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WonderNetwork history fact

Almost everything sent over the internet travels by packet switching: data is cut into small packets, each carrying its address, which can take different routes across the network and are put back together at the destination.

Internet Society / National Physical Laboratory

TechnologyHistory

The story behind the card

Older telephone networks reserved a whole line from one end to the other for the length of a call, even during silences. With packet switching, many users share the same links, and if one route fails, packets go another way. The idea came independently from two people in the 1960s. At the RAND Corporation in the United States, Paul Baran designed it in the early 1960s for a network that could survive damage in a war. From 1965, Donald Davies at Britain's National Physical Laboratory reached a similar design to let many computer users share lines efficiently, and coined the term packet switching. His laboratory's network ran from 1970, and his ideas helped shape ARPANET, the forerunner of the internet.

Türkçe oku
İnternette gönderilen neredeyse her şey paket anahtarlamayla yol alır: Veri, her biri adres bilgisi taşıyan küçük paketlere bölünür; paketler ağda farklı yollardan gidebilir ve varış noktasında yeniden birleştirilir.

Eski telefon ağları, bir görüşme boyunca iki uç arasındaki hattın tamamını, sessiz anlarda bile, o görüşmeye ayırırdı. Paket anahtarlamada ise pek çok kullanıcı aynı bağlantıları paylaşır; bir yol kesilirse paketler başka yoldan gider. Fikir 1960'larda iki kişinin aklına birbirinden habersiz geldi. ABD'deki RAND Corporation'da Paul Baran, 1960'ların başında savaşta hasar görse bile çalışmayı sürdürebilecek bir ağ tasarladı. İngiltere'deki Ulusal Fizik Laboratuvarı'nda (NPL) Donald Davies ise 1965'ten itibaren, hatları çok sayıda bilgisayar kullanıcısının verimli biçimde paylaşabilmesi için benzer bir tasarıma ulaştı ve “paket anahtarlama” terimini o buldu. Laboratuvarın ağı 1970'te hizmete girdi; Davies'in fikirleri internetin öncüsü ARPANET'in biçimlenmesine de katkıda bulundu.

Sources and further reading

Background reading: Packet switching
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