IPv6
- Subnets should always be /64s
- Use SLAAC whenever possible, avoid DHCP
- Using nibble-aligned (4 bit) prefixes makes things easier
fe80::/10 are link-local addresses - Gross, it's NOT nibble-aligned, which means this range is
fe80:: to febf::. So anything that starts with fe8, fe9, fea and feb.
- DHCPv6 prefix delegation is a common way ISPs hand out IPv6 ranges.
How Many /64s
| Prefix | /64s | Subnet Bits |
| /48 | 65,536 | 16 |
| /49 | 32,768 | 15 |
| /50 | 16,384 | 14 |
| /51 | 8,192 | 13 |
| /52 | 4,096 | 12 |
| /53 | 2,048 | 11 |
| /54 | 1,024 | 10 |
| /55 | 512 | 9 |
| /56 | 256 | 8 |
| /57 | 128 | 7 |
| /58 | 64 | 6 |
| /59 | 32 | 5 |
| /60 | 16 | 4 |
| /61 | 8 | 3 |
| /62 | 4 | 2 |
| /63 | 2 | 1 |
| /64 | 1 | 0 |