Carrier-grade NAT: The Killer of the "Homelab"

5 days ago

Copy Link

CGNAT (Carrier-Grade Network Address Translation) is used by ISPs to share a single public IPv4 address among multiple customers due to IPv4 address shortages.
CGNAT assigns private IP addresses (100.64.0.0 to 100.127.255.255) to users, breaking inbound connections and making port forwarding impossible.
CGNAT disrupts home server setups by preventing direct internet access to devices behind the NAT, affecting services like FTP and remote desktop.
To check for CGNAT, compare your router's WAN IP with your public IP, check if the WAN IP is in the CGNAT range, or test port forwarding.
ISPs are increasingly adopting CGNAT as IPv4 addresses become more expensive, impacting users who rely on inbound connections for services.
While CGNAT is invisible to most users for outbound activities like browsing and streaming, it fundamentally breaks end-to-end internet connectivity.

Hasty Briefsbeta