The Internet: Packets
The Internet: Packets
There comes a time when you realize that maybe your entire wardrobe won’t fit into your carry-on suitcase—roughly around the third body slam, in our experience. Instead, you’re going to need a whole slew of briefcases to make this five-week vacation work. That might not be the best idea for traveling, but it does make sense for sending information between computers.
Minus the body slams. Please don't body slam your computer.
Every single piece of information that moves around the internet gets to its destination inside a packet. If the name "packet" reminds you of "package," it should, because packets work almost exactly like packages, carefully holding together the internet’s goods as they fly between computers.
More specifically, packets are like the postal service’s flat-rate boxes. They can only carry a specific size of things, but when you put things in them, you know they'll reach their destination fast.
Packets usually hold between 1000 and 1500 bytes. Sound like a lot? It isn't. If you're sending text, you're talking about using eight bytes per letter.
Per. Letter.
To make the most of your packet, you could send 187 letters. That might be more than a Twitter post, but not by much. Plus, if you want to send an image or, dare we say, a video, you'll need much more space. To handle that issue, browsers split up information into oodles of packets to send over the net. Not all of these packets take the same path, but they all eventually reach their destination to get reassembled into the original content.
Each packet has three major parts:
- The header
- The body
- The footer
The header works like a shipping label: it lists both the sender and recipient’s IP addresses, instructions on how to attach this packet to all the others, and the type of information it's holding. The body is filled with—bet you can't guess—the actual data. After that, the footer tells the receiving computer that it's reached the end of the packet.
Whenever you’re listening to your favorite song online or reading through forums of fan theories for your favorite show, you can rest assured knowing that all that stuff arrived in the form of tiny flying bundles of binary that your computer puts together like the world’s fastest jigsaw puzzle solver.