Summary

  • On 14 August, ARIN opened a consultation on moving its directory services toward RDAP alone. It currently maintains Whois-RWS, RWhois, Whois on port 43 and RDAP; the consultation says that overlap creates administrative and operational overhead.
  • The consultation closes at 5:00 PM Eastern Time on 14 September 2026. ARIN describes possible staged retirements, not a completed protocol withdrawal: its earliest listed dates are 1 July 2027 for Whois-RWS, 1 January 2028 for RWhois and 1 January 2029 for port 43 Whois.

What is being consulted on

The issue is a directory-service operating model, not a change to Internet number registration itself. ARIN says it wants to consolidate services around Registration Data Access Protocol (RDAP), citing a smaller attack surface, lower future technical overhead and closer alignment with IETF standards. The announcement also points to structured responses and automation as practical reasons for a common protocol.

The four services do not have the same proposed path. For Whois-RWS, ARIN proposes outreach followed by a 180-day sunset period, while keeping the web interface until RDAP has functional parity; it says a 30-day notice and a transparent URL switch are contemplated. For RWhois, it proposes an open-source RDAP server and conversion tool before a 365-day retirement period. For port 43 Whois, the proposed horizon is two years because ARIN describes the service as high-volume and used by a broad group that includes researchers and law-enforcement users.

The operational distinction

The announcement is a consultation, not evidence that one of those interfaces has already disappeared. Its dates are lower bounds, and the RWhois track is expressly conditional on an RDAP server and conversion tool. Users who depend on a particular endpoint therefore have a concrete task: identify the calling application, the data fields it relies on and whether its parsing logic already accepts RDAP responses. A public service label is not enough; dependencies often sit inside monitoring, abuse handling, asset inventory or incident-response workflows.

ARIN says the retirements could occur independently or at the same time. That preserves a useful uncertainty: the published text does not establish a final sequence, an implementation date, a compatibility result, or a decision after consultation. It also does not say that every existing consumer will migrate without changes.

Sources