The proposal, 'Reserving /10 IPv4 address space to facilitate IPv6 deployment', has been sent to the Policy SIG for review. It will be presented at the Policy SIG at APNIC 28 in Beijing, China, 25-28 August 2009. We invite you to review and comment on the proposal on the mailing list before the meeting. The comment period on the mailing list before an APNIC meeting is an important part of the policy development process. We encourage you to express your views on the proposal: - Do you support or oppose this proposal? - Does this proposal solve a problem you are experiencing? If so, tell the community about your situation. - Do you see any disadvantages in this proposal? - Is there anything in the proposal that is not clear? - What changes could be made to this proposal to make it more effective? Information about this and other policy proposals is available from: http://www.apnic.net/policy/proposals Randy, Jian and Ching-Heng ________________________________________________________________________ prop-078-v001: Reserving /10 IPv4 address space to facilitate IPv6 deployment ________________________________________________________________________ Authors: Terence Zhang Yinghao <zhangyinghao at cnnic dot cn> Jane Zhang <zhangjian at cnnic dot cn> Wendy Zhao Wei <zhaowei at cnnic dot cn> Version: 1 Date: 29 July 2009 1. Introduction ---------------- This proposal seeks to ensure some small blocks of IPv4 space will remain available to LIRs for a long time to ease the co-existence of IPv4 and IPv6 and to facilitate IPv6 deployment. It is proposed that when APNIC receives its last /8 IPv4 allocation from IANA, a contiguous /10 IPv4 block will be set aside and dedicated to facilitate IPv6 deployment. 2. Summary of the current problem ---------------------------------- The IPv4 address pool is expected to be depleted in the near future, but the Internet will still use IPv4 for many years during the adoption of IPv6, during this period, LIRs will need to connect to the IPv4 Internet while they deploy services using the IPv6 Internet. APNIC's current "final /8" policy  prevents any one organization consuming too many IPv4 address from the final /8, which ensure new LIRs can participate in the IPv4 Internet. However, the final /8 policy does not require LIRs to deploy IPv6. Therefore, it is possible that LIRs use those allocated address entirely for IPv4 services. Later, when they intend to deploy IPv6, they will have no chance to get another IPv4 allocation from APNIC under the "final /8" policy, even if there are a certain amount of unallocated IPv4 addresses remaining in APNIC's pool. Instead, the LIR would have to re-organize their IPv4 network to set aside some addresses. This would impact their progress in IPv6 deployment. To remedy this problem, this policy proposal seeks to encourage LIRs to deploy IPv6 and ensure IPv4 space will remain available for LIRs' IPv6 deployment. 3. Situation in other RIRs --------------------------- ARIN has adopted a similar policy: 2008-5: Dedicated IPv4 block to facilitate IPv6 Deployment https://www.arin.net/policy/proposals/2008_5.html RIPE has similar policy proposal under discussion: 2009-04: IPv4 Allocation and Assignments to Facilitate IPv6 Deployment http://www.ripe.net/ripe/policies/proposals/2009-04.html AfriNIC and LACNIC currently have no similar policies or proposals. 4. Details ----------- It is proposed that when APNIC receives its last /8 IPv4 allocation from IANA, a contiguous /10 IPv4 block from the /8 will be set aside and dedicated to facilitate IPv6 deployment. Allocations and assignments from this dedicated /10 block must be justified by immediate IPv6 deployment needs; examples of such needs include: IPv4 addresses for key dual stack devices, NAT-PT or NAT464 translators, etc. The size of each allocation from this /10 block is /24, or APNIC's minimum allocation size in force at time of the allocation, which ever is smaller. Each LIR may apply for and receive the specified allocation size regardless of LIR size or intended membership tier. In order to receive a first allocation or assignment under this policy: 1. The applicant must demonstrate immediate IPv6 deployment needs, especially for IPv6 to IPv4 internetworking. 2. The applicant must either have existing IPv6 addresses or valid application for IPv6 addresses. 3. The applicant must be a current APNIC account holder or a member of an NIR. In order to receive subsequent allocation or assignment under this policy: 1. The applicant must demonstrate immediate IPv6 deployment needs, especially for IPv6 to IPv4 internetworking. 