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  • The Internet in the year Two Thousand and 9

  • We send emails,

  • make calls over the internet, and discuss topics we take an interest in

  • even our banking is going virtual!

  • But what we take for granted today

  • was only vague idea fifty years ago.

  • In order to understand how we got this far,

  • let's go back to

  • nineteen fifty-seven

  • when everything began.

  • Before nineteen fifty-seven, computers only worked on one task at a time;

  • this is called a batch processing.

  • Of course this was quite ineffective.

  • With computers getting bigger and bigger, they had to be stored in special cooled

  • rooms;

  • but then the developers couldn't work directly on the computers anymore,

  • specialists had to be called in to connect them.

  • Programming at that time meant a lot of manual work and the indirect connection

  • to the computers lead to a lot of bugs, wasting time, and fraying the developers nerves.

  • The year nineteen fifty seven marks a big change.

  • A remote connection had to be installed

  • so that the developers could work directly on the computers;

  • at the same time the idea of time sharing came out.

  • This is the first concept in computer technology -

  • to share the processing power of one computer with multiple users.

  • On October fourth nineteen fifty-seven, during the cold war,

  • the first unmanned satellite, Sputnik One

  • was sent into orbit by the Soviet Union.

  • The fear of a missile gap emerged.

  • In order to secure America's leading technology, the US founded the Defense

  • Advanced Research Project Agency in February nineteen fifty-eight.

  • At that time

  • knowledge with only transferred by people.

  • The DARPA planned a large-scale computer network in order to accelerate

  • knowledge transfer

  • and avoid the doubling up above already existing research.

  • This network would become the ARPANET

  • Furthermore three other concepts were to be developed which are fundamental for

  • the history of the internet.

  • The concept of a military network by the Rand Corporation in America.

  • the commercial network of the National Physical Laboratory in England

  • and the scientific network Cyclades in France

  • the scientific

  • military

  • and commercial approaches of these concepts are the foundations for our modern

  • internet

  • let's begin with the ARPANET the most familiar of these networks

  • it's development began in nineteen sixty six

  • universities which are really quite cautious about sharing their computers

  • therefore small computers were put in front of the mainframe

  • this computer the Interface Message Processor took over control of the

  • network activities while the mainframe was only in charge of the initialization

  • of programs and data files.

  • At the same time the IMP also served as the interface for the mainframe.

  • Since only the IMPs were interconnected in a network this was also called an IMP

  • subnet.

  • For the first connections between the computers

  • the network working group developed the Network Control Protocol,

  • later on the NCP was replaced by the more efficient Transmission Control

  • Protocol.

  • The specific feature of the TCP is the verification of the final transfer.

  • Let's take a short detour to England.

  • Since the NPL network was designed on a commercial basis,

  • a lot of users

  • and file transfers were expected,

  • in order to avoid congestion of the lines, the sent files were divided into

  • smaller packets

  • which were together again at the receiver;

  • packet switching was born.

  • In nineteen sixty two

  • American aircraft discovered middle and long-range missiles in Cuba which were

  • able to reach the United States.

  • This stoked fear of atomic conflict.

  • At that time information systems had a centralized network architecture.

  • To avoid a breakdown during an attack

  • a decentralized network architecture had to be developed

  • which in case of loss of a node

  • would still be operative.

  • Communication still used to work through radio waves,

  • that would have caused problems in case of an atomic attack.

  • The ionosphere would be affected and the long way a radio waves wouldn't work

  • anymore;

  • therefore they had to use direct ways which however don't have a long range.

  • A better solution was the model of a distributed network,

  • thus long distances could be covered with a minimum of interference.

  • Another milestone followed with the development of the French network

  • Cyclades.

  • Since Cyclades had a far smaller budget than ARPANET and thus also fewer

  • nodes,

  • the focus was laid on the communication with other networks.

  • In this way the term Internet was born.

  • Moreover

  • Cyclades' concept went further than ARPA's and the NPL's.

  • During communication between sender and receiver the computers were not to

  • intervene anymore, but simply serve as a transfer node.

  • Cyclades' protocols went through all machines using a physical layer that was

  • implemented into the hardware

  • providing a direct connection with the receiver

  • and an end to end structure.

  • Inspired by the Cyclades network and driven by the incompatibility between

  • the networks, that connection gained in importance everywhere.

  • The phone companies develop the X point 2 five protocol which enabled

  • communication through their servers in exchange for a monthly basic charge

  • of course.

  • DARPA's transmission control protocol was to connect the computers through gateways,

  • and the international organization for standardization designed the OSI

  • reference model

  • the innovation of OSI

  • was the attempt to standardize the network from it ends and the channels

  • division into separate layers.

  • Finally the TCP assimilated the preferences of the OSI reference

  • model and gave way to the TCP/IP protocol

  • a standard which guaranteed compatibility between networks,

  • and finally merged them, creating the Internet.

  • by February twenty eighth nineteen ninety the ARPAnet hardware was removed

  • but the Internet was up and running!

The Internet in the year Two Thousand and 9

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互聯網的歷史 (History of the Internet)

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    hsun520 發佈於 2021 年 01 月 14 日
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