What is carrier-grade NAT?
Carrier-grade NAT places address translation inside an internet provider’s network.
Website: https://zenshield.com/glossary/cgnat
Carrier-grade NAT
Carrier-grade NAT places address translation inside an internet provider’s network.
On this page
Multiple customers can share public IPv4 address space. This is different from only having a private address behind your own home router, and it can matter when an application needs an incoming connection.
A practical example
If you forward a port on a home router but an external connection still cannot reach the device, a second translation layer is one possibility. It is not the only explanation: firewall rules, the application and the test itself also matter.
What to check
Ask the provider whether your service uses shared addressing and what options it offers for the task you need. RFC 6598 reserves 100.64.0.0/10 as shared address space, but an address observation alone should not replace confirmation of the provider’s setup. Explain whether you are hosting a service, joining a game or simply browsing.
What it does not tell you
A VPN subscription does not automatically provide an incoming public address or port forwarding. Check that exact feature before choosing a service. Zenshield does not claim a verified port-forwarding capability here.
Read the technical reference for the underlying definition. For a connection that is failing now, use the troubleshooting guide. To choose an app, follow the VPN selection worksheet.
Sources
What is my IP?Check your VPN is working
On this page
Keep exploring
What is my IP?Check your VPN is working
Keep exploring
What is NAT? ↗
Network address translation changes address information as traffic passes between networks.
What is a public IP address? ↗
A public IP address is used on the internet-facing path of a connection.
What is IPv4? ↗
IPv4 is an Internet Protocol version that uses 32-bit addresses, commonly displayed as four numbers separated by dots.