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互联网历史之一 | 互联网是如何诞生的 – 译学馆
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互联网历史之一 | 互联网是如何诞生的

How the Internet Was Invented | The History of the Internet, Part 1

当你点击了这个视频
When you clicked on this video,
你的计算机就给YouTube的计算机发送了一条信息
your computer sent a message to a computer at YouTube
它可能与你相隔几个州 几个国家 或几大洲那么远
that might be states or countries or continents away.
它不知道这信息是怎么接收到的
It didn’t know how to get the message there,
但它还是发出去了
but it sent it anyway.
这条信息大概半秒钟就到达了
The message probably took about half a second to arrive and
并告诉YouTube的计算机去寻找一份文件
told YouTube’s computers to search for a file
— 文件都是一组与其周围的数十亿几乎难以分辨出来的1和0组成的
— a set of ones and zeros practically indistinguishable from the billions all around it
然后把那份文件发回给你
— and to send that file back to you.
YouTube的计算机再把文件一条一条地发到你的计算机
YouTube’s computers then sent the file back to your computer piece by piece,
这些1和0就被转译成这个视频的开始了
where those ones and zeros were interpreted as the start of a video.
甚至当你看着我说话的时候 这些1和0仍在不停地输进
And the ones and zeros are still streaming in, even while you’re watching me talk.
想一想 它太神奇了
It’s pretty amazing when you think about it.
如果你好奇我们是怎么到了这样一个由几十亿计算机
And if you’re curious how we ended up in a world where billions of computers are all
通过一个叫互联网的奇怪架构相互连接起来的世界
interconnected through this strange structure that we call the Internet,
那么你就来对地方了
then you’re in the right place.
因为这就是给你讲有关互联网历史的迷你系列视频
Because this is the start of a mini-series of videos about the history of the Internet,
从几台计算机一起工作的初次尝试
from some of the first attempts at making computers work together
一直到现代社交网络 便携视频会议
all the way through modern social networks and on-the-go video conferences.
开发合适的软件 硬件 科技和
Developing the right combination of software, hardware, technology,
营销的组合 用了几十年的时间
and marketing took decades,
所以我们不可能讲到所有重要的工程和发明
so we won’t be able to talk about every important engineer and invention.
但我们希望你能加入我们 和我们一起探讨一些至关重要的
But we hope you’ll join us as we investigate some of the crucial ideas
想法和事件
and events along the way.
人们很早就开始让多台计算机一起工作
People started making computers work together pretty early on
早到从二战时期开始
as far back as World War II,
那时候 计算机还是体积很大 很笨重的机器
when computers were big, clunky machines
除了解决很难的数学题外 其他做不了什么
that didn’t do much more than solve really difficult math problems.
即使是当时最好的计算机
Even with the best computers of the day,
要解决一个与制作原子弹相关的一个复杂的物理问题
it could take months to solve just one of the complicated physics problems
也需花上几个月的时间
involved in making the atomic bomb.
但是 由物理学家Richard Feynman 领带的一个研究团队找到了一个一次性解决许多问题的方法
But a team led by physicist Richard Feynman found a way of solving a bunch of problems
他们让没在解决某部分问题的计算机
at once: when computers weren’t being used for part of one problem, they had those computers
去解决这个问题的不同部分
work on part of a different problem.
因此虽然解决一个问题仍需要花费一个月 但他们可以同时解决
So one problem might still take a month, but they could also solve three or four in the
三到四个其他问题
same amount of time.
而且 对于那些非常重要的计算 他们就用他们的系统同时工作多次解
And for really important calculations, they used their system to simultaneously do the
同样的问题
same problem a whole bunch of times.
那样的话 他们就可以确保答案的正确性
That way, they were sure of the final answer
即使其中的几台计算机在过程中出了错也没关系
even if a couple computers made mistakes along the way.
