minggu ketiga:data communication

Data communication ? 
-Data Communications is the transfer of data or information between a source and a receiver. The source transmits the data and the receiver receives it. The actual generation of the information is not part of Data Communications nor is the resulting action of the information at the receiver. Data Communication is interested in the transfer of data, the method of transfer and the preservation of the data during the transfer process.
Modem ?
-Modem, device that converts between analog and digital signals. Digital signals, which are used by computers, are made up of separate units, usually represented by a series of 1's and 0's. Analog signals vary continuously; an example of an analog signal is a sound wave.

Modems are often used to enable computers to communicate with each other across telephone lines. A modem converts the digital signals of the sending computer to analog signals that can be transmitted through telephone lines. When the signal reaches its destination, another modem reconstructs the original digital signal, which is processed by the receiving computer.

To convert a digital signal to an analog one, the modem generates a carrier wave and modulates it according to the digital signal. The process of receiving the analog signal and converting it back to a digital signal is called demodulation. The word "modem" is a contraction of its two basic functions: modulation and demodulation.

Amplitude , Period and Frequency 

-Amplitude (A): how high the peaks are or how low the troughs are, in meters.

The displacement is how far the wave vibrates / oscillates about its equilibrium (center) position.

Amplitude is correlated with the total energy of the system in periodic motion. Larger amplitude = greater energy.

Period (T): the time it takes for one cycle, in seconds.

Frequency (f): the rate, or how many cycles per second, in Hertz (cycles per second)

Coaxial Cable

-It consists of 2 conductors. The inner conductor is held inside an insulator with the other conductor woven around it providing a shield. An insulating protective coating called a jacket covers the outer conductor.

The outer shield protects the inner conductor from outside electrical signals. The distance between the outer conductor (shield) and inner conductor plus the type of material used for insulating the inner conductor determine the cable properties or impedance. Typical impedances for coaxial cables are 75 ohms for Cable TV, 50 ohms for Ethernet Thinnet and Thicknet. The excellent control of the impedance characteristics of the cable allow higher data rates to be transferred than Twisted Pair cable.

Optical Fibre

- consists of thin glass fibres that can carry information at frequencies in the visible light spectrum and beyond. The typical optical fibre consists of a very narrow strand of glass called the Core. Around the Core is a concentric layer of glass called the Cladding. A typical Core diameter is 62.5 microns (1 micron = 10-6 meters). Typically Cladding has a diameter of 125 microns. Coating the cladding is a protective coating consisting of plastic, it is called the Jacket.

Data Transmission

-The physical connection determines how many bits (1's or 0's) can be transmitted at a single instance of time. If only 1 bit of information can be transmitted over the data transmission medium at a time then it is considered a Serial Communication.

If more than 1 bit of information is transmitted over the data transmission medium at a time then it is considered a Parallel Communication. 

Data Flow

Data flow is the flow of data between 2 points. The direction of the data flow can be described as:

Simplex: data flows in only one direction on the data communication line (medium). Examples are Radio and Television broadcasts. They go from the TV station to your home television.

Half-Duplex: data flows in both directions but only one direction at a time on the data communication line. Ex. Conversation on walkie-talkies is a half-duplex data flow. Each person takes turns talking. If both talk at once - nothing occurs!

Full-Duplex: data flows in both directions simultaneously. Modems are configured to flow data in both directions. 

Minggu kedua:Web Searching

example of web browser

A web browser can be defined as an application software or programme designed to enable users to access,retrieve and view documents and other resources on the internet .the example of web browser is like google chrome,mozilla firefox and safari.

Search engine

search engine is designed to search for information on the World Wide Web .The information may consist of web pages,images,information and other types of files

search engine

Skill to know

There are some skill that we had to know in term of improving ourselves as a internet user .when we open files,it will be on certain format such as pdf,html,jpg,gif,txt and so on .We must know the uses of certain button in the web such as refresh,back and forward . The knowledge of bookmarking,clear cache,clear history,clear URL and setting default page must be know by the user too,to make sure that we can maximise the usage of the internet .

Minggu pertama:telekomunikasi dan rangkaian

model shannnon weaver

oke .telekomunikasi ? di mana asal perkataan ini ?  kita selalu sebutnya di dalam kehidupan seharian,tapi tahukah anda di mana asalnya perkataan ini ? telekomunikasi berasal dari perkataan Perancis " télécommunication" .Ianya ialah hasil gabungan dari perkataan greek iaitu tele yang bermaksud jauh dan juga perkataan latin communicare iaitu berkongsi .Perkataan Perancis Telecommunication pertama kali digunakan pada 1904 oleh seorang jurutera yang juga seorang novelis Perancis yang bernama Eduard Estaunie .Manakala untuk rangkaian pula,ianya bermaksud penyambungan antara dua buah komputer atau lebih .Jadi dapat dirumuskan,dalam telekomunikasi dan rangkaian ni ianya bertujuan untuk macam mana kita nak berhubungan dengan orang lain dan mendalami dengan lebih mengenai telekomunikasi ini . oke ini antara model komunikasi yang dapat saya berikan .. 






