You pay a company every month to reach the internet. This lab is about the
people who stopped paying. In the video below, a builder sends a text message from a normal
phone to a phone with no internet connection at all. The last part of the trip is
carried by free radio — and by a twenty-dollar relay hanging from a drone.
你每个月都付钱给一家公司才能上网。这个实验室讲的是那些不再付钱的人。
在下面的视频里，一位创客把一条短信从普通手机发到一部完全没有互联网连接的手机上。
旅程的最后一段由免费无线电承载——由挂在无人机下的一个 20 美元中继完成。
Work in this order: learn the words, watch the
video, then open the machines and say what you see. Everything on this page is
meant to be said out loud.
按这个顺序：先学词，再看视频，然后打开机器，把你看到的说出来。
这一页所有内容都是用来大声说的。
🔤 The words you need
Summary
Twenty-five terms this lab uses, each with a short definition, a longer explanation, and one sentence to say aloud. Learn these first, because every machine below leans on them constantly.
Twenty-five words. Tap 🔊 say it to hear one, and 📖 tell me more
for the real explanation. Learn these first — the rest of the page uses them constantly.
二十五个词。点“🔊 say it”听发音，点“📖 tell me more”看真正的解释。
先学会这些，后面整页都在用它们。
🎤 Speaking drill
Five words at a time. Press the mic, say all five in any order, then check.
一次五个词。按下麦克风，任意顺序说出这五个词，然后检查。
listening
what you say appears here…
🎬 The whole picture — about twenty-two minutes, English subtitles
Summary
A builder puts a public node on the internet, then tests whether a beginner can send a message from a normal phone to a phone with no internet connection at all. The last link is carried by free LoRa radio, through a twenty-dollar relay hanging from a drone. Watch it before you open the machines below.
Watch this before you open the machines. Every machine below takes one moment
from this video apart, so you can drive it yourself.
先看这个再打开下面的机器。下面每台机器都拆解了视频中的一个瞬间，让你亲手操作。
“How to Become Your Own ISP”, by Data Slayer. This video was not made
for this page — it is a real build by a real builder, and that is exactly why it is here.
Watch the original (and the channel) on
YouTube. The English subtitles
come from YouTube's automatic captions, so a few words are imperfect — the captions often
write the radio technology LoRa as “Laura”, which is a person's name. Same sound,
different thing. The 中文 for this lesson lives in the page summaries, not the video.
《如何成为你自己的 ISP》，作者 Data Slayer。这段视频不是为本页制作的——
它是一位真实创客的真实搭建过程，这正是它出现在这里的原因。原片在
YouTube。英文字幕来自 YouTube
的自动识别，个别词不准——字幕常把无线电技术 LoRa 写成人名“Laura”：发音相同，意思不同。
本课的中文在页面摘要里，不在视频里。
🔬 Build the network
Six machines. Break the nodes, drag the sliders, lift the drone.
Then say what you see in English.
六台机器。弄断节点，拖动滑块，升起无人机。然后用英语说出你看到的。
🕸 Two shapes of network
Summary
A star network has a company in the middle, and it dies with that middle. A mesh network has no center, so a message can walk around a broken node. On one road trip, the builder in the video found four hundred fifty-eight mesh nodes already running, built by ordinary people.
Click any middle node to break it. Click it again to repair it.
Then switch the network shape and break the same nodes.
点击任意中间节点把它弄坏，再点一次修好它。然后切换网络形状，再弄坏同样的节点。
The star is what you have now
Your home internet is the edge of a star. Every message you send goes
to your ISP first, whatever its destination. That is convenient — and fragile. One
broken center, one flood, one company decision, and every phone on the star is alone.
你家的网络就是星形的边缘。你发出的每条消息都先经过你的 ISP，
无论目的地是哪里。这很方便——也很脆弱。中心一坏、一场洪水、公司一个决定，
星形上的每部手机就都成了孤岛。
Try this:
In the star, break the ISP. Count who can still talk. Nobody.
Switch to the mesh. Break the same middle node — the message walks around it.
Keep breaking nodes. How many must die before the friend is unreachable?
The star is faster — one hop to the center, one hop out. The mesh pays
extra hops for every message. What it buys with them is survival: there is no single
machine whose death stops the network. The internet's backbone works this way already.
The change is that a node now costs twenty dollars, so you can be part of it.
星形更快——进中心一跳，出中心一跳。网状网络的每条消息都要多走几跳，
换来的是生存能力：没有任何一台机器的死亡能让整个网络停摆。互联网的骨干网早已如此。
变化在于：现在一个节点只要 20 美元，所以你也可以成为其中一员。
The secret of the title — the big companies already mesh
The core of the internet is not a star. The big carriers connect to
each other, in many places, exactly like the mesh above — that is what makes the
internet hard to kill. The star shape only appears at the edge, where the customers
are. So “become your own ISP” really means: stop being a leaf on someone's star, and
become a node that relays for others. That is the whole video in one sentence.
