Draft Policy ARIN-2025-6
Fix Formula in 6.5.2.1c
Status: Under Discussion
Shepherds: William Herrin, Gus Reese
Staff and Legal Review (9 September 2025)
Staff Understanding
NRPM section “6.5.2.1. Size” describes requirements for the size of IPv6 allocations to ISPs/LIRs. Sub-section “c” defines how to calculate the largest allocation justified by the requestor. Accompanying the text description is a mathematical formula that intends to summarize the calculation as “/N where N = P-(X+Y) and P is the organization’s Provider Allocation Unit X is a multiple of 4 greater than 4/3 serving sites and Y is a multiple of 4 greater than 4/3 end sites served by largest serving site.”
This draft policy indicates the formula does not match the text, and intends to correct it with, “This calculation can be summarized as /N where N = P-(X+Y) and P is the organization’s Provider Allocation Unit, X is a multiple of 4 greater than 4/3 log_2(serving sites) and Y is a multiple of 4 greater than 4/3 log_2(end sites served by largest serving site).”
ARIN staff currently implements 6.5.2.1c based on the text alone. The summarized formula is overly complex for your typical IPv6 requestor. The text alone is more easily understood by customers and implemented by ARIN staff. Modifying the formula would have no impact on ARIN operations. Staff would continue to implement 6.5.2.1c based on the text alone. Removing the formula from the NRPM would have no impact on ARIN operations, and would simplify the policy language for IPv6 requestors.
NRPM section “6.5.2.1. Size” includes the text “Provider Allocation Unit”, while sections 2.15 and 2.16 reference the term, “Provider Assignment Unit “. This draft policy intends to update the text in sections 2.15 and 2.16 to “Provider Allocation Unit”. Modifying “Assignment” to “Allocation” aligns with the deprecation of Direct Assignment’s that occurred during ARIN’s fee harmonization. Staff agrees the terms should match between section 2 and section 6. Staff currently considers subnetted Direct Allocations, Reallocations, and Reassignments to be “Provider Assignment Units”. This modification aligns with staff’s current implementation.
Implementable as Written?
Yes
Impact on ARIN Registry Operations and Services
None
Legal Review
No material legal issue
Implementation Timeframe Estimate
3 Months
Implementation Requirements
- Staff Training
- Updates to public documentation