Summary

  • In 2013 Mark Elkins told an AFRINIC policy meeting that an anycast service might need about four addresses yet fail the ordinary utilization test for an allocation or assignment.
  • The later policy allowed an anycast /24, an IPv6 /48 and an ASN where requested, waived the usual initial utilization threshold and marked the resources for anycast use. AFRINIC reported the expansion implemented in April 2015.

Imagine explaining to a registry that four addresses are enough to run your service and still too few to qualify for the network you need. That was the paperwork trap around anycast. Several sites can serve the same destination address; the network needs a prefix operators will actually route. Counting occupied addresses inside that prefix misses the point. At AFRINIC's 2013 policy meeting, Mark Elkins, presenting as a coauthor, put the problem in plain numbers: about four IP addresses might do the work, while the ordinary minimum-use justification could reject the request. AFRINIC staff said they had already turned down several such applications.

The early proposal sought a specific IPv4 path. The meeting agreed to send it to last call, but participants also asked why IPv6 was absent and why the rule should single out web, authoritative DNS or GRX services. A policy that tries to name every useful network service can grow old faster than a router. Elkins returned with an expansion. AFRINIC's 2014 proposal record offers one /24 of IPv4, one /48 of IPv6 and an ASN for anycast purposes if requested. It treats those blocks as fully utilized when a holder seeks more resources, waives ordinary initial utilization tests for anycast requests, bars further assignment or suballocation, and gives the blocks an ASSIGNED ANYCAST registry label.

That design did more than hand out a convenient prefix. It moved the test from how many addresses light up to what the block is for and how it is recorded. At AFRINIC-21, speakers pressed for a broader service definition and adjusted the wording around an ASN from a mandatory-sounding “and” to an optional “or.” The meeting found consensus for last call with those changes. The next meeting's implementation report says the IPv6 and ASN extension was implemented in April 2015. AFRINIC's resource-status guide still lists ASSIGNED ANYCAST for IPv4, IPv6 and ASNs. Four busy addresses had finally escaped a test built for filling rows.