[ARIN-consult] Consultation on the Future of ARIN’s Directory Services

Fri Aug 14 15:41:17 EDT 2026

+1 to this

As far as I can tell, the proposed port 43 WHOIS retirement is driven
by two main goals:

1. Reducing the cost ARIN has to pay to maintain legacy services
2. Encouraging people to adopt RDAP and stop using port 43 WHOIS in
production services by breaking their workflows

Retiring port 43 is certainly one way to accomplish that, but I think
there is a way to accomplish those goals without doing so.

- Create a lightweight service that mimics the WHOIS registry by
translating the lookups to RDAP behind the scenes and reformatting the
output.
- Use this new service to replace the (presumably costly)
infrastructure used to run the existing WHOIS services.
- Heavily ratelimit that service such that it is only useful for low-
volume users (e.g., individuals).

On a personal note, port 43 WHOIS is an adorable and historically
important protocol that holds a special place in the hearts of many. I
would hate to see it go away completely.

Regarding distributions not shipping RDAP clients, I suspect that might
change once ICANN-RDAP reaches its 1.0.0 release. (It even supports
WHOIS-style formatting!)

Best,
Bradan Fleming

On Fri, 2026-08-14 at 13:21 -0500, Mark Van Daele via ARIN-consult
wrote:
> ARIN team/Community,
> 
> Thank you for the opportunity to provide input on the proposed 
> retirement timelines for Whois‑RWS, RWhois, and Whois Port 43. I 
> appreciate ARIN’s continued efforts to modernize directory services and 
> align with IETF standards.
> 
> After reviewing the consultation request, I support the retirement of 
> Whois‑RWS and RWhois. Both services are legacy mechanisms with limited 
> adoption, redundant functionality, and meaningful operational overhead. 
> Their planned deprecation makes sense especially given low usage, and 
> the transition to RDAP for these two protocols is appropriate and 
> beneficial.
> 
> However, I strongly recommend retaining support for Whois Port 43 going 
> forward. While RDAP is unquestionably the modern standard, Port 43 
> continues to serve a large and diverse operational community including:
> 
> * Users of operating system distributions that still ship Port 43 
> clients by default
> * Legacy automation and tooling across countless organizations
> * Security operations centers
> * Threat intelligence platforms
> * Academic researchers
> * Law enforcement
> 
> The volume and breadth of Whois Port 43 usage is significantly higher 
> than any other legacy protocol. Its simplicity, ubiquity, and 
> compatibility with decades of tooling make it uniquely valuable. Even 
> with RDAP available, Port 43 remains deeply embedded in workflows that 
> cannot be easily or quickly replaced.
> 
> For these reasons, I believe Whois Port 43 should continue to coexist 
> with RDAP rather than be fully retired. Maintaining Port 43 alongside 
> RDAP would preserve critical operational continuity for the broader 
> Internet community while still allowing ARIN to advance RDAP as the 
> preferred and modernized interface.
> 
> Thank you for considering this perspective, I appreciate ARIN’s 
> engagement with the community before making major changes.
> 
> Thank You,
> Mark Van Daele
> 
> On 8/14/2026 10:16 AM, ARIN wrote:
> > ARIN is seeking feedback from the community on a proposed road map to streamline and consolidate its directory services.
> > 
> > ARIN currently maintains four directory information protocols: Whois-RWS, RWhois, Whois (Port 43), and RDAP. Supporting multiple redundant services that provide the same information creates additional administrative and operational overhead to the organization. To reduce ARIN’s attack surface, streamline operations and lower future operational overhead, ARIN proposes retiring use of older protocols in favor of RDAP as our single, standardized directory service.
> > 
> > This transition is an important step toward improving alignment with established IETF standards.
> > 
> > We have already seen this transition in the domain industry with ICANN mandating the use of RDAP for directory services and dropping the requirement to support Whois. We also expect RDAP clients to become increasingly common in OS distributions in the coming years.
> > 
> > ------
> > Benefits of Transition to RDAP 
> > 
> > - Enhanced Directory Services: Future enhancements, such as geolocation, will only be implemented in RDAP. 
> > - Standardization and Automation: RDAP’s standardized data structure will improve automation for clients and provide greater flexibility in managing future data changes. 
> > - Reduced Technical Overhead: Removing old and redundant services will provide time and cost savings for ARIN. 
> > 
> > ------
