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Misuse of an E.164 international numbering resource

​According to WTSA Resolution 20 (Rev. Geneva, 2022), “Procedures for allocation and management of international telecommunication numbering, naming, addressing and identification resources”, the assignment of international resources is a responsibility of the Director of TSB. The codes that are allocated by the Director of TSB should be used according to the purposes for which they have been allocated. In addition, WTSA has instructed the Director of TSB, in close collaboration with Study Group 2, and any other relevant study groups, to follow up on the misuse of any numbering, naming, addressing and identification resources and inform the Council accordingly.

The misuse of an E.164 international numbering resource occurs where the use of that numbering resource does not conform to the relevant ITU-T Recommendation(s) assignment criteria for which it was assigned or when an unassigned numbering resource is used in the provision of a telecommunication service. Different types of ITU-T E.164 numbering resources have different assignment criteria, and therefore different forms of misuse may be identified. There are two distinct situations: 
  1. misuse of numbers directly assigned by TSB to entities who meet the assignment criteria established by the relevant ITU-T Recommendations; 
  2. misuse of numbers that are assigned by national authorities (referred to hereafter as numbers indirectly assigned by TSB). The respective procedures are specified in clauses 10 and 11 of Recommendation ITU-T E.156.
An Administration, operating agency (OA), or other assignee that believes misuse of a directly assigned numbering resource is occurring should contact the TSB Director as specified in Recommendation ITU T E.156. The form for submitting such misuse reports can be accessed through the TIES account, at:
https://www.itu.int/net/ITU-T/misuse/secured/Default.aspx

An administration, OA or other assignee that believes misuse of an indirectly assigned international numbering resource is occurring should: 
  1. directly contact the OA believed to be involved in the misuse, if possible. 
  2. contact the administration of the OA that is believed to be involved in the misuse. 
  3. if they are an ITU member, submit a misuse report to TSB using the TSB website. The misuse report submitted to TSB will be sent to the mailing list created for this purpose, so that originating networks are aware and can take actions to avoid routing calls to the numbers that are being misused.

In providing information regarding possible misuse, members are asked to explain why they believe that a misuse is occurring, for example use of non-assigned resources, or incorrect routing of assigned resources, or use of resources for purposes other than those for which they were assigned.
In order to implement the provisions of this Recommendation, TSB has created a new mailing list that is open only to ITU members:
  • Subscribe to the mailing list here.
  • Mailing list archive is here​.
All reports of misuse of indirectly assigned international numbering resources that are reported to TSB will be posted to that mailing list. Note that the misusereports@lists.itu.int mailing list will only distribute messages sent from TSB. A separate mailing list, t22sg2misuse@lists.itu.int, is available for discussion among members (subscribe here; archive here).

Furthermore, TSB has is hereby requesting that Administrations and OAs that are members of ITU, and assignees, notify to TSB the Numbering focal point for their organization. The information will be published on the ITU website: https://www.itu.int/en/ITU-T/inr/misuse/P​​ages/​focal-points.aspx, unless confidentiality is requested, in which case the contact details will be retained within TSB. Kindly designate the Numbering focal point for your organization, providing the following information to numbering@itu.int:
  • First name, family name, e-mail address and/or ITU account username. Alternatively, a dedicated email address for numbering misuse may be provided instead of a personal email address.
  • Country and organization.
  • Whether or not you wish these contact details to be visible publicly via the ITU website.
If no specific information is provided, or if no contact can be made with the Numbering focal point, then questions relating to misuse reports will be addressed to the main ADMIN contact for your organization, as indicated in the Global Directory.

Further details can be found in TSB Circular 81 (March 2023), "Implementation of Recommendation ITU-T E.156 on Guidelines for ITU-T action on reported misuse of ITU-T E.164 number resources".


Member States are also invited to publish in the ITU Operational Bulletin such communications as they think appropriate in connection with possible misuse of numbering resources that is their responsibility, for example, pointing out that particular numbering ranges are not assigned and therefore should not be routed.
It should be noted that TSB will not intervene in any disputes concerning numbering resources assigned to Member States.

The attention of Member States is drawn to Council Resolution 262, Complaints from Members of the Union against other Members of the Union, which invites Members of the Union to abstain from calling upon the Secretary General to acquaint other Members with their disputes, either by publication in a Notification or by any other means; and instructs the Secretary General to refer those Members submitting complaints against other Members to the terms of the present Resolution, and to advise them that, in consequence, he cannot comply with their request. This is a generic resolution that also applies to the Director of TSB and to notices for the ITU Operational Bulletin.