另外一个早期的进步是在上世纪的五十和六十年代
Another early step came in the 1950s and 60s,
当各院校开始把他们的计算机终端分离出来
when colleges started separating their computer terminals,
一些人可以从自己的终端制作程序
where someone would type their program, from the computers themselves.
这让许多不同的人很容易的体验新的机器
This made it easy for lots of different people to experiment with the new machines while
同时让电路和导管安全远离那些笨拙的手
keeping the circuits and tubes safely away from tinkering hands.
它几乎有点像现在的云计算的早期形式
It was almost like an early form of today’s cloud computing,
从一个用户友好的计算机发出复杂的任务
where a user-friendly computer sends complicated tasks
给在其他地方更高级却不易接近的计算机
to better, less accessible computers somewhere else.
不同的是现在的云使用互联网
Except that today’s cloud uses the Internet,
而在1960是没有互联网的
and in 1960, there was no Internet.
但人们那时就开始考虑它了
But people were starting to think about it.
美国国防部
The US Department of Defense
为了使让科技领先于苏联 创建了高级研究计划
had recently created the Advanced Research Projects Agency,
又被称为ARPA
also known as ARPA,
为了让其科技领先于苏联
to keep its technology a step ahead of the Soviets.
一个叫Joseph Licklider的计算机爱好者
And a computer enthusiast named Joseph Licklider
帮助说服ARPA为一个连接全国的
helped convince ARPA to fund research into
科学家和工程师的计算机网络项目投入研究经费
a computer network connecting scientists and engineers throughout the country.
几个重点院校同意参与合作
A few key colleges agreed to be involved,
1969年ARPA开始建立这个网络
and ARPA started building the network in 1969.
他们称之为 阿帕网络(ARPANET)
They called it ARPANET.
它起初规模很小
It started fairly small,
是一种计算机之间的信息传输服务创立于加州大学洛杉矶分校 加州大学圣芭芭拉分校
as a sort of messaging service between computers at UCLA, UC Santa Barbara
斯坦福大学和犹他大学
Stanford University and University of Utah
但它是这种类型的第一个网络
But it was the first network of its kind.
随着阿帕网络接下来几十年不断成长
And as ARPANET grew over the next couple decades,
它的工程师们会增加功能解决问题
its engineers would add features and solve problems
基本构建了我们在网上做的所有事情
that still shape everything we do online.
阿帕网络最大的创新之一就是通信包交换技术
One of ARPANET’s first big innovations was what’s known as packet switching.
你知道在那些老电影里 当有人给另外一个打电话
You know how sometimes in old movies, when someone wants to phone a friend,
他们得先打给一个总机接线员
they have to to call a switchboard operator first?
需要接线员在那 是因为那些电话是通过一个叫做电路转换的装置工作的
The operator was there because those phones worked by what’s called circuit switching,
如果两个地方之间有一个单一不间断的电路
where signals could only get from one place to another
信号只能从一个地方收到再传向另一个地方
if there was a single uninterrupted circuit between them.
所以接线员的工作基本上就是把线从一个电话拔出 再插进另一个电话线上
So the operator’s job was literally to plug the wire from one phone into the wire from another.
电路转换工作得很棒 如果两个地方之间保持长时间连接
Circuit switching works great if two places stay connected for a long time,
就好像你在打电话一样
like they might, if you’re making a phone call,
这就是为什么大多数电话仍然采用电路转换
which is why most phones still work through circuit switching.
除了现在不再用手动 而用的是自动电路转换之外
except that now the circuits move automatically instead of manually.
但在互联网中使用它 就完全不切实际了
But it would be totally impractical for the internet to work that way.
这样的话 你的计算机一次只能和一台计算机连接
Your computer would only be able to connect to one other computer at a time,
每次连接另一台计算机时就要额外花时间
and it would take extra time whenever you tried to connect somewhere else.
现在一些网站可以把你同时连接到10个
Today, some websites might connect you to ten different computers
来自世界各地不同的计算机
from around the world at the same time.
