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What is Carrier-Grade NAT — diagram showing home networks, ISP and internet

Why CGNAT exists — IPv4 scarcity, shared address space, operational goal

What changes with CGNAT — browsing works, no unique IP, some services affected

Am I behind CGNAT — 3-step check: WAN IP, public IP, compare

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CGNAT lets an ISP share one public IPv4 among multiple customers.

NetworkingOctober 15, 2026

What is Carrier-Grade NAT?

🌐 Most ISPs now share a single public IPv4 address across multiple households, here's what that means, what breaks, and how to check if you're behind it. 🔍