IPv4 vs IPv6: What's the Difference?
Two Generations of IP
IPv4 and IPv6 are two generations of the Internet Protocol. The world is gradually migrating from IPv4 to IPv6.
Key Differences
| Item | IPv4 | IPv6 |
|---|---|---|
| Address length | 32 bits | 128 bits |
| Address space | ~4.3 billion | ~3.4×10^38 |
| Format | Dotted decimal, e.g. 192.168.1.1 | Hexadecimal, e.g. 2400:3200::1 |
| Typical ranges | 10/8, 192.168/16 | fc00::/7 private, fe80::/10 link-local |
| Configuration | DHCP | SLAAC supported |
Why IPv6
IPv4 addresses have run out, which is why NAT became common. IPv6 provides an enormous address space so every device can have a globally unique public address.
How to Check IPv6 Support
- Open this site: if your public IP is hexadecimal, your network supports IPv6.
- On Windows, run ipconfig and look for addresses starting with 240e, 2408, 2409 etc.
- IPv6 test sites can show your connectivity level.