I haven't thought about this for several years in depth. So with thanks to both Patrik and Richard for their input.
Speaking as someone at an "end point". I can't use 4.4.e164.arpa given the politics for a very long time. That is pretty universal across E.164.arpa as I understand the situation. Caveat I've not looked for maybe 15 years? But that isn't the complete answer. Even if the E.164 incumbency doesn't want to use ENUM under .arpa it is using enum like deployments to transition to IP only. It is quite clear they view E.164/DIDs as both a moat and trojan horse to persist their business model as they shift to the Internet. In itself that's not the problem. Whether this works or becomes a problem more generally on an IP only network will depend on whether users at the edge are able to assert alternative identifiers between each other as the SS7/ISDN legacy disappears. In that light it is possible that the continuation of E.164.arpa signals something valuable that over the Internet user choice matters and open infrastructures that support choice are seen as important even if users decide to do something else for a period of time. I feel the transition to IP by telcoworld has another 20 years or so to go. Current transition mechanisms may not be sustainable. We don't know that sip trunkers will sustain individual iENUM registers in 5 years even. So having e.164.arpa in the wings which after all took quite some effort to achieve has both latent and potential roles in the coming transitions. ? Christian Hisham Ibrahim <[email protected]> writes: > Dear colleagues, > > I would like to follow up on my previous message regarding ENUM (e164.arpa) > and share a brief update on where things > currently stand. > > As noted earlier, the RIPE NCC has been reviewing the operational status of > the e164.arpa registry in light of its very > limited usage, recent discussion in the RIPE Database Working Group, and the > broader considerations surrounding the > service operated by the RIPE NCC. > > Since my last email, the Internet Architecture Board (IAB) has discussed the > matter at its last meeting. At this stage, the > IAB has indicated that it would like to hear further feedback from the > community before taking any further position. > > ITU-T has also initiated a consultation with Member States on the possible > closure of the ENUM system under > e164.arpa. As mentioned previously, this is an important part of > understanding whether the service is still needed by the > relevant delegating authorities and whether there is a continued operational > justification for maintaining it. > > While the immediate trigger was a limited operational question, the topic > also touches on broader considerations > around community input, governance responsibilities, and coordination with > relevant external bodies such as the IAB, > IANA and ITU-T. > > For the RIPE NCC, the goal remains to approach this carefully and > transparently: to understand whether there is still a > real need for the service, to avoid unnecessary operational or compliance > risk, and to ensure that any future steps are > informed by both community feedback and the views of the appropriate > stakeholders. > > I will present on this topic at RIPE 92, where I will provide more > background, summarise the discussions to date, and > invite further feedback from the RIPE community. > > In the meantime, I encourage anyone with views on this matter to share them > on the RIPE NCC Services Working > Group mailing list so that the discussion can continue openly and with the > benefit of community input. > > Best regards, Hisham Ibrahim Chief Community Officer RIPE NCC > > On Tue, 17 Feb 2026 at 16:13, Hisham Ibrahim <[email protected]> wrote: > > Dear colleagues, > > This message summarises recent discussion regarding ENUM (e164.arpa) and > clarifies the scope and next steps. > > The RIPE NCC has operated the e164.arpa registry for many years under > instructions and coordination > arrangements established with the ITU-T and IAB. These arrangements, and the > operational context for how the > registry is run, are described here: > https://www.ripe.net/manage-ips-and-asns/dns/enum/iab-instructions/ > > Recently, a request was raised in the RIPE Database Working Group to support > ENUM (e164.arpa) in RDAP for > querying the RIPE Database. We noted that RDAP support for ENUM is not > currently implemented, but could be > added if there is clear interest. We also checked current query patterns and > found a few hundred ENUM-related > queries per day in DNS and in Database; so low usage, but not zero. > > Following discussion on the Database WG mailing list, including replies in > support, we proposed implementing RDAP > support for ENUM. While this is a limited operational change, it was > recognised that anything touching E.164 and > e164.arpa can raise political questions that go beyond the purely technical. > > As e164.arpa is directly linked to the ITU E.164 numbering system, the > relevant points of contact are typically > national administrations and the entities they designate. This led us to > consult ITU-T Study Group 2 to clarify the > status of ENUM and its usage and needs for ongoing support. ITU-T will ask > member states for their feedback and > share this with us. > > ITU-T provides an established and coordinated channel to reach those > administrations, and importantly confirm > whether any delegating authorities still rely on the service, so our > technical decisions are informed by real-world > use and help us avoid unnecessary operational risk, confusion, or compliance > headaches (including in the context > of regulatory frameworks such as NIS2). > > We are also reaching out to the IAB regarding these operations, which the > RIPE NCC performs under its instruction > on behalf of the global DNS and Internet community. > > I am sharing this message with the DNS, Database, Cooperation and RIPE NCC > Services Working Group mailing lists > to ensure all relevant working groups are informed. If you wish to share > thoughts in response, please reply to the > thread on the RIPE NCC Services WG mailing list. > > Best regards, > Hisham Ibrahim > Chief Community Officer, > RIPE NCC > > ----- > To unsubscribe from this mailing list or change your subscription > options, please visit: > https://mailman.ripe.net/mailman3/lists/cooperation-wg.ripe.net/ > As we have migrated to Mailman 3, you will need to create an account > with the email matching your subscription before you can change your > settings. > More details at: https://www.ripe.net/membership/mail/mailman-3-migration/ -- Christian de Larrinaga ----- To unsubscribe from this mailing list or change your subscription options, please visit: https://mailman.ripe.net/mailman3/lists/cooperation-wg.ripe.net/ As we have migrated to Mailman 3, you will need to create an account with the email matching your subscription before you can change your settings. More details at: https://www.ripe.net/membership/mail/mailman-3-migration/
