How devices are identified.
WHAT AN IP ADDRESS IS
A number identifying a device on a network.
WHY IT MATTERS
Data cannot reach a device without one.
THE TWO VERSIONS
IPv4, the older and still dominant form, written as four numbers separated by dots IPv6, the newer form, written as groups of characters separated by colons
WHY IPV6 EXISTS
IPv4 addresses ran out.
There are not enough for every device.
WHAT THAT PRODUCED
Techniques for sharing addresses, which is why your devices share one public address.
WHAT YOUR DEVICE HAS
A private address on your local network A shared public address seen by the internet
WHY THAT DISTINCTION MATTERS
Two networks can use the same private addresses without conflict.
But a device on a private address is not directly reachable from outside.
WHAT TO KNOW
Your public address, when troubleshooting or configuring access restrictions.