Terdapat 6 elemen utama di dalam komputer dan teknologi komunikasi ni .
1)People
2)Procedure
3)Data / Information
4)Hardware
5)Software
6)Communication / connectivity


-keenam-enam elemen ni sangat lah penting dan ketiadaan salah satu darinya akan besar mempengaruhi kepada struktur komputer dan teknologi komunikasi ini .

kene aktif balik la blog saya nmpknye :)

fuhhh fuhhhh .berhabuk bai .bape tahun da tak bukak ni .tah la . haha .nway,dalam sem 2 ni,ade satu subjek ,iaitu telecommunication and networking dan salah satu dari assignment yang diberi kepada kami ialah,wujudkan blog atau develop blog kami ini supaya ianya mempunyai unsur2 T&N ni dan mempunyai summary ringkas dari ape yg kami dpat week by week. .jadi,baiklah ,saya akn cuba sedaya upaya merajinkan diri ini untuk mengupdate blog sy ni .hehe .oke,jumpe ag nanti .kbai !

harder faster better stronger

rajin plak nak post 2 entry skali ni .dlu kemaen malas .haha ,da alang2 kan .oke ,kali ni aku nak cite pasal weight management . firstly ,syukur alhamdulilah , lepas setahun lbey aku usaha , usaha tu , tak makan nasi sebulan , pumping setiap hari ,sit up ,squat jump ,skipping ,jogging , cycling n macam2 lagi la yang aku da cube . . akhirnye ,dpat gak feed back camni 'eh ko da kurus , da kurus la ko bro , bro ko maen gym ke ? ,asal laen muke ko skrang ? ' lbey kurang camtu la .pastu aku test la baju kan ,eh btol la , size M , S pon da lepas . haha .alhamdulilah . byk sebab nye aku nak kurus ni ,antaranye ,sebab cinta aku yg amat teramat kat dye ni . dye ni ? ragbiiii .hehe .aku tak nak awek pon takpe , asal aku ade ragbi  .haha .statement ni wat masa ni je eh .ahaha .oke , aku nak fitkan badan aku ni ,so aku bole jadi utility player , n chance utk maen ke peringkat tertinggi tu makin tinggi la kot kan ? sebab impian saya sgt la tggi ,even orang ckap ragbi ni takde future ,tapi takpe , i have my own plan ,dgn parent pon da paham n da sokong kan .thanx mama n papa .  :) . saya akan terus mengfitkan badan saya ni , bagi nampak berketul sikit .hehe .doakan saya guys ,thanx a lot . so ,jumpe ag .insyAllah . daa

100 day as a tescorian . :)

dup dap dup dap , naek moto , naek kete ,gosok baju ,online ,makan ,tido ,exercise , cuti ,keje ,maen ragbi . last last ,aku tgk tarikh balik . pergh .lame jugak aku jadi tescorian ni kan ?dari time aku masuk tu ,da bape orang da bertukar dalam department aku ,belom department laen lagi .so,,makin bertmbah la kawan baru .haha .em ,,baru aku pasan .dlu kemaen aku menghitung hari nak abes kontrak tu .last last ,lepas dipujuk oleh Trading Manager aku (hehe poyo skit) . aku sambung la lagi sebulan setengah . camtu la cite nye .keje kat situ , mmg best ,kawan2 sekerja ,kerja dye,gadis2 .hehe .bole kate ,yg tak best nye kat tesco ni ,ialah gajinye . kureng skit .hehe .nak gaji lbeyyyyy .takpe la ,aku pon menghitung hari je ag ni .so ,just nak enjoy hari2 terakhir aku sebagai tescorian .so ,enjoy life guys . :)

new life,new passion

aku da bekerja,, ye bekerja,sementara menunggu result yang akan kua lagi berapa detik ni .bekerja di tesco rawang .mule2 ingat tak nak jadi full time,,sebab bagi aku macam takde life .tapi alang2 da dapat tu,,aku teruskan je la. n hari ni,,14 februari,, genap sebulan aku jadi tescorian .(bak kate pijat) haha .keje die agak penat .n aku suke gak la,,sebab berat badan aku pon turun sekali .haha .bajet dalam 2 bulan ag aku stop .nak cari nafkah kan?? haha .ok,,till then. daa .