互联网的核心并不是星形。大型运营商在很多地方彼此互联，
正像上面的网状图一样——这正是互联网难以被摧毁的原因。星形只出现在边缘，也就是客户所在的地方。
所以“成为你自己的 ISP”真正的意思是：别再做别人星形网络上的一片叶子，
而是成为一个为他人中继的节点。整段视频用一句话说完就是这个。
📦 One message, six links
Summary
One text message crosses six links that were never designed to work together. A phone on LTE, the public internet, a satellite about five hundred fifty kilometres up, and free LoRa radio become one path. The internet ends at the field bridge, and radio carries the message the rest of the way.
Drag the slider, or press play, and follow the message.
this is the real route from the video拖动滑块或按播放，跟着这条消息走。这就是视频中的真实路线。
paid infrastructure (LTE, internet)satellite (Starlink)free radio (LoRa)
Why this is hard
Each of these links speaks its own language. LTE does not know what
LoRa is. The trick is a shared network layer — Reticulum — that treats every
link as just another interface. To Reticulum, even the whole internet is only one more
temporary cable. If a better path appears by radio, the network can route around the
internet entirely.
这些链路各说各的语言。LTE 根本不知道 LoRa 是什么。诀窍是一个共享的网络层——
Reticulum——它把每种链路都当作一个普通接口。对 Reticulum 来说，
整个互联网也只是又一根临时电缆。如果无线电上出现了更好的路径，网络可以完全绕开互联网。
Why not just use the internet the whole way?
Because the last phone has no internet. That is not a trick —
it is the situation of billions of people some of the time: deep countryside, a
mountain trail, a storm that took the towers down, or simply no money for a plan.
The interesting question was never “can the internet carry a message?” It was: can a
message leave the internet and still arrive?
因为最后那部手机没有互联网。这不是变魔术——
而是数十亿人时不时面对的处境：偏远乡村、山间小路、风暴刮倒了基站，
或者只是没钱买流量。有趣的问题从来不是“互联网能不能送到消息”，
而是：消息能不能离开互联网，仍然送达？
🗼 Height is range
Summary
High-frequency radio travels in straight lines, so trees and hills block it. In this figure the forest is fifteen metres tall, and the link only opens when the antenna clears it. That is the whole reason the relay in the video hangs from a drone.
Drag the slider to lift the antenna. Watch when the link opens — and what
happens to the horizon.
拖动滑块升高天线。注意链路何时打通——以及地平线发生了什么。
height: 2 m·horizon: 5 km·✗ blocked
The cheapest upgrade in radio
In the video, messages stopped getting through at about four
kilometres — too many trees. No new hardware fixed it. Height fixed it: the
same twenty-dollar relay, lifted above the forest by a drone, and the dead link came
back. More power costs money and battery. Height is almost free.
视频中，消息在大约四公里处就传不过去了——树太多。
修好它的不是新硬件，而是高度：同一个 20 美元的中继，被无人机举到森林上方，
死掉的链路就复活了。加大功率要花钱、耗电池；高度几乎是免费的。
How far can LoRa really go?
With line of sight, astonishingly far. The world record for a LoRa
packet is more than one thousand three hundred kilometres, sent from a radio
hanging under a high-altitude balloon. The radio was no stronger than the ones in the
video — it was simply high enough that nothing stood in the way. A satellite is the
same idea taken to the end: an antenna so high it can see half a continent.
在有视距的情况下，远得惊人。LoRa 数据包的世界纪录超过一千三百公里，
由挂在高空气球下的电台发出。那台电台并不比视频里的更强——只是高到没有任何东西挡路。
卫星就是把同一个思路做到极致：一根高到能看见半个大陆的天线。
🧰 The kit that carried the message
Summary
Eight pieces of equipment carried the message in the video. The most important one is a twenty-dollar board that runs the whole network stack by itself. Click each part to learn its name and its job.
The relay board: about $20. A USB LoRa radio: under $100.
The field computer: a Raspberry Pi. Compare the old way: the builder phoned cell
tower companies about hanging one small radio on a tower — $3,000 to
install, a three-year contract, and monthly rent after that. That price gap is
the reason this hobby exists.
中继板约 20 美元；USB LoRa 电台不到 100 美元；
现场电脑是一块树莓派。对比老办法：视频作者打电话问基站塔公司，
想在塔上挂一台小电台——安装费 3000 美元，三年合约，之后每月还要交租金。
这个价格差就是这个爱好存在的原因。
🔐 Locked all the way
Summary
The phone locks the message before it leaves, and only the friend's phone holds the key. Every relay in the middle carries the locked box without being able to read it. Turn encryption off, and every stop on the road reads your mail.
