Give an iPhone 7 and some AirPods to a Victorian child, and watch them get burned at the stake just for holding that stuff.

給一個維多利亞時代的孩子一部iPhone 7和一些AirPods，然後看著他們因為攜帶這些東西而被綁在柴火堆上燃燒。

Like we're for real just here on a big rock with sticks and water and made Bluetooth from that.

就像我們真的只是在這顆大石頭上，手持著木棍和水，卻從中製造出了藍牙技術。

What the flip is going on here?

這到底是怎麼回事？

Well, it's actually quite simple.

其實，這很簡單。

No, it's not.

不，不是這樣的。

That was a lie.

那是個謊言。

This stuff is wack.

這東西太奇妙了。

To begin, your phone and earbuds communicate with light.

首先，你的手機和耳機通信是透過光的方式。

Not this light, not this light either.

不是這道光，也不是這道光。

It's like a freaky sort of light.

是一種怪異的光。

On the electromagnetic spectrum, the human eye can see 400 to 600 nanometers.

在電磁光譜中，人眼可以看到 400 到 600 納米的範圍。

Zoom out and you'll notice the human eye is actually blind.

放大一點，你會注意到人眼實際上是盲目的。

The light that Bluetooth uses is over here, specifically 121 millimeters through 124 millimeters.

藍牙使用的光在這裡，具體在121毫米到124毫米之間。

Not only is this light invisible to the human eye, but the waves are so long that it can pass through walls like how visible light passes through glass.

不僅這種光是肉眼看不見的，而且波長如此之長，以至於它能穿過牆壁，就像可見光穿過玻璃一樣。

Cool, but how does light allow me to listen to Shakira?

很酷，但是光怎麼讓我聽到 Shakira 的音樂呢？

1s and 0s. Say 121 millimeters is purple and 124 millimeters is green.

因為1和0。比方說，假設121毫米代表紫色，124毫米代表綠色。

If your phone wants to send a one to your earbuds, your antenna turns purple.

如果你的手機想要向你的耳機傳送一個1，你的天線就變成紫色。

The antenna on the earbuds sees this and tells the microchip in the earbuds.

耳機上的天線感知到這一點，然後通知耳機中的微芯片。

"Hey, it's purple."

「嘿，這是紫色的。」

And then the microchip writes down a 1.

然後，微芯片會寫下一個 "1"。

If the phone wants to send a 0, the antenna turns green, and the same thing happens.

如果手機想要發送一個0，天線就變成綠色，同樣的事情發生。

This happens about a million times a second.

同樣的事情每秒鐘都會發生一百萬次。

Ok.

好的。

So now we know how to communicate.

現在我們知道如何溝通了。

But this brings up about a million problems.

但這也帶來了無數的問題。

For example, if my bro is next to me listening to Taylor Swift, while I'm hearkening to the songs of Shakira, like a real man,

例如，如果我的兄弟在我旁邊聽泰勒絲的歌，而我卻像個真正的男人一樣聽夏奇拉的歌，

how does my ear buds know to ignore the Taylor Swift and only play Shakira?

我的耳機怎麼知道不聽泰勒絲的歌，只放夏奇拉的歌？

Well, this problem has a couple of solutions.

這個問題有幾個解決方案。

First of all, it's not actually just purple and green.

首先，它實際上不只是紫色和綠色。

There are 79 separate sections or channels within the range of purple and green.

在紫色和綠色的範圍內，有79個獨立的部分或通道。

Each channel has its own specific wavelength for 1 and 0.

每個通道都有自己特定的波長表示1和0。

So while you might be in channel 37, your bro could be in channel 73.

是以，當你在頻道 37 時，你的兄弟可能在頻道 73。

But what if there are 158 different phones and earbuds playing music in the same place, 2 for each channel?

如果有158個不同的手機和耳機在同一地方播放音樂，每個通道有2個的話，該怎麼辦呢？

First of all, the lag would be absolutely scandalous, but still, your earbuds would limp along, playing the one and only Shakira and no one else's garbage.

首先，延遲會非常令人震驚，但是即便如此，你的耳機還是會堅持下去，播放唯一的夏奇拉音樂，而不是其他人的垃圾。

How? Well, this is when we finally talk about how your headphones and phone pair.

怎麼做到的？那麼，這就是我們終於要談論你的耳機和手機如何配對的時候。

Think of your earbuds as being a lock.

把耳機想象成一把鎖。

When you click the pair button on set earbuds, it actively sends out a key through its antenna.

當你按下耳機上的配對按鈕時，它會主動通過天線發送一個密鑰。

Then, in your phone settings, you can see all the keys being sent out and your phone can say, "Key number 37948, I choose you."

然後，在你的手機設置中，你可以看到所有被發送出的密鑰，你的手機會說：「密鑰編號37948，我選擇你。」

What then happens is at the beginning each package of 1s and 0s your earbuds, change its lock and using the old key, it gives a new key to your phone.

然後，在開始時，每個包含1和0的數據包，你的耳機會使用舊密鑰更換它的鎖，並將一個新密鑰提供給你的手機。

So your earbuds technically can hear your bro's Taylor Swift playing if it's in the same channel.

所以，從技術上來說，如果你的兄弟在同一個通道上播放泰勒絲的音樂，你的耳機理論上是可以聽到的。

But since it doesn't have the correct key, it not only ignores it completely, but it actually has no idea how to read it because the key is an encryption for the rest of the message.

但由於它沒有正確的密鑰，它不僅完全忽略它，而且實際上不知道如何讀取它，因為該密鑰是對其餘消息的加密。

Now another question arises. Couldn't someone just intercept and then decrypt of all of what's being transmitted between your phone and headphones?

現在又出現了另一個問題。難道有人不可以截取然後解密在你的手機和耳機之間傳輸的所有內容嗎？

Well, some of the engineers probably watched a little Einstein as a kid because there's a genius solution to this problem.

一些工程師可能在孩童時期看過一點愛因斯坦，因為對這個問題有一個天才的解決方案。

Your phone and earbuds don't just stay in one channel.

你的手機和耳機不會只停留在一個頻道。

They do something called frequency hopping.

他們採取一種被稱為「跳頻」的方法。

They hop around from channel to channel and do this about 1600 times every second.

它們在各個通道之間不斷跳躍，每秒約跳躍1600次。

So an eavesdropper might be able to listen in for a teeny fraction of a second, but then you change channels and they would have no way of knowing what channel you went to.

因此，竊聽者可能能夠聽取極短暫的時間，但然後你更換通道，他們就無法知道你轉到了哪個通道。

But then how do both your phone and earbuds know what channel to go to?

但是你的手機和耳機是如何知道要轉到哪個通道的呢？

Well, when your phone initially connects and says, "Key number 37948, I choose you," within that message, it picks out a sequence and sends that information encrypted over to your headphones before any sound is even playing.

當你的手機最初連接並說：「密鑰編號37948，我選擇你」時，在該消息中，它選擇一個序列並在任何聲音播放之前將該信息加密傳送到你的耳機。

This way, your phone and headphones are the only things that know what channel they're going to go to next.

這樣，你的手機和耳機是唯一知道下一個要轉到哪個通道的設備。

So, yeah, not too complicated.

所以，是的，不太複雜。

Now, you should be able to take sticks, rocks and water and create some Bluetooth.

現在，你應該能夠用樹枝、石頭和水創造出一些藍牙了。

You're welcome.

不客氣。

That's gonna cost you one subscribe and let me just flip this bad boy around tips in the form of likes are appreciated.

這要收取你一個訂閱，讓我把這個訊息傳遞出去，點贊的形式將不勝感激。