Summary

  • APNIC's hostmasters already spaced IPv6 allocations to leave room for growth. Dean Pemberton and Ren-Hung Hwang wanted the rules of that spacing on a public page.
  • At APNIC 33 in 2012, staff explained the method. Pemberton asked whether publishing it would let him withdraw his proposal and send everyone home half an hour early. The proposal went ahead.
  • The final prop-102 required APNIC to publish its sparse-allocation framework as a numbered document. It was implemented that August; the requirement remains in APNIC's current resource policy.

The half-hour that the meeting did not save

Dean Pemberton heard APNIC staff explain how they laid out IPv6 space and spotted a tempting shortcut. They had a method. They had a slide deck. Why not put the method on the website, retire his policy proposal and give the meeting back thirty minutes? In the APNIC 33 services transcript, his question lands as a joke with a serious invoice attached. The people receiving address blocks could see their own allocation; they could not inspect the operating rule that decided how much empty room surrounded it.

Sparse allocation is a counterintuitive way to share an enormous address pool. Instead of handing out IPv6 blocks in a tight row, the registry leaves gaps. If a network later needs more space, a neighbouring block may let it grow into a larger aggregated prefix rather than announce another distant fragment. APNIC staff described a binary-chop method and separate areas for networks with different growth profiles. Those figures described the registry's 2012 practice, visible in the meeting room. The question Pemberton pressed was who could read and challenge the method after the projector went dark.

His APNIC 33 speaker biography places him in New Zealand ICT architecture and IPv6 task-force work. With Ren-Hung Hwang he wrote prop-102. Their final text said APNIC hostmasters already used sparse allocation, yet its algorithm and parameters had not been publicly documented for member comment. The fix was precise: publish the framework as a numbered APNIC document, with revisions handled through the document editorial process.

A rule leaves the slide deck

The proposal moved quickly. Version 3 was posted on 1 March 2012, the day the Policy SIG reached consensus; the member meeting agreed on 2 March. After the comment period, APNIC's Executive Council endorsed it in May. APNIC records implementation on 20 August. Pemberton got a public rule out of an internal practice, even if nobody got the half-hour back.

The result is still legible in APNIC's current resource policy: section 5.1.2 directs APNIC to document the sparse-allocation framework used to choose IPv6 blocks in numbered document APNIC-114. That sentence matters because the decision about empty space can shape how easily a growing network keeps its routes together. The final proposal bound publication of the method. A future neighbouring allocation remains a decision to be made when need arises; a gap on the map is useful room, not a deed.

Pemberton's small victory was to make a quiet algorithm answerable in public. The registry still places the blocks. Members can now point to a written method when they ask how the placement works. In a world of nearly boundless IPv6 numbers, the valuable commodity was a visible rule for where the empty ones go.

Original records