networking

                                Networking

  v What is Network?

    When two or more computers are connected to each other    by communication media for the purpose of data transferring is called network.

v Advantages of network: -

                              i.            It provides the facilities for sharing files.

                            ii.            It also provides sharing of resources.

                           iii.            By using it we can send any information fast.

                            iv.            It provides a low-cost data transfer facility.

 

v There are 3 types of network: -

                                         i.            LAN (Local area network).

                                       ii.            MAN (Metropolitan area network).

                                       iii.            WAN (Wide area network).

 

v Sender: - Sender is a person who sends the data with the help of a computer or another way.

v Receiver: - Receiver is a person who receives the data or information.

v Communication channel: - It is a medium by which we transfer our data from one system to another system.

    E.g: - Air, Wires, Waves etc.

v There are two types of communication channel: -

                                      i.            Wire.

                                      ii.            Wireless.

v Guided media: - It means direct connection from one computer to another computer by using wires.

E.g: - Ethernet cable, Co-axial cable, optical fibre cable etc.

Unguided media: - It means the connection between one computer to another computer with the help of waves.

E.g: - Radio wave (Bluetooth, wi-fi etc).

Microwave (Mobile, Satellite etc.)

Infrared (T.V remote control, motion sensor device etc.)

 

Server: - It is a centralized computer that has a huge storage capacity and very high processing speed.

àIt works as an intermediary between two or more computers that are connected in a network.

àA server can have many work station connected to it.

àIn other words, we can say that server is a centralized computer that accepts the requests from the client and responds to them.

 

v Work station: - It means the computer connected in a network.

àWork station is also known as a node (computer).

 

v NIU: - It stands for network interface unit.

àIt is a device attached to each node and also connected to the server.

àIt acts as a common interface to establish the connection between network computers to connect to an outside network.

àIt is also known as “Network Interface Card” (NIC).

àA unique physical address given to each NIC device by its manufacturer which is known as “Media Access Control” (MAC) address.

 

v Ethernet cable: - It is a data link technology that is used in LAN.

àIt was invented by an electrical engineer of the U.S who was named ‘Robert Metcalfe.

àCAT5, CAT6 are the types of Ethernet cable is connected to an Ethernet card of a computer.

àThe data transfer speed of this cable is 100-1000 Mbps.

àKeyboard, mouse etc are connected by using Ethernet cable.

 

v There are two types of Ethernet cable: -

01.        Straight through Ethernet cable: - It is used to connect the computer to the hub, switch or router.

àIt is a normal cable in which there are thin cables inside it in the same order of colour.

àThere are two standards in which the colour of such cables are arranged such as T-568A and T-568B.

 

02.        Ethernet crossover cable: - It is used to connect computing devices without connecting to the hub or switch.

àIt has different pinpoints on each side.

àIn this cable the main covering, the1^st wire with 3^rd wire and 2^nd wire with the 6^th wire is crossed from the left.

àRJ45 connectors are used to connect such cables sockets.

 

v Co-axial cable: - This cable transmits efficient current.

àIt consists of a single-line of conductor which is surrounded by an insulation layer.

àIt means transmission rate up to 100 Mbps and maintain bandwidth up to 400 Mhz.

àIt is available in two types such as 75-2 & 52-2 cable.

à‘75-2’ cable is used by the T.V operators & ’52-2’ cable is used in high-speed internet broadband network.

 

v Fiber optics cable: - It has more capacity for high-speed data transfer.

àIn this cable data’s are transferred in the form of electromagnetic waves.

àOne cable of such type can support over 30000 telephones lines at a time.

àIt is more expensive and fragile in nature.

àIts transmission rate is 10 Gbps and its bandwidth 20 GHz.

 

v Bluetooth: - It is wireless network connectivity that enables to connection of devices over the short-range.

àIt is unguided media.

àThe connectivity is based on radio waves technology.

àThe connection through Bluetooth consumes less power & the physical range of communication is up to 100 m.

àIt is applied at many places for bar code scanning, handset connection of input, output with PC.

àThe Bluetooth technology is developed and license by the Bluetooth special interest group (SIG).

àJEEE standard for Bluetooth is JEEE 802.15.1

 

v Wi-Fi: - It stands for wireless fidelity.

àIt is a network of wireless connection.

àIt is an unguided media by which we create a network.

àWi-Fi is established by radiofrequency like Bluetooth.

It is a strong connection.

àWi-Fi connection sometimes called “Wireless Ethernet”.

àIt is used to connect PC or PDA to the internet within a limited range.

