At the beginning of November 2024, the Internet Assigned Numbers Authority (IANA) allocated a second /12 to APNIC, 2410::/12 — the block adjacent to APNIC’s existing allocation of 2400::/12. This is only the second time APNIC has applied to IANA for a /12 since 2006 under the global address policy processes and reflects the continued pace of growth of IPv6 in the Asia Pacific community. APNIC has delegated IP ranges from our original holdings and subsequently our first /12 block for over 18 years.
Since adopting the ‘sparse allocation‘ framework in 2012, which balanced headroom for allocations and address conservation, APNIC has managed seven initial allocations made under 2000::/3 from IANA in a ‘slow start’ policy since 1999, plus 2400::/12 made subsequently in 2006 under a new global address policy which applied to all the RIR who each received a /12 at this time. With an approved request for a large allocation of /17 of space, APNIC did not have a single extent large enough to meet this request which led to APNIC making a request for the next block of addresses, as a subsequent allocation from IANA.
The pace of delegation has reflected differing needs across time, with a steady background of /48 and /32 allocations and intermittent allocations of significantly more space. The /17 that triggered the IANA delegation of 2410::/12 represents the single largest delegation APNIC has made.
IPv6 usage in the APNIC region
In the APNIC region, most allocations are single /32 blocks, meeting routing needs efficiently. Only 10.62% of IPv6 holders have required subsequent allocations, indicating that IPv6 address policies effectively support the routing community without imposing burdens or limiting access.
APNIC’s largest single delegation to date is this new one, a /17 block, allocated to Huawei as a Singaporean registrant. This allocation supports global deployment of cloud services and content distribution, sourced from newly delegated space.
APNIC isn’t the largest holder of IPv6 space. RIPE NCC leads with over 37%, followed by ARIN at 28.5%. APNIC holds 28.2%, LACNIC 3.5%, and AFRINIC 2.3%. These shares reflect regional network complexity, market maturity, economic size, and delegation numbers.
Delegating the new block
The request was made using a shared IANA-RIR template to ensure policy alignment, resulting in the block’s delegation and updates to ip6.arpa for DNS PTR authority. APNIC has also updated its RPKI systems to support allocations and issue certificates under the new /12.
The existing 2400::/12 and new 2410::/12 allocations are co-aligned in the global address space and can be collectively referred to as 2400::/11, a single prefix. However, due to differing instantiation dates, they are tracked separately in whois, RDAP, and NRO delegated statistics, covering allocations, available space, and reserves. Following the release of a /17 from the new range, smaller prefixes are now listed as available to account for the remaining space.
APNIC will continue to employ the conservative ‘sparse’ delegation policy, using a ‘binary chop’ method to maximize free space between allocations. This approach ensures delegates can request co-aligned blocks for future needs and minimize Border Gateway Policy (BGP) prefix counts if desired. Unlike sequential allocation, this method maximises space availability and supports efficient routing management.
For logistical reasons, APNIC sub-divides the 2400::/12 address space into ‘small’ and ‘large’ allocations. The small delegation range is between /32 and /24 and ‘large’ from /28 to /16. Whenever possible, a delegation is made from the small range. Some objects are larger than /28 in the regular range and some smaller than /24 in the larger range, creating an overlap in preferences within these size bands. This overlap is driven by subsequent allocations and the goal of maximizing the reserve space between allocations.
Noting that the /17 has already come from the 2410::/12 range, APNIC will begin making routine allocations from the newly delegated range in due course. For more information on the resources administered by APNIC, see ‘Resource ranges allocated by APNIC’.
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