SEJARAH JARINGAN KOMPUTER

Konsep jaringan komputer lahir tahun 1940-an di Amerika dari sebuah proyek pengembangan komputer MODEL I di laboratorium Bell dan group riset Harvard University, dipimpin Profesor H. Aiken. Pada mulanya proyek tersebut hanyalah ingin memanfaatkan sebuah perangkat komputer yang harus dipakai bersama. Untuk mengerjakan beberapa proses tanpa banyak membuang waktu kosong dibuatlah proses beruntun (Batch Processing), sehingga beberapa program bisa dijalankan dalam sebuah komputer dengan kaidah antrian.

Ditahun 1950-an ketika jenis komputer mulai membesar sampai terciptanya super komputer, maka sebuah komputer mesti melayani beberapa terminal. Untuk itu ditemukan konsep distribusi proses berdasarkan waktu yang dikenal dengan nama TSS (Time Sharing System), maka untuk pertama kali bentuk jaringan (network) komputer diaplikasikan. Pada sistem TSS beberapa terminal terhubung secara seri ke sebuah host komputer. Dalam proses TSS mulai nampak perpaduan teknologi komputer dan teknologi telekomunikasi yang pada awalnya berkembang sendiri-sendiri.

Memasuki tahun 1970-an, setelah beban pekerjaan bertambah banyak dan harga perangkat komputer besar mulai terasa sangat mahal, maka mulailah digunakan konsep proses distribusi (Distributed Processing). Dalam proses ini beberapa host komputer mengerjakan sebuah pekerjaan besar secara paralel untuk melayani beberapa terminal yang tersambung secara seri disetiap host komputer. Diperlukan perpaduan antara teknologi komputer dan telekomunikasi, karena selain proses yang harus didistribusikan, semua host komputer wajib melayani terminal-terminalnya dalam satu perintah dari komputer pusat.

Setelah harga komputer mikro sudah terjangkau dan konsep proses distribusi sudah matang, maka penggunaan komputer dan jaringannya sudah mulai beragam dari mulai menangani proses bersama atau komunikasi antar komputer (Peer to Peer System) tanpa melalui komputer pusat. Kemudian berkembang teknologi jaringan lokal yang dikenal dengan sebutan LAN. Demikian juga ketika Internet berkembang, maka sebagian besar LAN yang berdiri sendiri mulai terhubung & terbentuk jaringan raksasa WAN.



PENGERTIAN JARINGAN KOMPUTER

Jaringan komputer adalah kumpulan komputer, printer dan peralatan lainnya yang terhubung dalam satu kesatuan. Setiap komputer printer atau peripheral yang terhubung dengan jaringan disebut node.

Secara umum jaringan komputer dibagi atas lima jenis, yaitu :

1. Local Area Network (LAN)

merupakan jaringan milik pribadi di dalam sebuah gedung atau kampus yang berukuran sampai beberapa kilometer.

2. Metropolitan Area Network (MAN)

pada dasarnya merupakan versi LAN yang berukuran lebih besar dan biasanya menggunakan teknologi yang sama dengan LAN. MAN dapat mencakup kantor-kantor perusahaan yang letaknya berdekatan atau juga sebuah kota.

3. Wide Area Network (WAN)

jangkauannya mecakup daerah geografis yang luas, seringkali mencakup sebuah negara bahkan benua. WAN terdiri dari kumpulan mesin-mesin yang bertujuan untuk menjalankan program-program (aplikasi) pemakai.

4. Internet

pada dasarnya internet merupakan kumpulan jaringan yang terinterkoneksi. Hal ini terjadi karena orang yang terhubung ke jaringan sering berharap untuk bisa berkomunikasi dengan orang lain yang terhubung jaringan lainnya. Untuk melakukan hal ini diperlukan sebuah mesin yang disebut gateway guna melakukan hubungan dan melaksanakan terjemahan yang diperlukan, baik perangkat keras maupun perangkat lunaknya.

