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I saw a video on YouTube that explains how the Internet works and it says my packets have an IP address and another IP address is wrapped around the packet at each junction of the internet. So my packet has the IP of my home router, then the home modem, then the DNS server, then whatever routers it takes to get to google.com (for example). Is each IP stored as a separate piece of data in my packet causing it to grow larger as it travels?

Giacomo1968
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user137717
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The video you are linking to attempts to explain how the Internet works very simply. Which is admirable. But there are a lot of face-palm worthy movements in it where simplification veers off into complete miscommunication of the concept.

The concept of how packet works is pretty cringeworthy because it implies that at each stage the packet—which in the video is presented as a piece of candy—gets wrapped in more and more “wrappers” containing network info. That’s not true. And if that was the case, can you imagine how “heavy” a packet would be as it travelled via multiple routers being progressively wrapped more and more? A better explanation can be found on this site; emphasis is mine:

If the packet's ultimate destination is somewhere off the local network, the Ethernet header added by the sending machine will point to a router or switch as its destination address. The router will open the packet, strip off the Ethernet wrapper, read far enough to find the ultimate destination address and re-wrap the packet, giving it a new header that will send it on the next hop of its journey.

So basically—again using the candy analogy—at each hop on the network, the candy “unwrapped” and a new wrapper is placed on it. Or a better analogy is perhaps your data is in an envelope with a letter inside it. At each hop of the network, that letter is opened up—or a sticker is placed on the the envelope—passing network and routing info along until it reaches it’s final destination.

Giacomo1968
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Imagine you want to send a letter. You stick it in an envelope seal it, and then type the address of the final destination.

You give the package to someone (or, drop it in a mailbox) and then the letter is taken to the post office where it is acknowledged with a stamp, and then routed off to its final destination.

On the Internet, this process is a bit complicated because the "post office" only knows about its next post office, and there are many post offices that your envelop has to pass through to get to the final destination.

Each post office knows about a few other post offices around it. Once your letter is received, the address is read, and then either its passed on to the next post office that this one knows about, or if its the final destination the letter is read.

Replace envelope with "packet" and letter with "payload", post office with "router" and you have a good idea of how routing works.

The "candy wrapper" thing is a poor analogy to this; which implies that something is added on top of the packet.

Burhan Khalid
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