ELI5 How does data sent over the internet know where to go?

r/

How does the system know/figure out what fiber optic cables and what router or tower to send the 1s and 0s through?

Comments

  1. USAF_DTom Avatar

    Routing tables. They store what the device is connected to, and what connects to it. It reads a header on the package of data you’re sending, and sends it out another line that gets it closer to the destination.

    Works pretty much the same way as a post office honestly. Just replace roads with cables and that’s pretty much it, but way faster.

  2. Gnaxe Avatar

    When you send an envelope in the mail, it has an address. When you send a packet of data over the Internet, it has an IP address. The cables connect point-to-point. What goes in just comes out the other end. The magic happens in routers, which are devices that read the address on the packet and route to the right cable. Internet communications typically hop through several routers before they arrive at their destination.