> > Timeline and Retirement Planning
> > 
> > This consultation seeks community input for the proposed retirement timelines below. We are keenly interested in receiving specific input on any barriers and/or obstacles these changes may create for customers, as well as steps ARIN can take to ensure a smooth transition. Note that the retirement plans for each impacted directory service will be completed independently, though in some cases work may be conducted concurrently.
> > 
> > ***
> > Whois-RWS Retirement Plan and Timeline
> > 
> > ARIN currently offers Whois-RWS in two formats: an API and a web interface (located at https://whois.arin.net/ui/). Because the API has the same functionality between Whois-RWS and RDAP, ARIN proposes sunsetting the Whois-RWS API following a 180-day customer outreach program. This will include updating the Whois-RWS payloads to include a notification to users, as well as a robust communication strategy that includes announcements, social promotion, and other outreach.
> > 
> > The Whois-RWS web interface will remain available until work is completed to ensure parity, providing equivalent query capabilities to RDAP. The changeover from Whois-RWS to RDAP will be transparent to end users visiting that URL. ARIN will inform the community a minimum of 30 days before the retirement of the Whois-RWS web interface, noting the switch to RDAP will not change the end user experience.
> > 
> > ***
> > RWhois Retirement Plan and Timeline
> > 
> > When RWhois server use is retired, we will provide organizations with a recommendation for an open-source RDAP server implementation. To help ease the transition and migration of data, ARIN plans to provide a conversion tool for populating that recommended RDAP server with existing RWhois data. When the tool is publicly available, ARIN proposes a 365-day sunsetting timeline for RWhois. This will allow for robust communication and direct outreach to organizations who use RWhois and plan to either convert to the RDAP client or discontinue their use of local clients and report their reassignment information directly to ARIN instead.
> > 
> > ***
> > Whois (Port 43) Retirement Plan and Timeline
> > 
> > ARIN understands that Whois (Port 43) carries a high volume of queries and will require the longest timeline to retire. We propose a two-year sunsetting window, during which ARIN will engage in active outreach to users. This will include updates to Whois (Port 43) results during the sunsetting period that will contain information about the retirement deadline.
> > 
> > Because Whois (Port 43) has been the historically preferred method of querying Internet number resource registration data, it remains heavily used by cybersecurity professionals, researchers, law enforcement, and many other types of organizations. ARIN will seek to engage beyond our community to raise awareness of the planned retirement date for Whois (Port 43).
> > 
> > ------
> > After the retirement of the directory service protocols described above and listed below, ARIN will only support RDAP as our single, standardized directory service.
> > 
> > - Whois-RWS: on or after 1 July 2027
> > - RWhois: dependent on migration tool release date, but no sooner than 1 January 2028
> > - Whois (Port 43): on or after 1 January 2029
> > 
> > Throughout the sunsetting process for all services, ARIN will engage with our community to ensure customers and users are well-informed about the retirement of the described services and ARIN’s transition to RDAP as its standard directory service.
> > 
> > We look forward to your feedback on the proposed timelines for retirement for Whois-RWS, RWhois, and Whois (Port 43). We ask that you consider each service independently, with the understanding that each of these services may impact your organization differently.
> > 
> > Please provide comments to arin-consult at arin.net. You can subscribe to this mailing list at https://lists.arin.net/mailman/listinfo/arin-consult.
> > 
> > This consultation will remain open until 5:00 PM ET on 14 September 2026. ARIN seeks clear direction through community input, so your feedback is important.
> > 
> > Thank you for your continued support in improving ARIN’s services.
> > 
> > Regards,
> > 
> > John Curran
> > President and CEO
> > ARIN
> > 
> > ------
> > Relevant links:
> > - Presentation from ARIN 56: https://www.arin.net/participate/meetings/ARIN56/materials/arin56_directoryservices.pdf
> > - IETF Standard for RDAP: https://www.rfc-editor.org/info/std95
> > - Guide to RDAP Client Implementations: https://rdap.rcode3.com/client_implementations/index.html
> > - ARIN RDAP Documentation: https://www.arin.net/resources/registry/whois/rdap/
> > 
> > 
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