5. Jaringan Tanpa Kabel

merupakan solusi terhadap komunikasi yang tidak bisa dilakukan dengan jaringan yang menggunakan kabel.



PENGERTIAN KOMUNIKASI DATA

Komunikasi data adalah bagian dari telekomunikasi yang secara khusus berkenaan dengan transmisi atau pemindahan data dan informasi diantara komputer-komputer dan piranti-piranti yang lain dalam bentuk digital yang dikirimkan melalui media komunikasi data. Data berarti informasi yang disajikan oleh isyarat digital.

Komponen Komunikasi Data, antara lain:

1. Penghantar atau pengirim, adalah piranti yang mengirimkan data

2. Penerima, adalah piranti yang menerima data

3. Data, adalah informasi yang akan dipindahkan

4. Media pengiriman, adalah media atau saluran yang digunakan untuk mengirimkan data

5. Protokol, adalah aturan-aturan yang berfungsi untuk menyelaraskan hubungan



MANFAAT JARINGAN

Jaringan memungkinkan manajemen sumber daya lebih efisien, misalnya :

• Pengguna dapat saling berbagi printer tunggal dengan kualitas tinggi, dibandingkan memakai printer kualitas rendah di meja kerja masing-2.

• Lisensi perangkat lunak jaringan dapat lebih murah dibandingkan lisensi stand-alone terpisah untuk jumlah pengguna sama.

Jaringan membantu mempertahankan informasi agar tetap andal dan up-to-date.

• Sistem penyimpanan data terpusat yang dikelola dengan baik memungkinkan banyak pengguna mengakses data dari berbagai lokasi yang berbeda, dan membatasi akses ke data, saat sedang diproses.

Jaringan memungkinkan kelompok-kerja berkomunikasi dengan lebih efisien.

• Surat dan penyampaian pesan elektronik merupakan substansi sebagian besar sistem jaringan, disamping sistem penjadwalan, pemantauan proyek, konferensi online dan groupware, dimana semuanya membantu team bekerja lebih produktif.

Jaringan membantu usaha dalam melayani klien mereka secara lebih efektif.

• Akses jarak jauh ke data terpusat memungkinkan karyawan dapat melayani klien di lapangan dan klien dapat langsung berkomunikasi dengan pemasok.

Sumber

• http://mufari.wordpress.com/2008/06/24/sejarah-jaringan-komputer/

• http://www.geocities.com/fadelku/network/jaringan.html

What Is the Meaning Web?

The World Wide Web is a global, seamless environment in which all information (text, images, audio, computation services) that is accessible from the internet can be accessed in a consistent and simple way by using a standard set of naming and access conventions. Whew! Quite a statement, but it is true, and it exists today. You are on the web now considering.

You can access sites all over the world. You can connect from your desktop to thousands of Web servers simply by “clicking” on a selection (the underlined words), or by entering a specific address. You can connect to many different types of systems and not be aware of the differences.

You can access many different types of information text, images (like the heading on this page, and the diagrams we’ll use), audio, computation services again, usually with no extra work on your part.

You are using a single Web browser to do this. One tool accessing many different types of systems, information across the world. Already we can see some of the unique aspects of the Web that make it so popular.

GREEN - GREEN GRASS OF HOME

GREEN - GREEN GRASS OF HOME

The old hometown looks the same

As I step down from the train

And there to meet me is my Mama and Papa

Down the road I look and there runs children

Hair of gold and lips like cherries

It’s good to touch the green, green grass of home

Yes, they’ll all come to meet me

Arms reaching smiling sweetly

It’s good to touch the green, green grass of home

The old house still standing

The paint is cracked and dry

And there is that old oak tree that I used to play on

Hair of gold and lips like cherries

It’s good to touch the green, green grass of home

Then I awake and look around me

At four grey walls that surround me

And I realized that I was only dreaming

For there’s a guard and there’s a sad old padre

Arm in arm we’ll walk at daybreak

Again I’ll touch the green, green grass of home

Yes, they’ll all come to meet me

In the shade of that old oak tree

As they lay me beneath the green, green grass of home

The Cause Of Lightning

Lightning has been a mystery since early times. People of ancient civilizations believe angry gods threw lightning bolts from the sky. Nobody understood that lightning resulted from electricity until Ben Franklin flew a kite with a key dangling from the string, and it was struck by lightning.