如果你点击 所有连接到的计算机都要立即作出反应
All of them needing to respond immediately if you click,
还要在同一时间立刻连接并监控
all the while connecting and monitoring
成百上千的其他访问者
hundreds or thousands of other visitors all at once.
那所有地方的电路就得不停地转换
So circuits all over the place would constantly be flipping around,
接上某地方极短时间后马上就得转向连接其他地方
a split second before switching away and connecting elsewhere.
这样是行不通的
It just wouldn’t work.
甚至早在六十年代 工程师们就已经知道
Even back in the 1960s, engineers knew that
计算机发送信息太快了
computers send messages far too quickly to
以至于使用电路转换根本是不切实际的
make circuit switching practical.
所以 他们发明了一个替代产品:通信包交换技术
So instead, they invented an alternative: packet switching,
就是说 不同的计算机用同一组线发送信息
where different computers send messages along the same set of wires
来替代以前的每一条线对应一个
instead of each getting one.
相互通信时 他们只需要发送一条信息 叫做数据包
To communicate with each other, they just send a message, called a packet, along the wires.
每个数据包都有地址标号:
Every packet had a kind of address label:
代表要找的计算机的位置的一串数字
a string of numbers representing the computer where it was headed.
发出信息的计算机就会在
The computer where it started would look up the address on a table
网络上的地址簿大全里查找这个地址
with all the addresses in the network on it,
然后把数据包发到离目的地最近的
and then send the packet toward whatever nearby computer
计算机上
was the closest to the destination.
第二台计算机就会收到数据包 查到目的地地址
That second computer would get the packet, look up the destination address,
然后再把数据包发送到正确的方向
and again, send the packet in the right direction.
这个过程会一次次的重复 直到这个数据包最终到达它要去的地方
This process would repeat over and over until the packet finally got where it was going.
不需要移动电路或电线 没有’一次只能针对一个对话’的要求
No moving circuits or wires, no one-conversation-at-a-time requirement.
阿帕网络从开始就使用的数据包转换 它的数据包都是通过电话线传送
ARPANET used packet switching from the start, and its packets traveled over phone lines.
最初 数据包交换正如设计的那样工作
And at first, packet switching worked exactly as planned.
但是 几年以后
But there were problems over the next couple of years,
随着几十种新计算机从全国各地加入 问题出现了
as dozens of new computers from around the country joined.
由于数据切换系统被设置的方式
Because the way the packet switching system was set up
意味着每台计算机都要随时更新
meant that every computer always had to keep an updated list
所有记录其他计算机的地址簿
of all the other computers’ addresses.
否则 他们不知道把收到的数据包发到哪里
Otherwise, they’d get packets and wouldn’t know where to send them,
或者要发到的地址可能不存在了
or they’d try to send a packet somewhere that might not be around any more.
但这个网络还在变得越来越大
But the network kept getting bigger and bigger,
而且有时候某个计算机的地址可能变更
and sometimes a computer’s address might change
如果他们暂时从这个网络断开连接
if they temporarily disconnected from the network
或者一个连接停止工作了的话
or a connection stopped working.
甚至不同的计算机会最终用上不同的地址录
And different computers ended up with different address books
如果他们的更新不及时的话
if they didn’t update fast enough.
所以阿帕网络的工程师们废弃了那个系统
So ARPANET’s engineers scrapped that system
并在1973年选择了斯坦福作为
and selected Stanford as the official record-keeper
每个人的地址的官方记录
of everyone’s addresses in 1973.
这个快速修复使阿帕网络在70年代继续成长
This quick fix let ARPANET keep growing throughout the seventies,
从1974年的六十台计算机 到1977年 已有超过一百多台了
with sixty computers in 1974 and over a hundred by 1977.
很快 卫星连接了加州和夏威夷
Soon, satellites connected California and Hawaii,
阿帕网络延伸到了一个曾经是世界上最偏远的地方
stretching ARPANET to what had been one of the most isolated places in the world.
