There are more than one billion computers in the world, and each individual computer needs its own IP address whenever it’s online. The TCP/IP protocols (our computers’ built-in, internal networking software) include a DHCP protocol. It automatically assigns and keeps tabs of IP addresses and any “subnetworks” that require them. Nearly all IP addresses are dynamic, as opposed to “static” IP addresses that never change.
DHCP is a part of the “application layer,” which is just one of the several TCP/IP protocols. All of the processing and figuring out of what to send to whom happens virtually instantly.
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