àTo form a wireless computer network and Wi-Fi adaptor (802.11 b/g) is required with each computer.

àIt reduces the usage of spaces and cables.

 

v Wimax: - It stands for wireless interoperability for microwave access.

àIt is a type of technology of telecommunication technology that provides wireless transmission among connected nodes.

àIts range is within a 50 km radius from the base station.

àIts data transferred speed is 3 Mbps.

àIt can connect to the internet in long-range then Wi-Fi.

 

v Infrared: - It is a web by which computer of other devices transferred their data or files in short range.

àThe data travel from one device to another with the help of an infrared adaptor that is installed in PCs.

àIt is not used for creating network a connection like Wi-Fi, Wimax and Bluetooth.

  

v Types of network: -

àThere are three types of network such as:

 

1) LAN: - It stands for local area network.

àIt is a type of network in which two or more nodes are connected within a short range such as offices, departments, or manufacturing unit etc.

àWi-Fi cables are used to create land.

 

v Characteristics of LAN: -

                       i.            Its data transferred speed at the rate of 100-1000 Mbps between the nodes.

                    ii.            It is created by small organizations.

                 iii.            In LAN, there are high securities than MAN.

                  iv.            There is no specific traffic for its usage.

 

v MAN: - It stands for metropolitan area network.

àIt is a type of network which is created by the combination of two or more LAN.

àIt is used to connect one city to another city or to connect various government departments in the same city or also organizations.

àTo create this network we can use guided or unguided media.

 

v Characteristics of MAN: -

                                          i.            It covers more area than LAN but, smaller than WAN.

                                       ii.            It is surrounded within a single city or metropolitan area.

                                    iii.            It is mainly create for a large organization to connect all their branches in the same city.

                                     iv.            It has low security than LAN.

 

v WAN: - It stands for wide area network.

àIt is a type of network which is created by two or more LAN or MAN.

àIt covers large geographical area such as cities, states, countries or all over the world.

àIt is create for the purpose of sharing information over the world.

àTo create this network mainly uses unguided media i.e. satellite.

àWAN is also known as “Internet”.

 

v Characteristics of WAN: -

                                     i.            The data transfer speed is up to 150 mbps.

                                  ii.            It has less security data then LAN and MAN.

                               iii.            WAN between two or more networks are connected to “Gateway”.

 

v PAN: - It stands for personal area network.

àIt works in limited range within 10 meters.

àIt is an interconnection of several peripherals such as: laptop, smart-phone, printer and scanner.

àIt can be created by using guided media or unguided media.

àBluetooth, Infrared are common examples of PAN.

à    Bluetooth’s PAN are also known as piconets.

 

v CAN: - It stands for controller area network.

àIt is an ISO (International standard organization) certified method of communication between various electronic devices used lighting control, air conditioning, airbags, central looking in a vehicle etc.

 

v Network topology: - Topology refers to the physical layout of network connection between different workstation.

àIt shows the shape of network.

àThere are 6 types of network topology to design network as:

 

1)   Linear topology: - In this topology, all the nodes are connected in sequence by the helps of t-connector.

àIn this network, both ends of communication media are terminated and all nodes exist between them.

àIf one node fails, then entire network will be fail.

 

2)   Bus topology: - In this topology, each node are connected to the single common communication wire which is known as ‘BUS’

àAll the nodes are connected in simplest way.

 

3)   Star topology: - In this topology, all the nodes are connected with the help of centralized networking device which is known as ‘HUB’.

àIn this topology, if any nodes fails then entire network doesn’t fail and all the data or information are shared with the help of ‘hub’.

àIf centralized networking device fail then entire network will be destroyed.

 

4)   Ring topology: - In this topology, all the nodes are connected in the form of ring.

àEach node has two neighbours nodes and there is no any terminated points.

àData travel either clockwise or anti-clockwise direction between nodes.

 

5)   Tree topology: - This type of topology is created with the help of linear, bus and star topology.

àIn this network there are two or more networks are connected with the help of bus or cables.

àIt allows for expansion of internet.

 

6)   Mesh topology: - In this type of topology, each node has dedicated connection to another node.

àIf any node send messages to another node then it takes any path.

àIn this type of network, the data transferred speed will be high comparison to another topology.

 

v E-mail: - It stands for electronic mail.

àIt is the fastest, easiest and cheapest way of communication with people.

àWe can send or receive messages among persons across the world.

àTo use the e-mail facility we have required e-mail id and password.

 

v E-commerce: - It stands for electronic business or paperless business.

àBuying or selling products on internet is known as e-commerce.

