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Assessment Criteria for IPv6 Allocations

Who can request an allocation of IPv6 address space?

To receive an allocation of IPv6 address space from the RIPE NCC, an organisation must:

  • Be a member of the RIPE NCC
  • Have a plan for making sub-allocations to other organisations and/or end site assignments within two years

If these criteria are met, an LIR immediately qualifies for an IPv6 allocation up to a /29 without any further justification required. This also applies if extending an existing smaller allocation up to a (maximum) /29 in size.

What criteria are used when evaluating an initial IPv6 allocation larger than a /29?

(1) Amount of users / extent of infrastructure

An initial IPv6 allocation request is evaluated by first looking at the scope and size of the organisation's customer base and internal infrastructure. The LIR should provide comprehensive documentation showing the amount of end sites, as well as the subnet size required for each end site. In addition, the LIR should provide documentation showing the need for IPv6 address space within their own network (core, data centre, POP etc.).  

(2) Hierarchical and geographical structure / planned longevity

Once the size and scope of the organisation's network has been defined, the RIPE NCC can consider up to one extra bit for hierarchical/geographical structuring of the organisation or for planned longevity of the allocation. These considerations are mutually exclusive so it is not possible to receive extra bits for both.  

(a) Hierarchical and geographical structure

Expanding the assessment criteria to include the hierarchical/geographical structure of the organisation enables LIRs to make an addressing plan which allows for aggregated addressing of future assignments within their network.  

For example, an organisation may provide services to eight separate end sites in "City 1".  Providing a /48 assignment to each end site would justify a total usage of /45 per city: 

City 1 
/48      /48      /48      /48      /48      /48      /48      /48 
|------------------------------ /45 ------------------------------|

Now let's assume that this organisation provides the same service in a further seven cities in this region. They would justify a total usage of /42 for the region: 

Region 1 
City 1  City 2  City 3  City 4  City 5  City 6  City 7  City 8 
/45     /45     /45     /45     /45     /45     /45     /45 
|----------------------------- /42 ---------------------------|

Finally, let's assume that the organisation provides the service(s) throughout the country and are currently present in eight regions. They would justify a total usage of /39 for the country: 

Country 1
Region1   Region2   Region3   Region4   Region5   Region6   Region7   Region8
/42       /42       /42       /42       /42       /42       /42       /42 
|----------------------------------- /39 -----------------------------------|

Based on the amount of users and the extent of the infrastructure, this would be the maximum amount of IPv6 address space that the LIR could justify for this service.  But what happens when the organisation starts providing services to a new end site in City 1, Region 1?  Must they renumber their network or use a non-contiguous address block?  

Fortunately, the answer to this question is "no"; they do not have to renumber their network or use a non-contiguous address block. Taking the structure of the organisation into account, the RIPE NCC can consider up to one extra bit per hierarchical or geographical segmentation.  

(b) Planned longevity

If the hierarchical or geographical structure of the organisation is not applicable, then the RIPE community has also allowed expansion of the assessment criteria to include the planned longevity of the allocation. This also enables LIRs to make an addressing plan which allows for aggregated addressing of future assignments within their network.  

For example, based on the amount of users and the extent of their infrastructure, an organisation providing Internet connectivity to 500,000 home users (with a /48 assignment per user) would justify a total usage of /29.  However, if the organisation can provide comprehensive documentation about the past growth of its services, the RIPE NCC can consider reasonable future growth for a timeframe in line with that for which the historical growth was documented.  

Where a larger initial allocation is requested to support either the hierarchical/geographical structure an organisation or the planned longevity of the allocation, the LIR will be asked to provide additional documentation to justify why a different hierarchy or topology, which consumes less address space, cannot be implemented.  

(3) Segmentation of infrastructure for security 

The final criteria for consideration when evaluating an initial IPv6 allocation is segmentation of the network for specific security requirements.  

For example, an organisation may host a disaster recovery site. Such sites require a completely separate physical infrastructure, with separate addressing requirements, which exactly duplicates the real life operational network.  

Where an LIR requests a larger initial IPv6 allocation based on the segmentation of their infrastructure for security, the RIPE NCC can consider allocating up to one extra bit per network segment. 

What criteria are used when evaluating a subsequent IPv6 allocation?

If an LIR has received an initial allocation and needs more address space (exceeding a /29), there are two options:

1) Achieve sufficient utilisation in the initial allocation

It is important to register the IPv6 deployment in the RIPE Database. Once a sufficient utilisation is documented and confirmed by the RIPE NCC, the LIR qualifies for a subsequent allocation of at least double the initial allocation size. Depending on the initial allocation size, a utilisation of around one third is enough to qualify for a subsequent allocation.

2) Justify new needs

An LIR can justify new needs that have been discovered after the initial allocation was provided. These will be evaluated under the same criteria as initial allocation requests.

The LIR will need to provide an update on their initial addressing plan to identify possible changes. Once we have concluded that the new needs cannot be met with the existing allocation, the LIR will qualify for another one.

Where possible, a subsequent allocation will come from the adjacent address block. This is mandated by RIPE policy to support aggregation. If the allocation exceeds the size of the adjacent block, we will first allocate the adjacent address space and provide a separate address range for the remainder of the request.

To get started with an IPv6 allocation request

An LIR should use the request form in the LIR Portal to request an allocation of IPv6 address space. If the requested prefix is larger than /29, the LIR should provide the following supporting documentation to justify the size:  

  • Addressing/subnetting plan
  • Network topology diagram
  • Size and scope of end sites covered by request
  • Statistics for past network growth (where applicable)
  • Deployment plan (where applicable)

More information

For more information, refer to the RIPE Policy.