然后阿帕网络跳到大西洋的彼岸 把网络延伸到英国和挪威
Then, ARPANET jumped across the pond, extending the network to England and Norway.
到七十年代中期时 阿帕网络并不是唯一的网络
But by the mid-seventies, ARPANET wasn’t the only network in town.
类似的网络出现在世界各地
Similar networks were popping up around the world,
有些网络甚至有更多的计算机
and some had even more computers on them.
但每一个都有自己不同的格式化
But everyone formatted their packets differently,
即使你连接不同的网络 它仍然是件令人头疼的事
so even though you could connect different networks together, it was a real headache.
虽然这个问题在1974年就大部分都已被解决了
The problem was mostly solved back in 1974,
但一直到80年代早期
but it took until the early eighties before
阿帕网络和大部分其他的网络才开始用它
ARPANET and most of the other networks started using it.
这个解决方案就是一套叫做TCP/IP的程序
The solution was a set of programs called TCP/IP,
或叫做 传输控制协议/互联网协议
or Transmission Control Protocol/Internet Protocol
我们现在还在使用
which we still use today.
传输控制协议是一个标准的格式化数据包的方法
The Transmission Control Protocol was a standard way of formatting packets,
这样所有的人都说同样的语言
so that everyone was speaking the same language.
互联网协议是一个标准的地址分配的方式
And the Internet Protocol was a standard way of assigning addresses,
这样就不会混淆数据包被传送的目的地
so there wasn’t any confusion about where packets were headed.
一旦两个网络使用了TCP/IP
Once two networks used TCP/IP,
它们的连接就变得简单多了
connecting them became way easier.
因此 所有不同的网络相连
So all the different networks were connected to one another,
就构成了众所周知的互联网
forming what became known as the Internet
用阿帕网络作为黏合剂把它们都连接起来了。
with ARPANET as the glue holding it all together.
阿帕网络的快速增长 加上连接如此之多的网络
But with ARPANET growing so quickly and connecting to so many other networks,
斯坦福的记录管理员们负荷越来越重
the record-keepers at Stanford were getting overloaded.
那些主机总是在加入和更换地址
Hosts were always joining and changing addresses
并要下载已更新的地址簿
and trying to download the updated address book
斯坦福的目录会偶尔地出现一些
and occasionally the Stanford list would have errors
打乱整个网络通信的错误
that messed up communication throughout the network.
甚至发送电子邮件都成了一件麻烦事
And sending emails was becoming a real pain.
电子邮件是在1971年被发明出来的
Email was invented back in 1971,
到了1973年 多于四分之三的阿帕网络的数据包都是电子邮件
and by 1973 emails made up more than three quarters of ARPANET’s packets.
但不同的计算机有不同的电子邮件程序
But different computers had different email programs,
有些计算机要求发信人和收件人之间经过的每台计算机的清单
and some required a list of every computer it would pass between sender and receiver.
人们就得总在桌上保留一份最新的整个网络的地图
So people had to keep an updated map of the entire network by their desk,
而且他们在发送之前 还要打出电子邮件的路径
and they had to type out the path of their email before they could send it.
阿帕网络上的成百台计算机
And with hundreds of computers on ARPANET and
加上遍及互联网之间的上千台
over a thousand across the Internet, keeping
保留那些地图就变得越来越不可能了
up those maps was getting impossible.
阿帕网络的工程师们意识到
ARPANET’s engineers realized
互联网的整体结构必须要重组
that the entire structure of the Internet had to be reorganized,
所以他们想出了域名系统 或称DNS
so they came up with the Domain Name System, or DNS.
不再用分开每一台主机并按随机顺序储存它们的地址的方法
Instead of separating each host and storing their addresses in a random order,
而是把这些主机安排到不同的区域里
The hosts were arranged into domains.
首先是一级域名 就是那些在每一个网址和邮箱地址
First came the top-level domains — those dot-coms and dot-edus
后面的 .com 和 .edu
at the end of every website and email address.