 

v E-governance: - An administration of various government departments are connected through internet for exchanging information is called e-governance.

àAn government offices can directly gather information from anywhere quickly.

 

v E-banking: - The process of transfer money or take details of the account balance by sampling login into bank on internet is known as e- banking.

àWhen a customer or any person of bank can do banking transaction to internet without visiting the bank is known as e-banking.

 

v E-reservation: - The process of booking tickets of railways, airways etc with the help of internet for travelling is known as e-reservation.

 

v E-learning: - The process of learning through internet is known as e-learning.

 

àCAL (Computer aided learning) helps to provide information on various topics on internet.

 

v Internet: - It is an international network.

àIt is a network of networks.

àIt is also known as world wide area network.

àThere are various websites exist on the internet by which we obtained the information related to any topics.

 

v Intranet: - It is a private network of any organization which is accessed by authorized user related to the organization.

àIn this network all the nodes are connected with IP address to each other.

àThe data transfer speed is very high.

àIt has very high security, so there is less chance to hack.

 

v Extranet: - It is a combination of intranet and internet.

àIn other word, we can say that it is a public intranet network of any organization which is accessed by any user.

àIn this network there is more chance to hack then private network.

 

v HTML: - It stands for hyper text markup language where hypertext means a text that contains a link of any web page and highlighted with any color and markup means styling on text.

àIt is a markup language not a programming language.

àIt is used to develop webpage.

 

v Webpage: - A page that exist on internet is known as webpage.

àIt is accessed by web browser.

àIt contains information related to their website.

 

v Website: - It is a collection of web pages.

àIt is accessed by web browser.

àThe first website is launched by Tim Burners Lee in 1991 whose URL is http://info.cern.ch.

àThe first page of any website is known as ‘Home page’.

 

v Web browser: - It is an application software which is used to access the internet or web page.

àExamples of web browser are such as: Safari, Opera, Netscape, Navigation, chrome etc.

 

v Web address: - It is the unique name of any website by which we access any website.

àExamples: Facebook.com, Youtube.com etc.

 

v Domain name system: - It is text based addressing system.

àIn this system each website has unique name such as: Facebook.com, Youtube.com etc.

à It is the basic combination of domain name and top level domain name. E.g:- Facebook. com

                                Domain name Top level domain name

àTop level domain name of any web address shows types of      websites or root of the domain for their websites or organizations.

 

àWeb server: - It is a centralized computer that stores information about different websites.

àIt accepts the request from the client and response to them through web browser.

àIt has a very high storage capacity as well as high speed processor.

àIt is very big in size then client computer and also stored various software.

àThere are various web servers such as: Apache, IBM lotus, IIS (Internet Information Server) etc.

 

àURL: - It stands for uniform resource locator.

àIt is a address of any webpage.

àWeb browser always uses URL to open web pages.

àIt is a combination of protocol, world wide web and domain name, top level domain name and also path of the file.

àExample: - https://www.facebook.com/index.html.

àThere are two types of URL: -

 

        i.        Absolute URL: - The complete internet address is known as absolute URL.

àIn other word, it is the complete URL of any web page.

àExample: - https://www.facebook.com/index.html.

 

      ii.        Relative URL: - It is the incomplete address.

àIn other word, it is not a complete URL of any web page.

àExample: - https://facebook.com.

 

àISP: - It stands for internet service provider.

àIt provides accessibility to use internet through its server.

àIt usually supplies access rights with user name & passwords.

àExamples of ISPs are BSNL, MTNL and Reliance etc.

 

àModem: - It stands for modulator-demodulator.

àIt is a peripheral device which modulates from sender and demodulates at receiver terminal. Here, modulates means converting of digital signal into analog signal & demodulates means converting of analog signal into digital signal.

àNow a days, all android mobile phones have in built modem that helps to browse internet.

 

àProtocol (IP) address: - It stands for internet protocol address.

àIt is an address of the computer on internet.

àIt identifies the location of the computer that is connected to internet.

àEach device has a unique IP address that is connected to the network.

àIt can be static or dynamic.

àStatic IP address is permanent internet address.

àDynamic IP address is temporary internet address.

àThe IP address is a 32 bit numeric format i.e. 4 numbers separated by quotes & each no. lies between 0to255.

àExample: - 2.168.18.167 etc.

 

NOTE: - To see the IP address of your system then you have to type IPCONFIG command in command prompt.

àHow to see IP address?

        i.       

