (FDD), Hard Disk Drive (HDD), Cartridge/ Magnetic Tape
Drive (CTD/ MTD), and optical storage devices are CD-ROM/ DVD-ROM
Drives etc.

Output Units:-

These are units or devices on which, computer prints or outputs the information or results. Some examples are:

                    Printers (Line printer, Dot matrix printer, Inkjet printer and Laser printer),
VDU i.e. Visual Display Unit (monitor or terminal screen), Floppy Disk Drive,
Hard Disk Drive and Cartridge/ Magnetic Tape Drives, Pen Drive and CDRW
(Compact Disc ReWritable) Drive etc.

Central Processing Unit:-

Central Processing Unit consists of three main units, i.e. Main Memory Unit, ALU and Control Unit.

i.e. Main Memory Unit, ALU and Control Unit.

The Main Memory Unit consists of two types of memories- volatile
memory (RAM- Random Access Memory) and non-volatile memory (ROM-Read
Only Memory). ROM is used to boot the system and RAM is working memory.
Booting means starting of computer. The contents of RAM lost when power fails.

 

           ALU, Arithmetic and Logic Unit, does the arithmetic calculations and
logical comparisons.

          The Control Unit controls the various resources and also enables smooth
execution of the program instructions.

Key Components of a Computer System:-

Hardware, Software, User and data are four key components of a computer system.

Some Computer related Terms:-

1. Hardware:-

It refers to physical computer equipment and associated devices.

2. Software:-

It is a collective term for the programs. Software is the tool to use hardware.
It controls and directs the activities of a computer or sets the instructions, which
direct the operation of the hardware.

3. Operating system:-

The software, which is responsible for all the operations of the system, is
known as an operating system. An operating system does over all supervision of
hardware and software. Some examples are:- MSDOS, Windows 98, Windows
2000, LINUX etc.

4. Processing:-

A computer system accepts the information or data through input unit,
processes it in the central processing unit and outputs the results on the output
unit. It is called as data processing or processing. Sometimes, it is also called as
Electronic Data Processing (EDP). The execution of a set of instructions or
operating system command or a computer program is called a process.

5. Motherboard:-

A motherboard is a hardware component on which processor, memory,
controller and all the connections are simulated. Various types of motherboards
are available in the market with some code numbers, e.g., INTEL- 815, 815E,
845, 845G, 845GV, 865G and 915 etc.

6.  Processor: -

It is the hardware for the processing of all input data and information. Some well known manufacturers of processors are :- INTEL, Cyrux, AMD, Motorolla etc. Some latest processors are :- Celeron, Pentium, Xeon, AMD etc. The processors are also available in series with numbers like Pentium- 80286, 80386,80486, P-I, P-II, P-III and P-IV etc.

7. SIMM:-

Single In-line Memory Module. The Random Access Memory consists of
memory module chips. Each memory chip module is called a SIMM. These chips are coming in 64MB, 128MB and in its multiple.