RIPE NCC starts issuing IPv6 addresses from second /12 block

This summer, IANA assigned a second block of /12 IPv6 addresses to RIPE NCC, the Regional Internet Registry (RIR) for greater Europe and western Asia. Our region is the first of the five to receive a second /12 block for use.

At the moment, anyone in the region who uses IPv6 probably has an address prefix beginning with '2a0', the first /12 block assigned to RIPE NCC. Soon, addresses with '2a1' prefixes will enter use as well. This table shows the IPv6 address blocks so far assigned by the global administrator IANA, and the assignment dates. You'll notice that, until 2005, the assigned blocks (starting '2001:') were considerably smaller than /12. Small is a relative concept, though. As explained in our IPv6 inventory, the IPv6 address space is enormous.

Smart assignment

The fact that RIPE NCC is now on to its second /12 address block should not, therefore, be seen as indicating that we are well on the way to using up all the IPv6 addresses. It's simply a reflection of the way that RIPE NCC allocates blocks within its /12 address space to internet access providers and large organisations that administer IPv6 blocks (Local Internet Registries, or LIRs). A much larger margin is always reserved around each allocated block to allow scope for extension at a later date without making the route tables bigger. For further details, see this blog post.



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