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Revised Operating Instructions for (ENUM)

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Subject: Revised Operating Instructions for (ENUM)
Date: 2 May 2019 at 14:40:40 CEST

Dear colleagues,

The RIPE NCC is the operator of the zone (ENUM) and maintains
the associate registry in accordance with the instructions of the
Internet Architecture Board (IAB). As delegations are based on E.164
country code allocations, any changes to the registry are coordinated
with and approved by the respective holders of the E.164 country code
via the ITU’s Telecommunications Standardisation Bureau (TSB).

Recent checks have shown that over time, many of the current 57
delegations have deteriorated – they are no longer technically
functional or the contacts details for the country code registry have
not been updated.

Seeking advice from the IAB on these matters, they agreed to revise the
instructions to address these issues. Among the changes is new text
regarding the deletion of delegations and instructions that allow the
RIPE NCC to do periodic checks on registry data.

This will allow us to initiate a process to review the existing
delegations and coordinate with the registries, governments and the TSB
to mitigate and correct any errors. In cases where we are unable to
correct an error, we will advise the government involved to remove the
delegation, until such time that a new registry can assume
responsibility for the country code and restore its technical

ITU Study Group 2, which is responsible for the E.164 number registry,
shared our concerns and at its last meeting agreed to update its
instructions to the TSB to reflect these changes. As we remain committed
to coordinating any delegations with TSB, the Member States involved and
Study Group 2, we welcome the study group’s renewed interest in the
topic and its support in reviewing and updating these registrations.

The new instructions have now been published on our website and, with
the IAB’s approval, we will now operate the registry in accordance with

The instructions are available here:

Kind Regards,

Marco Hogewoning
Senior External Relations Officer, RIPE NCC,

Ted Hardie
For the IAB