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Contribution Feb 2013 Text Display Screen

Name : REDWIN, Paul
Date : October 10, 2013
Organization : DCMS
Country : UK
Issues : Issue 2

Contribution :


The Council Working Group on International Internet-Related Public Policy Issues invites all stakeholders to provide input on international public policy issues related to:

(a) Unused legacy IPv4 addresses, and

(b) Inter-regional transfers of IPv4 addresses

In responding to this consultation, the UK views public policy issues as requiring input from and decision making by all stakeholders.  The UK notes with concern the apparent duplication that exists in various activities, and believes that new issues should only be initiated if no other study or activity exists.

The UK’s response was agreed using its Multi-stakeholder Advisory Group on Internet Governance (UK MAGIG) with involvement from industry, academia, civil society as well as government. 

Unused legacy IPv4 addresses

The existence of IPv4 legacy space reflects a time in history in the development of the use of IPv4 addresses where the demand that has existed in recent years was not foreseen.  The on-going approach to the IPv4 address management that  resulted in the creation of the  Regional Internet Registries (RIRs), supported by a multi-stakeholder bottom up community approach, has extended the repository of IPv4 addresses available to be allocated.  That this approach has existed, and has overseen an orderly distribution of the final blocks of unallocated IPv4 address space, reflects the commitment  that RIR communities have shown with regard to the policy issues associated with unused IPv4 legacy space.

The original approach taken in assigning IPv4 address resources reflected specific technical drivers prior to the global demand for such resources becoming known.  Many of the addresses allocated during this period were used in a private context, and were never intended to be reachable by everyone.  The increasing demand for IPv4 addresses changed the nature of the approach to IPv4 address resource management, for example with the creation of the RIRs and the policies that their communities developed to ensure an approach to IPv4 address allocation that suited the times.  The evolution in the approach to the remaining IPv4 address allocation has evolved as the needs of the times have evolved. This evolution has extended the lifespan of the IPv4 address pool and allowed for the growth of the Internet.

Whilst IPv4 address space allocated prior to the introduction of the current RIR’s may be considered as being from the same “pot” with the same structure, they are differentiated by the manner in which they have been assigned and the rules that they follow.  It does not mean that legacy address space is unused; it has been assigned, according to the rules of the time. These rules have subsequently evolved, as has the management processes. 

It is fact that as long as legacy space is used for the purposes to which it was allocated then no requirement was identified for such assignments to be considered further.  The nature of the management by which it was allocated meant that putting in retrospective requirements is not possible.

As and when the use of such an IPv4 address changes from its original allocation, processes exist for such allocations to be managed by to-day’s RIR rules.  In this way the communities seek to ensure the updating of the rules of management.  This has been successful with the return of some legacy IPv4 address space to the pool for re-assignment according to-days policies.

Placing an emphasis on utilising IPv4 legacy space, whose availability is understandable limited and cannot be guaranteed, is not a sound basis for maintaining the sustainable growth of IP networks.

Inter-regional transfers of IPv4 addresses

In creating the Regional Internet Registries (RIRs), rules were developed that supported the development of policies to reflect the requirements of their communities and stakeholders.  Such communities and stakeholders are diverse.  This diversity is reflected in the approach that has been taken in the development of interregional transfer policies for IPv4.

The diversity reflects various stages of economic and social use of IP networks, which in turn drives the demand for IPv4 addresses.  Though each RIR was treated equitably in the allocation of recent IPv4 address space, which reflected the consensus of their communities and stakeholders, it is the same stakeholders and communities that decide the inter-regional transfer policy.  The current situation on Inter regional transfers reflects the diversity of the communities.

The UK believes that only through engagement within the current policy making processes can policies be properly developed to meet the requirements of all communities. The focus of public policy for inter-regional transfers of IPv4 addresses should therefore be support for the RIR discussions where the communities have identified a need for inter-regional IPv4 address transfer mechanisms.  Inter-regional transfer is demand driven, responding to the status of IPv4 address allocation.  To date two of the five RIRs have agreed such a policy between themselves.  Of the three remaining RIRs, two (AFRINIC and LACNIC) are unlikely to adopt such a policy in the near future. Their communities have shown no indication to seek such a policy.

RIPE NCC, which serves a region Europe, the Middle East and parts of Central Asia has held consultations about a proposed inter-regional transfer policy but to date has been unable to reach agreement The UK therefore encourages stakeholders (including governments) from across all of the geographic area that falls under RIPE NCC service region, to contribute to RIPE NCC’s consultations on this important issue.  



The UK believes that policy issues relating to IPv4 address legacy space and inter-regional transfers are already being addressed appropriately in the relevant  existing fora and that no further actions are necessary.

With regard to the inter-regional transfer policy, the UK notes the recent activity undertaken by the Regional Internet Registries in consultation with their multi-stakeholder communities, and supports this as the most effective channel through which such policies can be developed and agreed. 

The UK also believes that the priority in the wider discussion about address space remains to foster and facilitate the move to IPv6.