The number of possible unique addresses was far smaller than what people predicted would be needed shortly, and that prediction came true. When the internet first began its superfast growth over two decades ago, the addresses used came from a relatively small range, using the IP version 4 (IPv4) standard. That’s true on a LAN or within top-level internet data exchanges, and whether it’s a $10 million router or an addressable smart lightbulb. Here’s why.Įvery device that communicates over the internet needs a unique internet protocol (IP) address, a number that is used by routers to package and send data to the right recipient. This conflict prevents your computer from accessing some of the local network and from reaching the internet. That message: “Another device is using your IP address.”
In this case, your Mac is alerting you to a problem that may be of your making or might involve your Wi-Fi gateway or broadband modem.
There’s a particular message that macOS displays in limited cases that perplexes people, because it’s the sort of low-level bubbling up that Apple generally takes care of. Internet networking involves a lot of alchemy, and I confess to occasionally dropping an eye of newt (or an IP of newt) into a boiling pot to fix problems on my local network.
