To find internet-connected EtherNet/IP devices, we could scan the internet for devices with an open EtherNet/IP port (TCP or UDP port 44818). Not only would that take a long time, its legal implications are debatable. Thankfully, there are services out there that have done the heavy lifting for us. https://www.shodan.io/ is one of these services.
Quoted from Wikipedia (https://en.wikipedia.org/wiki/Shodan_(website)):
"Shodan is a search engine that lets the user find specific types of computers (web cams, routers, servers, and so on) connected to the Internet using a variety of filters. This can be information about the server software, what options the service supports, a welcome message ...
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