这些新的一级域名 意味着 在有DNS之前你发一个邮件是 john@example
The new top-level domains meant that instead of sending an email to john@example
那么现在变成 John@example.com了
like you would’ve before DNS, you were emailing john@example.com.
那么在这些一级域名里的每台主机被称为二级域名
Then, within these top-level domains, each host was called a second-level domain.
因此 举个例子 mit.edu 现在的意思就是
So “mit.edu”, for example, now meant “the second-level domain ‘mit’
在一级域名edu內的二级域名–mit
within the top-level domain ‘dot-edu’”.
这个域名结构以计算机可以处理的方式 管理来自世界各地
The domain structure organized all those different hosts from all around the world
所有不同的主机
in a way that computers could handle.
然后 域名系统在互联网上添加了一个全新的网络
Then, DNS added a whole new network to the Internet
它的工作就是追踪地址和连接
whose whole job was to keep track of addresses and connections.
在这个新网络上的一台计算机 有效地储存了域名 .com内的所有地址
One computer on the new network effectively stored all addresses within the dot-com top-level domain,
另外一台计算机有效地储存 .edu 內的所有域名 还有一台储存 .org內的所有地址 那么依此类推
another got all the dot-edus, another got all the dot-orgs, and so on.
然后 其他的新计算机再共同画出整个网络的地图
Then, other new computers collectively mapped out the entire network.
因此 当你想发份电子邮件
So when you wanted to send an email,
你不必自己去查地图并设计好所有的连接
you didn’t have to check your map and plan out all the connections yourself.
那已经变成域名系统的任务–直到现在还是域名系统的工作
That became the DNS’s job — and it’s still the DNS’s job today.
这是为什么当你点击这个视频的时候 你的计算机不知道
It’s why your computer didn’t know how to get a message to YouTube
YouTube怎样接收的信息
when you clicked on this video.
它基本上只是告诉了域名系统服务器 有东西要送到一级域名.com 里
It basically just told the DNS server that it had something for the domain “youtube”
域名是YouTube的地址
within the top-level domain “dot-com”.
然后由域名系统完成接下来的工作
And the DNS server did the rest.
到了二十世纪八十年代末期 国防部意识到
By the late 1980s, the Department of Defense realized
它已经完成了长久以来的目标
that it had long-since accomplished its goal.
起初 他们只想要几台能可靠地相互连接的计算机
Originally, they just wanted a few reliably interconnected computers,
但它们却成为了全球网络的主干 几千所大学 公司
but they ended up serving as the backbone of a global network of thousands of universities, companies, and
还有政府机构 全在相互通话
governments all talking to each other.
所以他们决定结束阿帕网络项目
So they decided to end the ARPANET project,
并且他们需要找个人接管所有这些电线 管理互联网
and they needed to find someone to take over all those wires — someone to run the Internet.
但是谁会被信任到能拥有那么大的权利呢?
But who could be trusted with all that power?
而且互联网这样一个庞大而复杂的系统 可以对公共大众开放吗
And could the internet, this huge complicated system, become accessible to the general public?
这些就是在1989年烦扰互联网最大的问题
These were the big questions plaguing the Internet in 1989,
而且那就是我们在这个系列的下一期要讲的内容
and that’s where we’ll pick up in the next episode of this series.
与此同时 谢谢观看这一期的科学秀
In the meantime, thanks for watching this episode of SciShow,
它是由我们Patreon的赞助人为您提供的
which was brought to you by our patrons on Patreon.
如果你想帮助支持这个节目 请访问patreon.com/scishow.
If you want to help support this show, go to patreon.com/scishow.
而且别忘记去YouTube.com/scishow订阅
And don’t forget to go to youtube.com/scishow and subscribe!

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有关互联网历史的迷你系列视频----第一期

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赖皮

视频来源

https://www.youtube.com/watch?v=1UStbvRnwmQ

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