R

First of all press “windows button +  .    button.

      ii.        Type ‘cmd’ and press ok button.

    iii.        Type ‘IPCOFIG’ in command prompt.

     iv.        And press the ‘Enter’ button.

       v.        Before typing you have to connect your system to internet.

 

àWeb portal: - It is a specially designed website that serves as a single point where various information, resources and services such as: e-mail, forums, search engines etc. are available.

àExamples of such web portals are AOL, MSN, India times, rediff and yahoo.

àWeb portal is also known as ‘Public Portal’.

 

àSwitch: - It is a networking device which is used to create network.

àIt is the smallest hardware device that is used to amplify data signals.

àIt is used to prevent overloading of data in the traffic of a network.

àIt is also responsible for sending data packets between sub-networks.

 

v Hub: - It is also a networking device which is used to create network.

àIt provides common connection between devices in a network.

àIt contains multiple codes in which workstations, servers and peripherals can be connected.

àIt transfer same data to all connected devices because it has no any dedicated connection between devices.

àIt can be either passive or active in nature.

àIt is also known as ‘Repeater’.

 

NOTE: - Amplifying means increasing the strength of signal of data.

 

v Bridge: - It is a networking device which is used to create network.

àIt connects two network together which has same protocol.

àIt improves the data traffic in a LAN as it receives only those data which are destined for them.

 

v Router: - It is an electronic device which has the ability to connect LAN which has different protocol.

àIt forwards the data to the destination on the basis of address.

àIt has the ability to limit the flow of broadcasts.

 

v Gateway: - It is a device that joins two networks of different protocol.

àRouter is also considered as a gateway because it interprets data from one protocol to another protocol of network.

 

v Hyperlink: - A link that exists behind the hypertext.

àIt connects two or more web pages on internet.

àHyperlink is represented by text, image etc which when we clicked by the user then it opens another web page.

àA link to a different section of the same web page is known as ‘Named Anchor’.

 

v Bandwidth: - It refers to the speed of transfer of data over a network.

àIt represents the capacity of network for supporting data transfers.

àIt is represented by bits/second like: 100mbps or 100mb/s.

 

v Protocol: - It refers to the set of rules that regulates the operations.

àIn digital world, it regulates the operation of devices and it communicate between hardware or software and both.

àThe primary protocol of internet is TCP/IP protocol.

àHere, TCP is a connection oriented transmission and IP connect less transmission that represent logical address of the host machine,

àExample: - http://for accessing HTML documents.

 

NOTE: - TCP stands for transmission control protocol and IP stands for internet protocol.

 

Full form of HTTPS is “Hyper text markup language”.

 

v HTTP: - It stands for hyper text transfer protocol.

àIt is used to display information on the internet or world wide web.

àIts main purpose to provide a way to display and retrieve web pages.

àIt is a request/response protocol between client and server.

àHTTP is called a stateless protocol because it doesn’t keep the previously executed command in memory.

 

v FTP: - It stands for file transfer protocol.

àIt is used to transfer or exchanging files between client and server.

àIt is a client server protocol.

àIt may be unauthenticated with user names and passwords.

àThe process of transferring files from client to server is called uploading and the process of fetching data from server to client computer is called downloading.

àTo access FTP server, we must be connected to the internet with an FTP client program.

àFTP client program is a software which is develop to move files back and forth between two computers over the internet.

àExamples of FTP are Filezilla, Dreamweaver etc.

àFTP uses port number 20 to 21.

àFTP is also known as RFC959.

àRFC stands for request for comments.

 

v TCP/IP: - It stands for transmission control protocol/ internet protocol.

àIt is a combination of two protocol TCP and IP.

àTCP ensures reliable transmission of data over the internet & also checks for errors and submit requests for retransmission.

àTCP/IP was developed in 1978 and driven by Bob Kahn and Vint Cerf.

 

v IMAP: - It stands for internet message access protocol.

àIt is standard email protocol that stores email messages on a mail server.

àIt also enables to organize messages into folders, read/unread status etc.

 

v SMTP: - It stands for switch mode power supply.

àIt is a TCP/IP protocol that is used in sending and receiving email.

àIt has limited ability to arrange the messages in the sequence at the receiving end.

àSMTP usually uses internet port number 25 to operate.

 

v Cloud computing: - It is a feature on internet in which we stored our data.

àIt enables the user for sharing of data to another.

àExamples of cloud computing applications are Google drive, Apple i cloud etc.

 

v Advantages of cloud computing: -

        i.            It save our money in state of hard disk or physical storage device.

     ii.            Productivity.

  iii.            Performance.

   iv.            Reliability.