Glossary · Networking
IPv4
The original internet addressing scheme, with about 4.3 billion possible addresses, now so scarce that providers ration and share them.
IPv4 is the addressing system the internet grew up on, written as four numbers like 192.0.2.10. Its ceiling is roughly 4.3 billion addresses, which sounded limitless in the early 1980s and ran out in practice years ago. That scarcity, not any technical flaw, is the defining fact about IPv4 today.
Scarcity drives everything downstream. Addresses cost real money on a transfer market, providers hand out fewer than one per customer, and carrier-grade NAT exists specifically to hide many households behind a single public IPv4. For proxies this scarcity is why a clean IPv4 address carries value.
It is not going away. Despite IPv6 existing for decades, most of the consumer internet still reaches sites over IPv4, so it remains the address type that matters for almost all proxy work.
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