IPv6
While IPv4 has a fixed limit of around 4 billion IP addresses, IPv6 will have exponentially more, on the magnitude of around 340 billion billion billion billion (3.4×1038).
- Next gen ip protocol
As the 4 billion IPv4 addresses run out sometime early next decade (current estimates: 2011-2012), the Internet will stop growing if we do not find ways to tackle the exhaust. The successor to IPv4 - IPv6 - allows 340 undecillion addresses or more than 50 billion billion billion per person on earth.
PI - Provider independent IP block Importance for dual homing.
Address plan examples (2015)
- Only first half /64 used, last half of ipv6 is for host-ID
- Big company's may be issued with /32 IPv6 space.
- Best practice is to use /48 for a site, with /64 for individual subnet's.
- Two main chains of thought for sub-netting
- Regional, e.g. Country, Site, Building, allowing for summerisation
- Functional, e.g Function, Site etc. allowing for security rules based on a prefix mask.
/40 L1 |
/48 L2 |
/56 L3 |
/64 |
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Customer |
Sites |
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