2. The applicant may not have received resources under this policy in the preceding 12 months. 3. Previous allocations/assignments under this policy must be strictly used to facilitate IPv6 deployment, and the utilization rate is higher than 75%; 4. The utilization rate of previous allocations/assignments of other IPv4 addresses allocated from APNIC must reach 80%, or APNIC's current IPv4 allocation policy required utilization rate at the time of the allocation. 5. The applicant must be a current APNIC account holder or a member of an NIR. Allocations under this policy do not affect an LIR's eligibility to apply for IPv4 addresses under the "final /8' policy", and vice versa. 5. Pros/Cons ------------- 5.1 Advantages: - This proposal will encourage IPv6 deployment as it ensures LIRs can receive dedicated IPv4 address space from the APNIC if they have an immediate need to deploy IPv6. - The dedicated /10 block provides 16,384 allocations, which ensures that no organization lacks IPv4 address space for IPv6 deployment for many years. 5.2 Disadvantages: - There is a remote possibility that, after setting aside one /10 under this proposal, the remainder of the last /8 may be used up. If that were to happen, LIR would need to have immediate IPv6 deployment needs to qualify for IPv4 addresses from APNIC. However, with 12,288 possible allocations from the current minimum allocation (at time of writing), and considering that the projection of APNIC members in 2013 is 4000, it is not likely the 12,288 allocations will be used up. In addition, if it does happen, applying for IPv4 address without any intent to deploy IPv6 is not practical. Also, the size of allocation under this policy (/24) can be reduced to suit future needs, if necessary. 6. Effect on APNIC members --------------------------- This proposal allows APNIC LIRs (existing and new) to receive dedicated IPv4 address space from APNIC to facilitate IPv6 deployment. 7. Effect on NIRs ------------------ This proposal has no direct impact to NIRs. NIR members (existing and new) can receive dedicated IPv4 address space from APNIC to facilitate IPv6 deployment. 8. References -------------  See section 9.10, "Policies for IPv4 address space management in the Asia Pacific region" http://www.apnic.net/policy/add-manage-policy.html#9.10 9. Appendix A ------------- Reason for reserving a contiguous /10 The IPv6 Internet may take a long time to develop, and since IPv4 and IPv6 may co-exist for many years, the demand for IPv6 to IPv4 internetworking will be sustained for many years. The intention of the proposal is to stimulate native IPv6 deployment as much as possible, while supporting the need for IPv6 networks to communicate with the IPv4 world. The current policy for allocations from the "final /8" will provide 16384 allocations. Setting aside a /10 from that /8 will reduce the allocations to 12288. Since currently APNIC has about 2000 members and is projected to have 4000 members in 2013, it is feasible to set aside a /10 to encourage and ensure IPv6 deployment. The dedicated /10 block itself can provide 16384 allocations with the /24 maximum allocation size. This, in addition to the requirements of a 12-month interval between allocations from this block and a 75% utilization rate for previous allocations from this /10 before additional allocations from this block can be made, would prevent hoarding and ensure this pool will last many years. Reason for /24 allocation size Allocations under this policy are mainly for IPv6 to IPv4 internetworking purpose, such as IPv4 addresses for key dual stack devices, NAT-PT or NAT464 translators, etc. Therefore, we need only a few addresses to do the job. In most cases we can foresee, a /24, or even a /27, can perfectly satisfy the deployment needs for one organization. The reason we choose /24 is we do not want to create longer prefixes in the Internet routing table just because of this policy. Based on knowledge of current Internet's route filtering culture, we believe /24 is the most generally accepted longest prefix currently. Of course, it is possible routing practices will change when we are running out of IPv4. Therefore, in the future, if longer route prefixes are more generally accepted, or a smaller minimum allocation size takes effect, we can certainly reduce the size of allocation under this policy to suit future needs, and ensure more allocations from this block are possible. Finally, a relatively larger allocation size will minimize the possibility of an organization getting multiple non-contiguous small blocks in multiple allocations.