CLI spoofing has been increasing during the last years with a very negative impact for end-users. ECC Report 338 on CLI spoofing adopted 7th June 2022 contains in the conclusion, under the form of 6 points, possible policy actions to mitigate or stop CLI spoofing. The proposed ECC Recommendation implements conclusion number 4 of the ECC Report 338.

Currently, the very largest share of spoofed calls is caused by inbound calls with national phone numbers over the international gateway. End-users get the impression that they are dealing with reliable parties (e.g. banks of which they are customers) and are thus misled. This recommendation aims to propose measures for such international telephone call traffic so that with a high reliability spoofed telephone calls with national numbers are blocked (or at least the CLI is removed or replaced by a number from a specifically assigned numbering range).

It will draw on the good practices currently applied in several countries and described in ECC Report 338, among others.

Regarding SMS traffic, it is excluded from the recommendation, given its special characteristics, and should be considered in a further ECC Recommendation. The ambition of the recommendation is to move as far as possible towards a common approach in the CEPT countries, particularly from national fixed and mobile E.164 numbers. Also, the question which operator in handling the call should be responsible for the blocking of the call, or the removal or replacement of the CLI, should be addressed in the recommendation.