In current times, it is known that lighting has a very scientific cause Generally, within a storm cloud, friction from water and ice-laden clouds creates a negative charge at the bottom of the cloud. When that charge grows too great for the air to hold it back, it is united with a positive charge from the Earth, creating a channel of electricity that flows between the two points. The charge remains invisible as it moves towards the ground until it meets the charge rising from the ground. Once they meet, a fifty thousand degree current superheats the air around the channel, resulting in an explosion of sound known as thunder. In fact, very recently it has been discovered that occasionally the positive charges appear at the bottom of the cloud, which are them met by negative charges from earth.

Generally, people are injured by lightning when they are in the open, near or in water, or near tall structures like trees. Golfers, swimmers, beach-goers, and outdoor workers are in greatest danger. The greatest number of victims are males, but it is believed that this is because males are more likely to be in the places where lightning strikes. When lightening is about to strike, one feels an odd, tingling sensation, and one’s hair stands on end. Of course, there is little change to do anything about it, because the full blow will occur within a second and be over in a couple of seconds. The victim may be thrown, lose consciousness, be burned, die, or suffer permanent injury. Some people recover completely, but others do not.

Motion Sickness

Motion sickness comes in many forms, not just seasickness. Ninety percent of the human race is susceptible to motion sickness of one kind or another. Some people become sick when they sit in back seat of a car, other cannot read or look at a map in any kind of moving vehicle. People get motion sickness on air planes, motorcycle, amusement park rides, and even on camels. Scientists have learned that motion sickness occurs when the brain is trying to make sense of a situation and there are too many conflicting messages. While the eyes are sending one message, the ears are trying to send a message about balance. The skin and bone joints, sensitive to air pressure, send another message.

Many people who got sick have experienced violent motion sickness try to avoid travel. But that is not always possible. So travelers should employ some well known strategies to avoid getting sick. The most useful strategy concerns food: eat a light meal before travelling and bring along a packet of plain soda crackers to snack on regularly. Avoid alcoholic and carbonated beverages, high-fat foods, and spices. Care in choosing the location of your seat is another important strategy. In a car, sit at the front and keep your eyes fixed on the horizon.

People who still got sick after trying these strategies can try medical help. Some rely on over-the counter medications, although some of them can make you sleepy. Others use simple ginger capsules to settle their stomach. A large number of travelers use pressure bands on theirs wrists. It is not clear how these bands work, but they do prevent motion sickness.

INDONESIAN NEWSPAPERS

Nowadays, there are a great number of newspapers published in Indonesia, almost in each province, one or more are circulated every day.

There are two kinds of newspaper. They are national and regional ones. The national ones report what happened in whole provinces and the regional ones report what happened in the certain provinces but both of them sometimes describe what happened in our country and the situations in the other country.

The arrangement of the newspapers generally consists of headlines, articles, classified ads and sports. The headlines usually inform the government programmer or the people’s life, the articles contain the people’s life, religion, law, crime and the others, classified ads often inform the people’s business and the sports inform a lot of kinds of sports which the people play and the names of sport men or sport women and their achievements. And the writing of the newspapers are not the same as the books. In one page is not full for one topic but more than one topics and it consists of columns. One topic can consist of one or more columns and if it is too long, it must be continued to another page.

Whatever forms and kinds of newspaper, the press must prepare the news as interesting as possible for the readers and don’t forget to do our president’s message that “Indonesia press must inform the development of information which is not contrary to Pancasila and UUD 1945”.

Although there are a lot of kinds of newspaper, all of them are important for us to read to get a lot of information and increase our knowledge.