KEY POINTS NETWORKING COMPUTER SCIENCE 12TH CBSE

1.       Inconnection of electronics device (computer ) by communication media is known as netwok.
2.       Interconncection of million of network in public way is internet
3.       Private network over internet is known as       Intranet
4.       Network advantage is sharing and communication .
5.       Few kilometer netwok is lan
6.       Network in city is MAN
7.       Network in large geographics area is WAN like continent or country network.
8.       Internet is example of WAN.
9.       1G,2G,3G ,4G is generation of Mobile Communicaiton.
10.    2G is GSM with GPRS+EDGE
11.    3G it’s a UMTS technology HDSA
12.    Amplifier amplify or boost weak signal
13.    Repeater regenerate or repeat original signal.
14.    Bridge reduce traffic by divide network .
15.    Switch is multiport bridge .
16.    Switch ,hub are multiport connecting device
17.    Hub is multiport repeater .
18.    Hub,amplifier ,repeater is not intelligent network device
19.    Device that assist to form network is network device
20.    Network device is Router,switch,bridge Hub,Repeater
21.    Switch communicate using  hardware address of device .
22.    Router communicate using IP address of device
23.    Router used for inter network communication .
24.    Each device in network has mac address and ip address
25.    Router decide shortest route from source to destination .
26.    Modem means modulation and demodulation .
27.    Hub always broadcast without filtering it.
28.    switch send data directly from source to destination using hardware address.
29.    Connection between network device perform by communication media
30.    Media can be of two type
1.wired 2.wireless       31. wired media example is :twisted pair,coaxial cable,optical fibre.       32.twisted pair is cheapest and easy maintenance cable .      33. optical fiber based in total internal reflection concept .      34 .optical fiber is communicate in form of light(LASER).     35.in optical fiber glass like medium used.     36. optical fiber has highest bandwidth over other media .   37. wireless communication media is micro wave,radio wave ,infrared  etc.38 microwave is fastest and reliable wireless communication media39.inter lan communication way.  1.dial up 2.leased line 3.broadband  4.optical fiber40 broadband is cheapest for  inter lan communication.41.leased line provide private and fast network.42.optical fiber is fastest communication for both lan and interlan communication.43.for long distance more than 90 m repeater is used than.44.network connecting and arrangement way can be different .this is topology of network.45. topology is different way of connecting the network.46.topology is :ring topology,bus ,star,mesh ,hybrid.47 star is most common topology.48 hybrid topology is combination of more than one topology.49.switching is technique to form path between source and destination50 switching technique is message,packet ,circuit.51.voice communication perform over circuit switching.52.data communication perform over packet switchingà both messege and packet switching technique is store and forward technique .
àmessge switching require more buffer than packet switching .
53. smallest unit of data that can be transfer is known as packet.54 whole data is divided into so many small packets.55.in circuit switching whole channel is allotted for two party.56. in packet switching channel may be shared by too many parties.57.packets not essentially follow same path always.58.voice communication perform  always in one  path.59 open source software is software thos source code available with software.like unix ,linux ,android60 software which Is available free of cost is free software or freeware .61 software which is free of cost and those source code is also available with software is known as free and open softwareor FLOSS . 62 freeware is software which is free of cost available like :opera,Mozilla ,safari,63 shareware are software which is available for limited period and then its need to pay for it.Like  quickheal,macfee ,anivirus64 floss are free and open source software.65 80-witch 20 rules says that traffic of network within network is 80 % and  traffic outside to network  is 20%.66stp:spanning tree protocol-used by network to eliminate any cicular path .67 wireless in local loop is limited area wireless communication technology.used in hilly area.68.microwave communication is best for hilly area.69 firewall is software or hardware which protect your network or system from malicious or unauthorised  attack .70 cyber crime :illegal criminal activity happen in cyber space.71cyber law:legal rules form to protect from cyber crime .72 it act 2000:cyber law form for regulation of e-commerce transaction in india .73node:device  which connected to network is known as node.74 ipr:intellectual property is  like idea ,logo,software ,sign of firm or personel.keeping it safe and not to be used without owner permissionis intellectual property right.75 proprietary software:software which has owner and its can be sell,distribute ,copy ,move without its permission.76.spam :junk  mail sent for purpose of marketing ,selling etc.77worm :malicious program ,that replicate itself on system or network.78Trojan horse: A malicious program which can enter though spam mail .Which hide itself in back ground and send sensitive information to intruder.79.virus :malicious program that did damaging activity like os crashing ,boot sector crash,file system crash.80 virus are of  3 type -1.file infector2.boot sector virus 3. Macrovirus81 cookies :text data send from web server to web browser .so it keep record of user activity and status.82.web server :a system/softwarefulfill web browser request.83: web  browser :a software whichaccess web service84.Authorization: mechanism that determine where u r  right to enter into system.85authentication: mechanism to determine that ur connected with right person.86 client side scripts: vb script ,java script,php87 server side script: PHP,perl,ASP,JSP88web hosting :providing space and connectivity for web server .89web hosting  type :free,virtual,dedicatd ,co-location etc90domain :internet address in character format is domain.91

Com	Commercial
Edu	education
Gov	goverment
Mil	Military
Net	Network resources
Org	organization
Co	comany
Tv	television
In	india
Au	australia
Uk	United kingdom

92 url:uniform location of web contained
93url format:type://address/pathEx http ://jnvtikamgarh.com/staff.html94telnet: a network program to access remote syste.95RJ-45:registered jack 45,LAN connector96EVDO:evalution data optimized97: Enhanced Data Rates for GSM Evolution
98: Cloud computing, also known as 'on-demand computing', is a kind of Internet-based computing, where shared resources, data and information are provided to computers and other devices on-demand
99;web page:doc’s conatained hyper text or multimedia100:www:worlds extended  contained of web pages.