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ARPANET, a US research network, carried its first message on 29 October 1969, from the University of California, Los Angeles, to the Stanford Research Institute. It split data into small “packets” that travelled separately and were reassembled on arrival, and it became the main forerunner of the internet.

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ARPANET was funded by ARPA, a research agency of the US Department of Defense, so that scientists could share scarce, expensive computers at a distance. Its packet switching drew on ideas by Paul Baran in the United States and Donald Davies in Britain. On that first evening the UCLA student Charley Kline typed “login”, but the Stanford computer crashed after two letters, so the first message was simply “lo”; about an hour later the login worked. The network was declared operational in 1971 and soon carried an early form of email. In 1974 Vint Cerf and Bob Kahn described a way for separate networks to pass data between them, which grew into TCP/IP, the common rules the internet still uses. ARPANET switched to TCP/IP on 1 January 1983, a date often called the birth of the internet, and was shut down in 1990.

Türkçe oku
ABD'nin bir araştırma ağı olan ARPANET, ilk mesajını 29 Ekim 1969'da Los Angeles'taki Kaliforniya Üniversitesi'nden (UCLA) Stanford Araştırma Enstitüsü'ne iletti. Veriyi küçük “paketlere” bölüyordu: Paketler ayrı ayrı yol alıyor, varınca yeniden birleşiyordu. ARPANET, internetin başlıca öncüsü oldu.

ARPANET'i, ABD Savunma Bakanlığı'na bağlı araştırma ajansı ARPA finanse etti. Amaç, bilim insanlarının az bulunan pahalı bilgisayarları uzaktan ortaklaşa kullanabilmesiydi. Veriyi paketlere bölerek gönderme fikri, ABD'de Paul Baran'ın ve İngiltere'de Donald Davies'in çalışmalarına dayanıyordu. O ilk akşam UCLA öğrencisi Charley Kline “login” yazmaya başladı, ama Stanford'daki bilgisayar iki harften sonra çöktü; yani ilk mesaj yalnızca “lo” oldu. Yaklaşık bir saat sonra ikinci denemede oturum açıldı. Ağ 1971'de resmen hizmete girdi ve kısa sürede e-postanın ilk biçimlerinden birini taşımaya başladı. 1974'te Vint Cerf ile Bob Kahn, ayrı ağların birbirine veri aktarabilmesi için bir yöntem tanımladı; bu yöntem, internetin bugün de kullandığı ortak kurallar olan TCP/IP'ye dönüştü. ARPANET 1 Ocak 1983'te TCP/IP'ye geçti; bu tarih çoğu zaman internetin doğum günü diye anılır. ARPANET'in kendisi ise 1990'da kapatıldı.

Sources and further reading

Background reading: History of the Internet
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