The message is “MEET AT SIX”. Send it both ways and watch what each
relay can see.
消息内容是 “MEET AT SIX”（六点见）。用两种方式发送，看看每个中继能看到什么。
Locks, not promises
The mesh is built from strangers' machines — a server here, a drone
there, a solar node on somebody's roof. You cannot trust them, and you do not have to.
Reticulum encrypts every message by default, end to end. The relays' honesty
stops mattering, because they only ever carry a sealed box. Privacy comes from
mathematics, not from a company's promise.
网状网络由陌生人的机器组成——这里一台服务器，那里一架无人机，
某人屋顶上还有一个太阳能节点。你无法信任它们，也不需要信任。
Reticulum 默认对每一条消息做端到端加密。中继诚实与否不再重要，
因为它们搬运的永远是一个封好的盒子。隐私来自数学，而不是某家公司的承诺。
Encrypted does not mean invisible. A watcher who cannot read your message can
still see that a message passed, when, and how big it was. That information is
called metadata, and it tells a story too. Encryption protects the letter, not
the fact that you posted one.
加密不等于隐身。读不了你消息的旁观者，仍然能看到有一条消息经过、
什么时候经过、有多大。这类信息叫元数据，它同样会讲出一个故事。
加密保护的是信的内容，而不是“你寄过一封信”这个事实。
⚖️ Choose your link
Summary
Every link is a trade between speed, reach, price and survival. Fiber is the fastest and dies with the power grid. LoRa carries about one text message per second, costs nothing monthly, and keeps working when everything else has failed.
A text message is about one hundred bytes. A photo is a million. A
movie is a billion. LoRa cannot carry your movie night, and it never will — but “I am
safe, meet at the bridge” fits in one packet. In a disaster, that packet is worth more
than every streaming service on Earth. Engineering is choosing the right pipe, not
the biggest one.
一条短信约一百字节，一张照片约一百万字节，一部电影约十亿字节。
LoRa 载不动你的电影之夜，永远也载不动——但“我平安，桥头见”一个数据包就装下了。
灾难来临时，这一个数据包比地球上所有流媒体服务加起来都值钱。
工程学是选对管道，而不是选最大的管道。
📌 Points to Remember
The six things worth carrying out of this lab.
这个实验室里最值得记住的六点。
The internet is a network of networks. An ISP is just the company standing
between you and it — and standing there is a job you can learn.
互联网是网络的网络。ISP 只是站在你和它之间的那家公司——
而“站在那里”是一份你可以学会的工作。
A mesh has no center. Break a node and the message walks around it. Break the
center of a star and every phone on it is alone.
网状网络没有中心。弄坏一个节点，消息会绕过它；
弄坏星形网络的中心，上面的每部手机都成了孤岛。
Height is range. Radio travels in straight lines, so a twenty-dollar relay
lifted above the trees can revive a dead link. The drone is a flying antenna mast.
高度就是距离。无线电沿直线传播，所以一个被举到树顶上方的
20 美元中继就能救活一条死链路。无人机就是一根会飞的天线杆。
Encryption locks the message at your phone. Strangers' relays carry the sealed
box without reading it — but they can still see that a box went past.
加密在你的手机上就把消息锁好。陌生人的中继搬运这个封好的盒子却读不了它——
但它们仍然看得见有一个盒子经过。
Every link is a trade. Fiber is fast and dies with the power. LoRa carries one
text per second, costs nothing, and survives. Match the pipe to the job.
每种链路都是一种交换。光纤快，却随电力一起瘫痪；
LoRa 每秒一条短信、零月费、打不垮。要按任务选管道。
One message crossed LTE, the internet, a satellite and LoRa — four networks
never designed to work together — as one encrypted path. That is the next era of
communication, and it is being built by ordinary people.
一条消息跨越了 LTE、互联网、卫星和 LoRa——四种从未被设计成协同工作的网络——
走完了一条加密路径。这就是通信的下一个时代，而它正由普通人亲手搭建。
Thank you for working through it —
and see you in the next lab.
感谢你完成这一课——我们下个实验室见。
🖼️ Credits
The overview video is
“How to Become Your Own ISP” by Data Slayer, hosted here for this lesson —
the original, and much more like it, is on
his YouTube channel. It is real
footage of a real build; nothing in it was staged for this page. Every diagram on
this page is drawn by the page itself, in code — a mesh network is a shape, not an object,
and a shape you can operate teaches more than a photograph of one.
概览视频为 Data Slayer 的《如何成为你自己的 ISP》，为本课托管于此——
原片及更多同类视频在他的 YouTube 频道。
视频是真实搭建的真实记录，没有任何摆拍。本页所有示意图都是页面用代码自己绘制的——
网状网络是一种形状而不是一件物品，而一个你能亲手操作的形状，比它的照片更能教会你。