What Is IPv6? Differences from IPv4 and Notation
IPv6 is the 128-bit addressing scheme created to overcome IPv4 exhaustion. Its address space (about 3.4×10³⁸) is effectively unlimited, so every device can have a public address without NAT.
⚠️ In the current deployment this server reaches the Internet over IPv4 only, so the self-IP shown on the home page is IPv4 today. IPv6 is covered in these articles. The Subnet calculator and IP converter run in your browser, so they accept IPv6 input.
Notation and Zero Compression
IPv6 is written as eight 16-bit groups of hexadecimal separated by colons.
2001:0db8:0000:0000:0000:ff00:0042:8329
Compression rules:
- Leading zeros in a group may be dropped →
2001:db8:0:0:0:ff00:42:8329 - One run of all-zero groups may collapse to
::→2001:db8::ff00:42:8329
Paste an IPv6 address into the IP converter to switch between the expanded and compressed forms.
Key Differences from IPv4
| Item | IPv4 | IPv6 |
|---|---|---|
| Bit length | 32 | 128 |
| Notation | Dotted decimal | Colon hex |
| Broadcast | Yes | No (uses multicast) |
| Autoconfig | DHCP | SLAAC / DHCPv6 |